ctdb-takeover: Send tcp tickles immediately on STARTUP control
[samba.git] / ctdb / server / ctdb_takeover.c
index 46a08c81e83f2db41305ff6181de5ca54d9809a3..cd240875ba2e4cc48424de59b2fe5e93f9855bb6 100644 (file)
@@ -30,6 +30,7 @@
 #include "lib/util/dlinklist.h"
 #include "lib/util/debug.h"
 #include "lib/util/samba_util.h"
+#include "lib/util/sys_rw.h"
 #include "lib/util/util_process.h"
 
 #include "ctdb_private.h"
@@ -55,51 +56,100 @@ struct ctdb_interface {
        uint32_t references;
 };
 
-static const char *ctdb_vnn_iface_string(const struct ctdb_vnn *vnn)
+struct vnn_interface {
+       struct vnn_interface *prev, *next;
+       struct ctdb_interface *iface;
+};
+
+/* state associated with a public ip address */
+struct ctdb_vnn {
+       struct ctdb_vnn *prev, *next;
+
+       struct ctdb_interface *iface;
+       struct vnn_interface *ifaces;
+       ctdb_sock_addr public_address;
+       uint8_t public_netmask_bits;
+
+       /* the node number that is serving this public address, if any.
+          If no node serves this ip it is set to -1 */
+       int32_t pnn;
+
+       /* List of clients to tickle for this public address */
+       struct ctdb_tcp_array *tcp_array;
+
+       /* whether we need to update the other nodes with changes to our list
+          of connected clients */
+       bool tcp_update_needed;
+
+       /* a context to hang sending gratious arp events off */
+       TALLOC_CTX *takeover_ctx;
+
+       /* Set to true any time an update to this VNN is in flight.
+          This helps to avoid races. */
+       bool update_in_flight;
+
+       /* If CTDB_CONTROL_DEL_PUBLIC_IP is received for this IP
+        * address then this flag is set.  It will be deleted in the
+        * release IP callback. */
+       bool delete_pending;
+};
+
+static const char *iface_string(const struct ctdb_interface *iface)
 {
-       if (vnn->iface) {
-               return vnn->iface->name;
-       }
+       return (iface != NULL ? iface->name : "__none__");
+}
 
-       return "__none__";
+static const char *ctdb_vnn_iface_string(const struct ctdb_vnn *vnn)
+{
+       return iface_string(vnn->iface);
 }
 
-static int ctdb_add_local_iface(struct ctdb_context *ctdb, const char *iface)
+static struct ctdb_interface *ctdb_find_iface(struct ctdb_context *ctdb,
+                                             const char *iface);
+
+static struct ctdb_interface *
+ctdb_add_local_iface(struct ctdb_context *ctdb, const char *iface)
 {
        struct ctdb_interface *i;
 
        if (strlen(iface) > CTDB_IFACE_SIZE) {
                DEBUG(DEBUG_ERR, ("Interface name too long \"%s\"\n", iface));
-               return -1;
+               return NULL;
        }
 
        /* Verify that we don't have an entry for this ip yet */
-       for (i=ctdb->ifaces;i;i=i->next) {
-               if (strcmp(i->name, iface) == 0) {
-                       return 0;
-               }
+       i = ctdb_find_iface(ctdb, iface);
+       if (i != NULL) {
+               return i;
        }
 
        /* create a new structure for this interface */
        i = talloc_zero(ctdb, struct ctdb_interface);
-       CTDB_NO_MEMORY_FATAL(ctdb, i);
+       if (i == NULL) {
+               DEBUG(DEBUG_ERR, (__location__ " out of memory\n"));
+               return NULL;
+       }
        i->name = talloc_strdup(i, iface);
-       CTDB_NO_MEMORY(ctdb, i->name);
+       if (i->name == NULL) {
+               DEBUG(DEBUG_ERR, (__location__ " out of memory\n"));
+               talloc_free(i);
+               return NULL;
+       }
 
        i->link_up = true;
 
        DLIST_ADD(ctdb->ifaces, i);
 
-       return 0;
+       return i;
 }
 
-static bool vnn_has_interface_with_name(struct ctdb_vnn *vnn,
-                                       const char *name)
+static bool vnn_has_interface(struct ctdb_vnn *vnn,
+                             const struct ctdb_interface *iface)
 {
-       int n;
+       struct vnn_interface *i;
 
-       for (n = 0; vnn->ifaces[n] != NULL; n++) {
-               if (strcmp(name, vnn->ifaces[n]) == 0) {
+       for (i = vnn->ifaces; i != NULL; i = i->next) {
+               if (iface == i->iface) {
                        return true;
                }
        }
@@ -130,14 +180,14 @@ static void ctdb_remove_orphaned_ifaces(struct ctdb_context *ctdb,
                next = i->next;
 
                /* Only consider interfaces named in the given VNN. */
-               if (!vnn_has_interface_with_name(vnn, i->name)) {
+               if (!vnn_has_interface(vnn, i)) {
                        continue;
                }
 
                /* Search for a vnn with this interface. */
                found = false;
                for (tv=ctdb->vnn; tv; tv=tv->next) {
-                       if (vnn_has_interface_with_name(tv, i->name)) {
+                       if (vnn_has_interface(tv, i)) {
                                found = true;
                                break;
                        }
@@ -169,16 +219,13 @@ static struct ctdb_interface *ctdb_find_iface(struct ctdb_context *ctdb,
 static struct ctdb_interface *ctdb_vnn_best_iface(struct ctdb_context *ctdb,
                                                  struct ctdb_vnn *vnn)
 {
-       int i;
+       struct vnn_interface *i;
        struct ctdb_interface *cur = NULL;
        struct ctdb_interface *best = NULL;
 
-       for (i=0; vnn->ifaces[i]; i++) {
+       for (i = vnn->ifaces; i != NULL; i = i->next) {
 
-               cur = ctdb_find_iface(ctdb, vnn->ifaces[i]);
-               if (cur == NULL) {
-                       continue;
-               }
+               cur = i->iface;
 
                if (!cur->link_up) {
                        continue;
@@ -251,7 +298,7 @@ static void ctdb_vnn_unassign_iface(struct ctdb_context *ctdb,
 static bool ctdb_vnn_available(struct ctdb_context *ctdb,
                               struct ctdb_vnn *vnn)
 {
-       int i;
+       struct vnn_interface *i;
 
        /* Nodes that are not RUNNING can not host IPs */
        if (ctdb->runstate != CTDB_RUNSTATE_RUNNING) {
@@ -266,15 +313,8 @@ static bool ctdb_vnn_available(struct ctdb_context *ctdb,
                return true;
        }
 
-       for (i=0; vnn->ifaces[i]; i++) {
-               struct ctdb_interface *cur;
-
-               cur = ctdb_find_iface(ctdb, vnn->ifaces[i]);
-               if (cur == NULL) {
-                       continue;
-               }
-
-               if (cur->link_up) {
+       for (i = vnn->ifaces; i != NULL; i = i->next) {
+               if (i->iface->link_up) {
                        return true;
                }
        }
@@ -400,12 +440,6 @@ static int32_t ctdb_announce_vnn_iface(struct ctdb_context *ctdb,
        return 0;
 }
 
-struct takeover_callback_state {
-       struct ctdb_req_control_old *c;
-       ctdb_sock_addr *addr;
-       struct ctdb_vnn *vnn;
-};
-
 struct ctdb_do_takeip_state {
        struct ctdb_req_control_old *c;
        struct ctdb_vnn *vnn;
@@ -423,8 +457,6 @@ static void ctdb_do_takeip_callback(struct ctdb_context *ctdb, int status,
        TDB_DATA data;
 
        if (status != 0) {
-               struct ctdb_node *node = ctdb->nodes[ctdb->pnn];
-       
                if (status == -ETIME) {
                        ctdb_ban_self(ctdb);
                }
@@ -433,7 +465,6 @@ static void ctdb_do_takeip_callback(struct ctdb_context *ctdb, int status,
                                 ctdb_vnn_iface_string(state->vnn)));
                ctdb_request_control_reply(ctdb, state->c, NULL, status, NULL);
 
-               node->flags |= NODE_FLAGS_UNHEALTHY;
                talloc_free(state);
                return;
        }
@@ -498,7 +529,7 @@ static int32_t ctdb_do_takeip(struct ctdb_context *ctdb,
        state = talloc(vnn, struct ctdb_do_takeip_state);
        CTDB_NO_MEMORY(ctdb, state);
 
-       state->c = talloc_steal(ctdb, c);
+       state->c = NULL;
        state->vnn   = vnn;
 
        vnn->update_in_flight = true;
@@ -527,6 +558,7 @@ static int32_t ctdb_do_takeip(struct ctdb_context *ctdb,
                return -1;
        }
 
+       state->c = talloc_steal(ctdb, c);
        return 0;
 }
 
@@ -544,16 +576,16 @@ static void ctdb_do_updateip_callback(struct ctdb_context *ctdb, int status,
 {
        struct ctdb_do_updateip_state *state =
                talloc_get_type(private_data, struct ctdb_do_updateip_state);
-       int32_t ret;
 
        if (status != 0) {
                if (status == -ETIME) {
                        ctdb_ban_self(ctdb);
                }
-               DEBUG(DEBUG_ERR,(__location__ " Failed to move IP %s from interface %s to %s\n",
-                       ctdb_addr_to_str(&state->vnn->public_address),
-                       state->old->name,
-                       ctdb_vnn_iface_string(state->vnn)));
+               DEBUG(DEBUG_ERR,
+                     ("Failed update of IP %s from interface %s to %s\n",
+                      ctdb_addr_to_str(&state->vnn->public_address),
+                      iface_string(state->old),
+                      ctdb_vnn_iface_string(state->vnn)));
 
                /*
                 * All we can do is reset the old interface
@@ -568,17 +600,6 @@ static void ctdb_do_updateip_callback(struct ctdb_context *ctdb, int status,
                return;
        }
 
-       if (ctdb->do_checkpublicip) {
-
-       ret = ctdb_announce_vnn_iface(ctdb, state->vnn);
-       if (ret != 0) {
-               ctdb_request_control_reply(ctdb, state->c, NULL, -1, NULL);
-               talloc_free(state);
-               return;
-       }
-
-       }
-
        /* the control succeeded */
        ctdb_request_control_reply(ctdb, state->c, NULL, 0, NULL);
        talloc_free(state);
@@ -601,6 +622,7 @@ static int32_t ctdb_do_updateip(struct ctdb_context *ctdb,
        int ret;
        struct ctdb_do_updateip_state *state;
        struct ctdb_interface *old = vnn->iface;
+       const char *old_name = iface_string(old);
        const char *new_name;
 
        if (vnn->update_in_flight) {
@@ -614,16 +636,15 @@ static int32_t ctdb_do_updateip(struct ctdb_context *ctdb,
        ctdb_vnn_unassign_iface(ctdb, vnn);
        ret = ctdb_vnn_assign_iface(ctdb, vnn);
        if (ret != 0) {
-               DEBUG(DEBUG_ERR,("update of IP %s/%u failed to "
-                                "assin a usable interface (old iface '%s')\n",
+               DEBUG(DEBUG_ERR,("Update of IP %s/%u failed to "
+                                "assign a usable interface (old iface '%s')\n",
                                 ctdb_addr_to_str(&vnn->public_address),
                                 vnn->public_netmask_bits,
-                                old->name));
+                                old_name));
                return -1;
        }
 
-       new_name = ctdb_vnn_iface_string(vnn);
-       if (old->name != NULL && new_name != NULL && !strcmp(old->name, new_name)) {
+       if (old == vnn->iface) {
                /* A benign update from one interface onto itself.
                 * no need to run the eventscripts in this case, just return
                 * success.
@@ -635,18 +656,19 @@ static int32_t ctdb_do_updateip(struct ctdb_context *ctdb,
        state = talloc(vnn, struct ctdb_do_updateip_state);
        CTDB_NO_MEMORY(ctdb, state);
 
-       state->c = talloc_steal(ctdb, c);
+       state->c = NULL;
        state->old = old;
        state->vnn = vnn;
 
        vnn->update_in_flight = true;
        talloc_set_destructor(state, ctdb_updateip_destructor);
 
+       new_name = ctdb_vnn_iface_string(vnn);
        DEBUG(DEBUG_NOTICE,("Update of IP %s/%u from "
                            "interface %s to %s\n",
                            ctdb_addr_to_str(&vnn->public_address),
                            vnn->public_netmask_bits,
-                           old->name,
+                           old_name,
                            new_name));
 
        ret = ctdb_event_script_callback(ctdb,
@@ -655,18 +677,20 @@ static int32_t ctdb_do_updateip(struct ctdb_context *ctdb,
                                         state,
                                         CTDB_EVENT_UPDATE_IP,
                                         "%s %s %s %u",
-                                        state->old->name,
+                                        old_name,
                                         new_name,
                                         ctdb_addr_to_str(&vnn->public_address),
                                         vnn->public_netmask_bits);
        if (ret != 0) {
-               DEBUG(DEBUG_ERR,(__location__ " Failed update IP %s from interface %s to %s\n",
-                                ctdb_addr_to_str(&vnn->public_address),
-                                old->name, new_name));
+               DEBUG(DEBUG_ERR,
+                     ("Failed update IP %s from interface %s to %s\n",
+                      ctdb_addr_to_str(&vnn->public_address),
+                      old_name, new_name));
                talloc_free(state);
                return -1;
        }
 
+       state->c = talloc_steal(ctdb, c);
        return 0;
 }
 
@@ -733,19 +757,6 @@ int32_t ctdb_control_takeover_ip(struct ctdb_context *ctdb,
                return -1;
        }
 
-       if (vnn->iface == NULL && vnn->pnn == -1 && have_ip && best_iface != NULL) {
-               DEBUG(DEBUG_ERR,("Taking over newly created ip\n"));
-               have_ip = false;
-       }
-
-
-       if (vnn->iface == NULL && have_ip) {
-               DEBUG(DEBUG_CRIT,(__location__ " takeoverip of IP %s is known to the kernel, "
-                                 "but we have no interface assigned, has someone manually configured it? Ignore for now.\n",
-                                ctdb_addr_to_str(&vnn->public_address)));
-               return 0;
-       }
-
        if (vnn->pnn != ctdb->pnn && have_ip && vnn->pnn != -1) {
                DEBUG(DEBUG_CRIT,(__location__ " takeoverip of IP %s is known to the kernel, "
                                  "and we have it on iface[%s], but it was assigned to node %d"
@@ -757,12 +768,16 @@ int32_t ctdb_control_takeover_ip(struct ctdb_context *ctdb,
        }
 
        if (vnn->pnn == -1 && have_ip) {
-               vnn->pnn = ctdb->pnn;
-               DEBUG(DEBUG_CRIT,(__location__ " takeoverip of IP %s is known to the kernel, "
-                                 "and we already have it on iface[%s], update local daemon\n",
-                                ctdb_addr_to_str(&vnn->public_address),
-                                 ctdb_vnn_iface_string(vnn)));
-               return 0;
+               /* This will cause connections to be reset and
+                * reestablished.  However, this is a very unusual
+                * situation and doing this will completely repair the
+                * inconsistency in the VNN.
+                */
+               DEBUG(DEBUG_WARNING,
+                     (__location__
+                      " Doing updateip for IP %s already on an interface\n",
+                      ctdb_addr_to_str(&vnn->public_address)));
+               do_updateip = true;
        }
 
        if (vnn->iface) {
@@ -820,15 +835,47 @@ static void do_delete_ip(struct ctdb_context *ctdb, struct ctdb_vnn *vnn)
        talloc_free(vnn);
 }
 
+static struct ctdb_vnn *release_ip_post(struct ctdb_context *ctdb,
+                                       struct ctdb_vnn *vnn,
+                                       ctdb_sock_addr *addr)
+{
+       TDB_DATA data;
+
+       /* Send a message to all clients of this node telling them
+        * that the cluster has been reconfigured and they should
+        * close any connections on this IP address
+        */
+       data.dptr = (uint8_t *)ctdb_addr_to_str(addr);
+       data.dsize = strlen((char *)data.dptr)+1;
+       DEBUG(DEBUG_INFO, ("Sending RELEASE_IP message for %s\n", data.dptr));
+       ctdb_daemon_send_message(ctdb, ctdb->pnn, CTDB_SRVID_RELEASE_IP, data);
+
+       ctdb_vnn_unassign_iface(ctdb, vnn);
+
+       /* Process the IP if it has been marked for deletion */
+       if (vnn->delete_pending) {
+               do_delete_ip(ctdb, vnn);
+               return NULL;
+       }
+
+       return vnn;
+}
+
+struct release_ip_callback_state {
+       struct ctdb_req_control_old *c;
+       ctdb_sock_addr *addr;
+       struct ctdb_vnn *vnn;
+       uint32_t target_pnn;
+};
+
 /*
   called when releaseip event finishes
  */
-static void release_ip_callback(struct ctdb_context *ctdb, int status, 
+static void release_ip_callback(struct ctdb_context *ctdb, int status,
                                void *private_data)
 {
-       struct takeover_callback_state *state = 
-               talloc_get_type(private_data, struct takeover_callback_state);
-       TDB_DATA data;
+       struct release_ip_callback_state *state =
+               talloc_get_type(private_data, struct release_ip_callback_state);
 
        if (status == -ETIME) {
                ctdb_ban_self(ctdb);
@@ -846,31 +893,15 @@ static void release_ip_callback(struct ctdb_context *ctdb, int status,
                }
        }
 
-       /* send a message to all clients of this node telling them
-          that the cluster has been reconfigured and they should
-          release any sockets on this IP */
-       data.dptr = (uint8_t *)talloc_strdup(state, ctdb_addr_to_str(state->addr));
-       CTDB_NO_MEMORY_VOID(ctdb, data.dptr);
-       data.dsize = strlen((char *)data.dptr)+1;
-
-       DEBUG(DEBUG_INFO,(__location__ " sending RELEASE_IP for '%s'\n", data.dptr));
-
-       ctdb_daemon_send_message(ctdb, ctdb->pnn, CTDB_SRVID_RELEASE_IP, data);
-
-       ctdb_vnn_unassign_iface(ctdb, state->vnn);
-
-       /* Process the IP if it has been marked for deletion */
-       if (state->vnn->delete_pending) {
-               do_delete_ip(ctdb, state->vnn);
-               state->vnn = NULL;
-       }
+       state->vnn->pnn = state->target_pnn;
+       state->vnn = release_ip_post(ctdb, state->vnn, state->addr);
 
        /* the control succeeded */
        ctdb_request_control_reply(ctdb, state->c, NULL, 0, NULL);
        talloc_free(state);
 }
 
-static int ctdb_releaseip_destructor(struct takeover_callback_state *state)
+static int ctdb_releaseip_destructor(struct release_ip_callback_state *state)
 {
        if (state->vnn != NULL) {
                state->vnn->update_in_flight = false;
@@ -887,10 +918,10 @@ int32_t ctdb_control_release_ip(struct ctdb_context *ctdb,
                                bool *async_reply)
 {
        int ret;
-       struct takeover_callback_state *state;
+       struct release_ip_callback_state *state;
        struct ctdb_public_ip *pip = (struct ctdb_public_ip *)indata.dptr;
        struct ctdb_vnn *vnn;
-       char *iface;
+       const char *iface;
 
        /* update our vnn list */
        vnn = find_public_ip_vnn(ctdb, &pip->addr);
@@ -899,16 +930,20 @@ int32_t ctdb_control_release_ip(struct ctdb_context *ctdb,
                        ctdb_addr_to_str(&pip->addr)));
                return 0;
        }
-       vnn->pnn = pip->pnn;
 
        /* stop any previous arps */
        talloc_free(vnn->takeover_ctx);
        vnn->takeover_ctx = NULL;
 
-       /* Some ctdb tool commands (e.g. moveip) send
-        * lazy multicast to drop an IP from any node that isn't the
-        * intended new node.  The following causes makes ctdbd ignore
-        * a release for any address it doesn't host.
+       /* RELEASE_IP controls are sent to all nodes that should not
+        * be hosting a particular IP.  This serves 2 purposes.  The
+        * first is to help resolve any inconsistencies.  If a node
+        * does unexpectly host an IP then it will be released.  The
+        * 2nd is to use a "redundant release" to tell non-takeover
+        * nodes where an IP is moving to.  This is how "ctdb ip" can
+        * report the (likely) location of an IP by only asking the
+        * local node.  Redundant releases need to update the PNN but
+        * are otherwise ignored.
         */
        if (ctdb->tunable.disable_ip_failover == 0 && ctdb->do_checkpublicip) {
                if (!ctdb_sys_have_ip(&pip->addr)) {
@@ -916,6 +951,7 @@ int32_t ctdb_control_release_ip(struct ctdb_context *ctdb,
                                ctdb_addr_to_str(&pip->addr),
                                vnn->public_netmask_bits,
                                ctdb_vnn_iface_string(vnn)));
+                       vnn->pnn = pip->pnn;
                        ctdb_vnn_unassign_iface(ctdb, vnn);
                        return 0;
                }
@@ -924,6 +960,7 @@ int32_t ctdb_control_release_ip(struct ctdb_context *ctdb,
                        DEBUG(DEBUG_DEBUG,("Redundant release of IP %s/%u (ip not held)\n",
                                           ctdb_addr_to_str(&pip->addr),
                                           vnn->public_netmask_bits));
+                       vnn->pnn = pip->pnn;
                        return 0;
                }
        }
@@ -941,7 +978,7 @@ int32_t ctdb_control_release_ip(struct ctdb_context *ctdb,
                return -1;
        }
 
-       iface = strdup(ctdb_vnn_iface_string(vnn));
+       iface = ctdb_vnn_iface_string(vnn);
 
        DEBUG(DEBUG_NOTICE,("Release of IP %s/%u on interface %s  node:%d\n",
                ctdb_addr_to_str(&pip->addr),
@@ -949,24 +986,23 @@ int32_t ctdb_control_release_ip(struct ctdb_context *ctdb,
                iface,
                pip->pnn));
 
-       state = talloc(ctdb, struct takeover_callback_state);
+       state = talloc(ctdb, struct release_ip_callback_state);
        if (state == NULL) {
                ctdb_set_error(ctdb, "Out of memory at %s:%d",
                               __FILE__, __LINE__);
-               free(iface);
                return -1;
        }
 
-       state->c = talloc_steal(state, c);
-       state->addr = talloc(state, ctdb_sock_addr);       
+       state->c = NULL;
+       state->addr = talloc(state, ctdb_sock_addr);
        if (state->addr == NULL) {
                ctdb_set_error(ctdb, "Out of memory at %s:%d",
                               __FILE__, __LINE__);
-               free(iface);
                talloc_free(state);
                return -1;
        }
        *state->addr = pip->addr;
+       state->target_pnn = pip->pnn;
        state->vnn   = vnn;
 
        vnn->update_in_flight = true;
@@ -979,7 +1015,6 @@ int32_t ctdb_control_release_ip(struct ctdb_context *ctdb,
                                         iface,
                                         ctdb_addr_to_str(&pip->addr),
                                         vnn->public_netmask_bits);
-       free(iface);
        if (ret != 0) {
                DEBUG(DEBUG_ERR,(__location__ " Failed to release IP %s on interface %s\n",
                        ctdb_addr_to_str(&pip->addr),
@@ -990,6 +1025,7 @@ int32_t ctdb_control_release_ip(struct ctdb_context *ctdb,
 
        /* tell the control that we will be reply asynchronously */
        *async_reply = true;
+       state->c = talloc_steal(state, c);
        return 0;
 }
 
@@ -999,66 +1035,66 @@ static int ctdb_add_public_address(struct ctdb_context *ctdb,
                                   bool check_address)
 {
        struct ctdb_vnn      *vnn;
-       uint32_t num = 0;
        char *tmp;
        const char *iface;
-       int i;
-       int ret;
-
-       tmp = strdup(ifaces);
-       for (iface = strtok(tmp, ","); iface; iface = strtok(NULL, ",")) {
-               if (!ctdb_sys_check_iface_exists(iface)) {
-                       DEBUG(DEBUG_CRIT,("Interface %s does not exist. Can not add public-address : %s\n", iface, ctdb_addr_to_str(addr)));
-                       free(tmp);
-                       return -1;
-               }
-       }
-       free(tmp);
 
-       /* Verify that we don't have an entry for this ip yet */
-       for (vnn=ctdb->vnn;vnn;vnn=vnn->next) {
+       /* Verify that we don't have an entry for this IP yet */
+       for (vnn = ctdb->vnn; vnn != NULL; vnn = vnn->next) {
                if (ctdb_same_sockaddr(addr, &vnn->public_address)) {
-                       DEBUG(DEBUG_CRIT,("Same ip '%s' specified multiple times in the public address list \n", 
-                               ctdb_addr_to_str(addr)));
+                       DEBUG(DEBUG_ERR,
+                             ("Duplicate public IP address '%s'\n",
+                              ctdb_addr_to_str(addr)));
                        return -1;
-               }               
+               }
        }
 
-       /* create a new vnn structure for this ip address */
+       /* Create a new VNN structure for this IP address */
        vnn = talloc_zero(ctdb, struct ctdb_vnn);
-       CTDB_NO_MEMORY_FATAL(ctdb, vnn);
-       vnn->ifaces = talloc_array(vnn, const char *, num + 2);
+       if (vnn == NULL) {
+               DEBUG(DEBUG_ERR, (__location__ " out of memory\n"));
+               return -1;
+       }
        tmp = talloc_strdup(vnn, ifaces);
-       CTDB_NO_MEMORY_FATAL(ctdb, tmp);
-       for (iface = strtok(tmp, ","); iface; iface = strtok(NULL, ",")) {
-               vnn->ifaces = talloc_realloc(vnn, vnn->ifaces, const char *, num + 2);
-               CTDB_NO_MEMORY_FATAL(ctdb, vnn->ifaces);
-               vnn->ifaces[num] = talloc_strdup(vnn, iface);
-               CTDB_NO_MEMORY_FATAL(ctdb, vnn->ifaces[num]);
-               num++;
+       if (tmp == NULL) {
+               DEBUG(DEBUG_ERR, (__location__ " out of memory\n"));
+               talloc_free(vnn);
+               return -1;
        }
-       talloc_free(tmp);
-       vnn->ifaces[num] = NULL;
-       vnn->public_address      = *addr;
-       vnn->public_netmask_bits = mask;
-       vnn->pnn                 = -1;
-       if (check_address) {
-               if (ctdb_sys_have_ip(addr)) {
-                       DEBUG(DEBUG_ERR,("We are already hosting public address '%s'. setting PNN to ourself:%d\n", ctdb_addr_to_str(addr), ctdb->pnn));
-                       vnn->pnn = ctdb->pnn;
+       for (iface = strtok(tmp, ","); iface; iface = strtok(NULL, ",")) {
+               struct vnn_interface *vnn_iface;
+               struct ctdb_interface *i;
+               if (!ctdb_sys_check_iface_exists(iface)) {
+                       DEBUG(DEBUG_ERR,
+                             ("Unknown interface %s for public address %s\n",
+                              iface, ctdb_addr_to_str(addr)));
+                       talloc_free(vnn);
+                       return -1;
                }
-       }
 
-       for (i=0; vnn->ifaces[i]; i++) {
-               ret = ctdb_add_local_iface(ctdb, vnn->ifaces[i]);
-               if (ret != 0) {
-                       DEBUG(DEBUG_CRIT, (__location__ " failed to add iface[%s] "
-                                          "for public_address[%s]\n",
-                                          vnn->ifaces[i], ctdb_addr_to_str(addr)));
+               i = ctdb_add_local_iface(ctdb, iface);
+               if (i == NULL) {
+                       DEBUG(DEBUG_ERR,
+                             ("Failed to add interface '%s' "
+                              "for public address %s\n",
+                              iface, ctdb_addr_to_str(addr)));
+                       talloc_free(vnn);
+                       return -1;
+               }
+
+               vnn_iface = talloc_zero(vnn, struct vnn_interface);
+               if (vnn_iface == NULL) {
+                       DEBUG(DEBUG_ERR, (__location__ " out of memory\n"));
                        talloc_free(vnn);
                        return -1;
                }
+
+               vnn_iface->iface = i;
+               DLIST_ADD_END(vnn->ifaces, vnn_iface);
        }
+       talloc_free(tmp);
+       vnn->public_address      = *addr;
+       vnn->public_netmask_bits = mask;
+       vnn->pnn                 = -1;
 
        DLIST_ADD(ctdb->vnn, vnn);
 
@@ -1132,712 +1168,6 @@ int ctdb_set_public_addresses(struct ctdb_context *ctdb, bool check_addresses)
        return 0;
 }
 
-static void *add_ip_callback(void *parm, void *data)
-{
-       struct public_ip_list *this_ip = parm;
-       struct public_ip_list *prev_ip = data;
-
-       if (prev_ip == NULL) {
-               return parm;
-       }
-       if (this_ip->pnn == -1) {
-               this_ip->pnn = prev_ip->pnn;
-       }
-
-       return parm;
-}
-
-static int getips_count_callback(void *param, void *data)
-{
-       struct public_ip_list **ip_list = (struct public_ip_list **)param;
-       struct public_ip_list *new_ip = (struct public_ip_list *)data;
-
-       new_ip->next = *ip_list;
-       *ip_list     = new_ip;
-       return 0;
-}
-
-static int verify_remote_ip_allocation(struct ctdb_context *ctdb,
-                                      struct ctdb_public_ip_list *ips,
-                                      uint32_t pnn);
-
-static int ctdb_reload_remote_public_ips(struct ctdb_context *ctdb,
-                                        struct ipalloc_state *ipalloc_state,
-                                        struct ctdb_node_map_old *nodemap)
-{
-       int j;
-       int ret;
-       struct ctdb_public_ip_list_old *ip_list;
-
-       if (ipalloc_state->num != nodemap->num) {
-               DEBUG(DEBUG_ERR,
-                     (__location__
-                      " ipalloc_state->num (%d) != nodemap->num (%d) invalid param\n",
-                      ipalloc_state->num, nodemap->num));
-               return -1;
-       }
-
-       for (j=0; j<nodemap->num; j++) {
-               if (nodemap->nodes[j].flags & NODE_FLAGS_INACTIVE) {
-                       continue;
-               }
-
-               /* Retrieve the list of known public IPs from the node */
-               ret = ctdb_ctrl_get_public_ips_flags(ctdb,
-                                       TAKEOVER_TIMEOUT(),
-                                       j,
-                                       ipalloc_state->known_public_ips,
-                                       0,
-                                       &ip_list);
-               if (ret != 0) {
-                       DEBUG(DEBUG_ERR,
-                             ("Failed to read known public IPs from node: %u\n",
-                              j));
-                       return -1;
-               }
-               ipalloc_state->known_public_ips[j].num = ip_list->num;
-               /* This could be copied and freed.  However, ip_list
-                * is allocated off ipalloc_state->known_public_ips,
-                * so this is a safe hack.  This will go away in a
-                * while anyway... */
-               ipalloc_state->known_public_ips[j].ip = &ip_list->ips[0];
-
-               if (ctdb->do_checkpublicip) {
-                       verify_remote_ip_allocation(
-                               ctdb,
-                               &ipalloc_state->known_public_ips[j],
-                               j);
-               }
-
-               /* Retrieve the list of available public IPs from the node */
-               ret = ctdb_ctrl_get_public_ips_flags(ctdb,
-                                       TAKEOVER_TIMEOUT(),
-                                       j,
-                                       ipalloc_state->available_public_ips,
-                                       CTDB_PUBLIC_IP_FLAGS_ONLY_AVAILABLE,
-                                       &ip_list);
-               if (ret != 0) {
-                       DEBUG(DEBUG_ERR,
-                             ("Failed to read available public IPs from node: %u\n",
-                              j));
-                       return -1;
-               }
-               ipalloc_state->available_public_ips[j].num = ip_list->num;
-               /* This could be copied and freed.  However, ip_list
-                * is allocated off ipalloc_state->available_public_ips,
-                * so this is a safe hack.  This will go away in a
-                * while anyway... */
-               ipalloc_state->available_public_ips[j].ip = &ip_list->ips[0];
-       }
-
-       return 0;
-}
-
-static struct public_ip_list *
-create_merged_ip_list(struct ctdb_context *ctdb, struct ipalloc_state *ipalloc_state)
-{
-       int i, j;
-       struct public_ip_list *ip_list;
-       struct ctdb_public_ip_list *public_ips;
-
-       TALLOC_FREE(ctdb->ip_tree);
-       ctdb->ip_tree = trbt_create(ctdb, 0);
-
-       for (i=0; i < ctdb->num_nodes; i++) {
-
-               if (ctdb->nodes[i]->flags & NODE_FLAGS_DELETED) {
-                       continue;
-               }
-
-               /* there were no public ips for this node */
-               if (ipalloc_state->known_public_ips == NULL) {
-                       continue;
-               }
-
-               public_ips = &ipalloc_state->known_public_ips[i];
-
-               for (j=0; j < public_ips->num; j++) {
-                       struct public_ip_list *tmp_ip;
-
-                       tmp_ip = talloc_zero(ctdb->ip_tree, struct public_ip_list);
-                       CTDB_NO_MEMORY_NULL(ctdb, tmp_ip);
-                       /* Do not use information about IP addresses hosted
-                        * on other nodes, it may not be accurate */
-                       if (public_ips->ip[j].pnn == ctdb->nodes[i]->pnn) {
-                               tmp_ip->pnn = public_ips->ip[j].pnn;
-                       } else {
-                               tmp_ip->pnn = -1;
-                       }
-                       tmp_ip->addr = public_ips->ip[j].addr;
-                       tmp_ip->next = NULL;
-
-                       trbt_insertarray32_callback(ctdb->ip_tree,
-                               IP_KEYLEN, ip_key(&public_ips->ip[j].addr),
-                               add_ip_callback,
-                               tmp_ip);
-               }
-       }
-
-       ip_list = NULL;
-       trbt_traversearray32(ctdb->ip_tree, IP_KEYLEN, getips_count_callback, &ip_list);
-
-       return ip_list;
-}
-
-static bool all_nodes_are_disabled(struct ctdb_node_map_old *nodemap)
-{
-       int i;
-
-       for (i=0;i<nodemap->num;i++) {
-               if (!(nodemap->nodes[i].flags & (NODE_FLAGS_INACTIVE|NODE_FLAGS_DISABLED))) {
-                       /* Found one completely healthy node */
-                       return false;
-               }
-       }
-
-       return true;
-}
-
-struct get_tunable_callback_data {
-       const char *tunable;
-       uint32_t *out;
-       bool fatal;
-};
-
-static void get_tunable_callback(struct ctdb_context *ctdb, uint32_t pnn,
-                                int32_t res, TDB_DATA outdata,
-                                void *callback)
-{
-       struct get_tunable_callback_data *cd =
-               (struct get_tunable_callback_data *)callback;
-       int size;
-
-       if (res != 0) {
-               /* Already handled in fail callback */
-               return;
-       }
-
-       if (outdata.dsize != sizeof(uint32_t)) {
-               DEBUG(DEBUG_ERR,("Wrong size of returned data when reading \"%s\" tunable from node %d. Expected %d bytes but received %d bytes\n",
-                                cd->tunable, pnn, (int)sizeof(uint32_t),
-                                (int)outdata.dsize));
-               cd->fatal = true;
-               return;
-       }
-
-       size = talloc_array_length(cd->out);
-       if (pnn >= size) {
-               DEBUG(DEBUG_ERR,("Got %s reply from node %d but nodemap only has %d entries\n",
-                                cd->tunable, pnn, size));
-               return;
-       }
-
-               
-       cd->out[pnn] = *(uint32_t *)outdata.dptr;
-}
-
-static void get_tunable_fail_callback(struct ctdb_context *ctdb, uint32_t pnn,
-                                      int32_t res, TDB_DATA outdata,
-                                      void *callback)
-{
-       struct get_tunable_callback_data *cd =
-               (struct get_tunable_callback_data *)callback;
-
-       switch (res) {
-       case -ETIME:
-               DEBUG(DEBUG_ERR,
-                     ("Timed out getting tunable \"%s\" from node %d\n",
-                      cd->tunable, pnn));
-               cd->fatal = true;
-               break;
-       case -EINVAL:
-       case -1:
-               DEBUG(DEBUG_WARNING,
-                     ("Tunable \"%s\" not implemented on node %d\n",
-                      cd->tunable, pnn));
-               break;
-       default:
-               DEBUG(DEBUG_ERR,
-                     ("Unexpected error getting tunable \"%s\" from node %d\n",
-                      cd->tunable, pnn));
-               cd->fatal = true;
-       }
-}
-
-static uint32_t *get_tunable_from_nodes(struct ctdb_context *ctdb,
-                                       TALLOC_CTX *tmp_ctx,
-                                       struct ctdb_node_map_old *nodemap,
-                                       const char *tunable,
-                                       uint32_t default_value)
-{
-       TDB_DATA data;
-       struct ctdb_control_get_tunable *t;
-       uint32_t *nodes;
-       uint32_t *tvals;
-       struct get_tunable_callback_data callback_data;
-       int i;
-
-       tvals = talloc_array(tmp_ctx, uint32_t, nodemap->num);
-       CTDB_NO_MEMORY_NULL(ctdb, tvals);
-       for (i=0; i<nodemap->num; i++) {
-               tvals[i] = default_value;
-       }
-               
-       callback_data.out = tvals;
-       callback_data.tunable = tunable;
-       callback_data.fatal = false;
-
-       data.dsize = offsetof(struct ctdb_control_get_tunable, name) + strlen(tunable) + 1;
-       data.dptr  = talloc_size(tmp_ctx, data.dsize);
-       t = (struct ctdb_control_get_tunable *)data.dptr;
-       t->length = strlen(tunable)+1;
-       memcpy(t->name, tunable, t->length);
-       nodes = list_of_connected_nodes(ctdb, nodemap, tmp_ctx, true);
-       if (ctdb_client_async_control(ctdb, CTDB_CONTROL_GET_TUNABLE,
-                                     nodes, 0, TAKEOVER_TIMEOUT(),
-                                     false, data,
-                                     get_tunable_callback,
-                                     get_tunable_fail_callback,
-                                     &callback_data) != 0) {
-               if (callback_data.fatal) {
-                       talloc_free(tvals);
-                       tvals = NULL;
-               }
-       }
-       talloc_free(nodes);
-       talloc_free(data.dptr);
-
-       return tvals;
-}
-
-/* Set internal flags for IP allocation:
- *   Clear ip flags
- *   Set NOIPTAKOVER ip flags from per-node NoIPTakeover tunable
- *   Set NOIPHOST ip flag for each INACTIVE node
- *   if all nodes are disabled:
- *     Set NOIPHOST ip flags from per-node NoIPHostOnAllDisabled tunable
- *   else
- *     Set NOIPHOST ip flags for disabled nodes
- */
-static void set_ipflags_internal(struct ipalloc_state *ipalloc_state,
-                                struct ctdb_node_map_old *nodemap,
-                                uint32_t *tval_noiptakeover,
-                                uint32_t *tval_noiphostonalldisabled)
-{
-       int i;
-
-       for (i=0;i<nodemap->num;i++) {
-               /* Can not take IPs on node with NoIPTakeover set */
-               if (tval_noiptakeover[i] != 0) {
-                       ipalloc_state->noiptakeover[i] = true;
-               }
-
-               /* Can not host IPs on INACTIVE node */
-               if (nodemap->nodes[i].flags & NODE_FLAGS_INACTIVE) {
-                       ipalloc_state->noiphost[i] = true;
-               }
-       }
-
-       if (all_nodes_are_disabled(nodemap)) {
-               /* If all nodes are disabled, can not host IPs on node
-                * with NoIPHostOnAllDisabled set
-                */
-               for (i=0;i<nodemap->num;i++) {
-                       if (tval_noiphostonalldisabled[i] != 0) {
-                               ipalloc_state->noiphost[i] = true;
-                       }
-               }
-       } else {
-               /* If some nodes are not disabled, then can not host
-                * IPs on DISABLED node
-                */
-               for (i=0;i<nodemap->num;i++) {
-                       if (nodemap->nodes[i].flags & NODE_FLAGS_DISABLED) {
-                               ipalloc_state->noiphost[i] = true;
-                       }
-               }
-       }
-}
-
-static bool set_ipflags(struct ctdb_context *ctdb,
-                       struct ipalloc_state *ipalloc_state,
-                       struct ctdb_node_map_old *nodemap)
-{
-       uint32_t *tval_noiptakeover;
-       uint32_t *tval_noiphostonalldisabled;
-
-       tval_noiptakeover = get_tunable_from_nodes(ctdb, ipalloc_state, nodemap,
-                                                  "NoIPTakeover", 0);
-       if (tval_noiptakeover == NULL) {
-               return false;
-       }
-
-       tval_noiphostonalldisabled =
-               get_tunable_from_nodes(ctdb, ipalloc_state, nodemap,
-                                      "NoIPHostOnAllDisabled", 0);
-       if (tval_noiphostonalldisabled == NULL) {
-               /* Caller frees tmp_ctx */
-               return false;
-       }
-
-       set_ipflags_internal(ipalloc_state, nodemap,
-                            tval_noiptakeover,
-                            tval_noiphostonalldisabled);
-
-       talloc_free(tval_noiptakeover);
-       talloc_free(tval_noiphostonalldisabled);
-
-       return true;
-}
-
-static struct ipalloc_state * ipalloc_state_init(struct ctdb_context *ctdb,
-                                                TALLOC_CTX *mem_ctx)
-{
-       struct ipalloc_state *ipalloc_state =
-               talloc_zero(mem_ctx, struct ipalloc_state);
-       if (ipalloc_state == NULL) {
-               DEBUG(DEBUG_ERR, (__location__ " Out of memory\n"));
-               return NULL;
-       }
-
-       ipalloc_state->num = ctdb->num_nodes;
-
-       ipalloc_state->known_public_ips =
-               talloc_zero_array(ipalloc_state,
-                                 struct ctdb_public_ip_list,
-                                 ipalloc_state->num);
-       if (ipalloc_state->known_public_ips == NULL) {
-               DEBUG(DEBUG_ERR, (__location__ " Out of memory\n"));
-               goto fail;
-       }
-
-       ipalloc_state->available_public_ips =
-               talloc_zero_array(ipalloc_state,
-                                 struct ctdb_public_ip_list,
-                                 ipalloc_state->num);
-       if (ipalloc_state->available_public_ips == NULL) {
-               DEBUG(DEBUG_ERR, (__location__ " Out of memory\n"));
-               goto fail;
-       }
-       ipalloc_state->noiptakeover =
-               talloc_zero_array(ipalloc_state,
-                                 bool,
-                                 ipalloc_state->num);
-       if (ipalloc_state->noiptakeover == NULL) {
-               DEBUG(DEBUG_ERR, (__location__ " Out of memory\n"));
-               goto fail;
-       }
-       ipalloc_state->noiphost =
-               talloc_zero_array(ipalloc_state,
-                                 bool,
-                                 ipalloc_state->num);
-       if (ipalloc_state->noiphost == NULL) {
-               DEBUG(DEBUG_ERR, (__location__ " Out of memory\n"));
-               goto fail;
-       }
-
-       if (1 == ctdb->tunable.lcp2_public_ip_assignment) {
-               ipalloc_state->algorithm = IPALLOC_LCP2;
-       } else if (1 == ctdb->tunable.deterministic_public_ips) {
-               ipalloc_state->algorithm = IPALLOC_DETERMINISTIC;
-       } else {
-               ipalloc_state->algorithm = IPALLOC_NONDETERMINISTIC;
-       }
-
-       ipalloc_state->no_ip_failback = ctdb->tunable.no_ip_failback;
-
-       return ipalloc_state;
-fail:
-       talloc_free(ipalloc_state);
-       return NULL;
-}
-
-struct takeover_callback_data {
-       uint32_t num_nodes;
-       bool *node_failed;
-       client_async_callback fail_callback;
-       void *fail_callback_data;
-};
-
-static struct takeover_callback_data *
-takeover_callback_data_init(TALLOC_CTX *mem_ctx,
-                           uint32_t num_nodes,
-                           client_async_callback fail_callback,
-                           void *callback_data)
-{
-       static struct takeover_callback_data *takeover_data;
-
-       takeover_data = talloc_zero(mem_ctx, struct takeover_callback_data);
-       if (takeover_data == NULL) {
-               DEBUG(DEBUG_ERR, (__location__ " out of memory\n"));
-               return NULL;
-       }
-
-       takeover_data->node_failed = talloc_zero_array(takeover_data,
-                                                      bool, num_nodes);
-       if (takeover_data->node_failed == NULL) {
-               DEBUG(DEBUG_ERR, (__location__ " out of memory\n"));
-               talloc_free(takeover_data);
-               return NULL;
-       }
-
-       takeover_data->num_nodes = num_nodes;
-       takeover_data->fail_callback = fail_callback;
-       takeover_data->fail_callback_data = callback_data;
-
-       return takeover_data;
-}
-
-static void takeover_run_fail_callback(struct ctdb_context *ctdb,
-                                      uint32_t node_pnn, int32_t res,
-                                      TDB_DATA outdata, void *callback_data)
-{
-       struct takeover_callback_data *cd =
-               talloc_get_type_abort(callback_data,
-                                     struct takeover_callback_data);
-
-       if (node_pnn >= cd->num_nodes) {
-               DEBUG(DEBUG_ERR, (__location__ " invalid PNN %u\n", node_pnn));
-               return;
-       }
-
-       if (!cd->node_failed[node_pnn]) {
-               cd->node_failed[node_pnn] = true;
-               cd->fail_callback(ctdb, node_pnn, res, outdata,
-                                 cd->fail_callback_data);
-       }
-}
-
-/*
- * Recalculate the allocation of public IPs to nodes and have the
- * nodes host their allocated addresses.
- *
- * - Allocate memory for IP allocation state, including per node
- *   arrays
- * - Populate IP allocation algorithm in IP allocation state
- * - Populate local value of tunable NoIPFailback in IP allocation
-     state - this is really a cluster-wide configuration variable and
-     only the value form the master node is used
- * - Retrieve tunables NoIPTakeover and NoIPHostOnAllDisabled from all
- *   connected nodes - this is done separately so tunable values can
- *   be faked in unit testing
- * - Populate NoIPTakover tunable in IP allocation state
- * - Populate NoIPHost in IP allocation state, derived from node flags
- *   and NoIPHostOnAllDisabled tunable
- * - Retrieve and populate known and available IP lists in IP
- *   allocation state
- * - If no available IP addresses then early exit
- * - Build list of (known IPs, currently assigned node)
- * - Populate list of nodes to force rebalance - internal structure,
- *   currently no way to fetch, only used by LCP2 for nodes that have
- *   had new IP addresses added
- * - Run IP allocation algorithm
- * - Send RELEASE_IP to all nodes for IPs they should not host
- * - Send TAKE_IP to all nodes for IPs they should host
- * - Send IPREALLOCATED to all nodes (with backward compatibility hack)
- */
-int ctdb_takeover_run(struct ctdb_context *ctdb, struct ctdb_node_map_old *nodemap,
-                     uint32_t *force_rebalance_nodes,
-                     client_async_callback fail_callback, void *callback_data)
-{
-       int i, ret;
-       struct ctdb_public_ip ip;
-       uint32_t *nodes;
-       struct public_ip_list *all_ips, *tmp_ip;
-       TDB_DATA data;
-       struct timeval timeout;
-       struct client_async_data *async_data;
-       struct ctdb_client_control_state *state;
-       TALLOC_CTX *tmp_ctx = talloc_new(ctdb);
-       struct ipalloc_state *ipalloc_state;
-       struct takeover_callback_data *takeover_data;
-       bool can_host_ips;
-
-       /*
-        * ip failover is completely disabled, just send out the 
-        * ipreallocated event.
-        */
-       if (ctdb->tunable.disable_ip_failover != 0) {
-               goto ipreallocated;
-       }
-
-       ipalloc_state = ipalloc_state_init(ctdb, tmp_ctx);
-       if (ipalloc_state == NULL) {
-               talloc_free(tmp_ctx);
-               return -1;
-       }
-
-       if (!set_ipflags(ctdb, ipalloc_state, nodemap)) {
-               DEBUG(DEBUG_ERR,("Failed to set IP flags - aborting takeover run\n"));
-               talloc_free(tmp_ctx);
-               return -1;
-       }
-
-       /* Fetch known/available public IPs from each active node */
-       ret = ctdb_reload_remote_public_ips(ctdb, ipalloc_state, nodemap);
-       if (ret != 0) {
-               talloc_free(tmp_ctx);
-               return -1;
-       }
-
-       /* Short-circuit IP allocation if no node has available IPs */
-       can_host_ips = false;
-       for (i=0; i < ipalloc_state->num; i++) {
-               if (ipalloc_state->available_public_ips[i].num != 0) {
-                       can_host_ips = true;
-               }
-       }
-       if (!can_host_ips) {
-               DEBUG(DEBUG_WARNING,("No nodes available to host public IPs yet\n"));
-               goto ipreallocated;
-       }
-
-       /* since nodes only know about those public addresses that
-          can be served by that particular node, no single node has
-          a full list of all public addresses that exist in the cluster.
-          Walk over all node structures and create a merged list of
-          all public addresses that exist in the cluster.
-
-          keep the tree of ips around as ctdb->ip_tree
-       */
-       all_ips = create_merged_ip_list(ctdb, ipalloc_state);
-       ipalloc_state->all_ips = all_ips;
-
-       ipalloc_state->force_rebalance_nodes = force_rebalance_nodes;
-
-       /* Do the IP reassignment calculations */
-       ipalloc(ipalloc_state);
-
-       /* Now tell all nodes to release any public IPs should not
-        * host.  This will be a NOOP on nodes that don't currently
-        * hold the given IP.
-        */
-       takeover_data = takeover_callback_data_init(tmp_ctx,
-                                                   nodemap->num,
-                                                   fail_callback,
-                                                   callback_data);
-       if (takeover_data == NULL) {
-               talloc_free(tmp_ctx);
-               return -1;
-       }
-
-       async_data = talloc_zero(tmp_ctx, struct client_async_data);
-       CTDB_NO_MEMORY_FATAL(ctdb, async_data);
-
-       async_data->fail_callback = takeover_run_fail_callback;
-       async_data->callback_data = takeover_data;
-
-       ZERO_STRUCT(ip); /* Avoid valgrind warnings for union */
-
-       /* Send a RELEASE_IP to all nodes that should not be hosting
-        * each IP.  For each IP, all but one of these will be
-        * redundant.  However, the redundant ones are used to tell
-        * nodes which node should be hosting the IP so that commands
-        * like "ctdb ip" can display a particular nodes idea of who
-        * is hosting what. */
-       for (i=0;i<nodemap->num;i++) {
-               /* don't talk to unconnected nodes, but do talk to banned nodes */
-               if (nodemap->nodes[i].flags & NODE_FLAGS_DISCONNECTED) {
-                       continue;
-               }
-
-               for (tmp_ip=all_ips;tmp_ip;tmp_ip=tmp_ip->next) {
-                       if (tmp_ip->pnn == nodemap->nodes[i].pnn) {
-                               /* This node should be serving this
-                                  vnn so don't tell it to release the ip
-                               */
-                               continue;
-                       }
-                       ip.pnn  = tmp_ip->pnn;
-                       ip.addr = tmp_ip->addr;
-
-                       timeout = TAKEOVER_TIMEOUT();
-                       data.dsize = sizeof(ip);
-                       data.dptr  = (uint8_t *)&ip;
-                       state = ctdb_control_send(ctdb, nodemap->nodes[i].pnn,
-                                                 0, CTDB_CONTROL_RELEASE_IP, 0,
-                                                 data, async_data,
-                                                 &timeout, NULL);
-                       if (state == NULL) {
-                               DEBUG(DEBUG_ERR,(__location__ " Failed to call async control CTDB_CONTROL_RELEASE_IP to node %u\n", nodemap->nodes[i].pnn));
-                               talloc_free(tmp_ctx);
-                               return -1;
-                       }
-
-                       ctdb_client_async_add(async_data, state);
-               }
-       }
-       if (ctdb_client_async_wait(ctdb, async_data) != 0) {
-               DEBUG(DEBUG_ERR,(__location__ " Async control CTDB_CONTROL_RELEASE_IP failed\n"));
-               talloc_free(tmp_ctx);
-               return -1;
-       }
-       talloc_free(async_data);
-
-
-       /* For each IP, send a TAKOVER_IP to the node that should be
-        * hosting it.  Many of these will often be redundant (since
-        * the allocation won't have changed) but they can be useful
-        * to recover from inconsistencies. */
-       async_data = talloc_zero(tmp_ctx, struct client_async_data);
-       CTDB_NO_MEMORY_FATAL(ctdb, async_data);
-
-       async_data->fail_callback = fail_callback;
-       async_data->callback_data = callback_data;
-
-       for (tmp_ip=all_ips;tmp_ip;tmp_ip=tmp_ip->next) {
-               if (tmp_ip->pnn == -1) {
-                       /* this IP won't be taken over */
-                       continue;
-               }
-
-               ip.pnn  = tmp_ip->pnn;
-               ip.addr = tmp_ip->addr;
-
-               timeout = TAKEOVER_TIMEOUT();
-               data.dsize = sizeof(ip);
-               data.dptr  = (uint8_t *)&ip;
-               state = ctdb_control_send(ctdb, tmp_ip->pnn,
-                                         0, CTDB_CONTROL_TAKEOVER_IP, 0,
-                                         data, async_data, &timeout, NULL);
-               if (state == NULL) {
-                       DEBUG(DEBUG_ERR,(__location__ " Failed to call async control CTDB_CONTROL_TAKEOVER_IP to node %u\n", tmp_ip->pnn));
-                       talloc_free(tmp_ctx);
-                       return -1;
-               }
-
-               ctdb_client_async_add(async_data, state);
-       }
-       if (ctdb_client_async_wait(ctdb, async_data) != 0) {
-               DEBUG(DEBUG_ERR,(__location__ " Async control CTDB_CONTROL_TAKEOVER_IP failed\n"));
-               talloc_free(tmp_ctx);
-               return -1;
-       }
-
-ipreallocated:
-       /*
-        * Tell all nodes to run eventscripts to process the
-        * "ipreallocated" event.  This can do a lot of things,
-        * including restarting services to reconfigure them if public
-        * IPs have moved.  Once upon a time this event only used to
-        * update natgw.
-        */
-       nodes = list_of_connected_nodes(ctdb, nodemap, tmp_ctx, true);
-       ret = ctdb_client_async_control(ctdb, CTDB_CONTROL_IPREALLOCATED,
-                                       nodes, 0, TAKEOVER_TIMEOUT(),
-                                       false, tdb_null,
-                                       NULL, fail_callback,
-                                       &callback_data);
-       if (ret != 0) {
-               DEBUG(DEBUG_ERR,
-                     ("Async CTDB_CONTROL_IPREALLOCATED control failed\n"));
-       }
-
-       talloc_free(tmp_ctx);
-       return ret;
-}
-
-
 /*
   destroy a ctdb_client_ip structure
  */
@@ -2082,7 +1412,7 @@ static void ctdb_remove_connection(struct ctdb_vnn *vnn, struct ctdb_connection
           and we don't need to do anything
         */
        if (vnn->tcp_array == NULL) {
-               DEBUG(DEBUG_INFO,("Trying to remove tickle that doesnt exist (array is empty) %s:%u\n",
+               DEBUG(DEBUG_INFO,("Trying to remove tickle that doesn't exist (array is empty) %s:%u\n",
                        ctdb_addr_to_str(&conn->dst),
                        ntohs(conn->dst.ip.sin_port)));
                return;
@@ -2094,7 +1424,7 @@ static void ctdb_remove_connection(struct ctdb_vnn *vnn, struct ctdb_connection
         */
        tcpp = ctdb_tcp_find(vnn->tcp_array, conn);
        if (tcpp == NULL) {
-               DEBUG(DEBUG_INFO,("Trying to remove tickle that doesnt exist %s:%u\n",
+               DEBUG(DEBUG_INFO,("Trying to remove tickle that doesn't exist %s:%u\n",
                        ctdb_addr_to_str(&conn->dst),
                        ntohs(conn->dst.ip.sin_port)));
                return;
@@ -2153,24 +1483,23 @@ int32_t ctdb_control_tcp_remove(struct ctdb_context *ctdb, TDB_DATA indata)
 }
 
 
+static void ctdb_send_set_tcp_tickles_for_all(struct ctdb_context *ctdb,
+                                             bool force);
+
 /*
   Called when another daemon starts - causes all tickles for all
   public addresses we are serving to be sent to the new node on the
-  next check.  This actually causes the next scheduled call to
-  tdb_update_tcp_tickles() to update all nodes.  This is simple and
+  next check.  This actually causes the tickles to be sent to the
+  other node immediately.  In case there is an error, the periodic
+  timer will send the updates on timer event.  This is simple and
   doesn't require careful error handling.
  */
 int32_t ctdb_control_startup(struct ctdb_context *ctdb, uint32_t pnn)
 {
-       struct ctdb_vnn *vnn;
-
        DEBUG(DEBUG_INFO, ("Received startup control from node %lu\n",
                           (unsigned long) pnn));
 
-       for (vnn = ctdb->vnn; vnn != NULL; vnn = vnn->next) {
-               vnn->tcp_update_needed = true;
-       }
-
+       ctdb_send_set_tcp_tickles_for_all(ctdb, true);
        return 0;
 }
 
@@ -2214,22 +1543,21 @@ void ctdb_takeover_client_destructor_hook(struct ctdb_client *client)
 
 void ctdb_release_all_ips(struct ctdb_context *ctdb)
 {
-       struct ctdb_vnn *vnn;
+       struct ctdb_vnn *vnn, *next;
        int count = 0;
-       TDB_DATA data;
 
        if (ctdb->tunable.disable_ip_failover == 1) {
                return;
        }
 
-       for (vnn=ctdb->vnn;vnn;vnn=vnn->next) {
+       for (vnn = ctdb->vnn; vnn != NULL; vnn = next) {
+               /* vnn can be freed below in release_ip_post() */
+               next = vnn->next;
+
                if (!ctdb_sys_have_ip(&vnn->public_address)) {
                        ctdb_vnn_unassign_iface(ctdb, vnn);
                        continue;
                }
-               if (!vnn->iface) {
-                       continue;
-               }
 
                /* Don't allow multiple releases at once.  Some code,
                 * particularly ctdb_tickle_sentenced_connections() is
@@ -2237,7 +1565,7 @@ void ctdb_release_all_ips(struct ctdb_context *ctdb)
                if (vnn->update_in_flight) {
                        DEBUG(DEBUG_WARNING,
                              (__location__
-                              " Not releasing IP %s/%u on interface %s, an update is already in progess\n",
+                              " Not releasing IP %s/%u on interface %s, an update is already in progress\n",
                                    ctdb_addr_to_str(&vnn->public_address),
                                    vnn->public_netmask_bits,
                                    ctdb_vnn_iface_string(vnn)));
@@ -2251,21 +1579,26 @@ void ctdb_release_all_ips(struct ctdb_context *ctdb)
                                    ctdb_vnn_iface_string(vnn)));
 
                ctdb_event_script_args(ctdb, CTDB_EVENT_RELEASE_IP, "%s %s %u",
-                                 ctdb_vnn_iface_string(vnn),
-                                 ctdb_addr_to_str(&vnn->public_address),
-                                 vnn->public_netmask_bits);
-
-               data.dptr = (uint8_t *)talloc_strdup(
-                               vnn, ctdb_addr_to_str(&vnn->public_address));
-               if (data.dptr != NULL) {
-                       data.dsize = strlen((char *)data.dptr) + 1;
-                       ctdb_daemon_send_message(ctdb, ctdb->pnn,
-                                                CTDB_SRVID_RELEASE_IP, data);
-                       talloc_free(data.dptr);
+                                      ctdb_vnn_iface_string(vnn),
+                                      ctdb_addr_to_str(&vnn->public_address),
+                                      vnn->public_netmask_bits);
+               /* releaseip timeouts are converted to success, so to
+                * detect failures just check if the IP address is
+                * still there...
+                */
+               if (ctdb_sys_have_ip(&vnn->public_address)) {
+                       DEBUG(DEBUG_ERR,
+                             (__location__
+                              " IP address %s not released\n",
+                              ctdb_addr_to_str(&vnn->public_address)));
+                       vnn->update_in_flight = false;
+                       continue;
                }
 
-               ctdb_vnn_unassign_iface(ctdb, vnn);
-               vnn->update_in_flight = false;
+               vnn = release_ip_post(ctdb, vnn, &vnn->public_address);
+               if (vnn != NULL) {
+                       vnn->update_in_flight = false;
+               }
                count++;
        }
 
@@ -2328,6 +1661,7 @@ int32_t ctdb_control_get_public_ip_info(struct ctdb_context *ctdb,
        ctdb_sock_addr *addr;
        struct ctdb_public_ip_info_old *info;
        struct ctdb_vnn *vnn;
+       struct vnn_interface *iface;
 
        addr = (ctdb_sock_addr *)indata.dptr;
 
@@ -2341,7 +1675,7 @@ int32_t ctdb_control_get_public_ip_info(struct ctdb_context *ctdb,
 
        /* count how many public ip structures we have */
        num = 0;
-       for (;vnn->ifaces[num];) {
+       for (iface = vnn->ifaces; iface != NULL; iface = iface->next) {
                num++;
        }
 
@@ -2354,15 +1688,11 @@ int32_t ctdb_control_get_public_ip_info(struct ctdb_context *ctdb,
        info->ip.pnn = vnn->pnn;
        info->active_idx = 0xFFFFFFFF;
 
-       for (i=0; vnn->ifaces[i]; i++) {
+       i = 0;
+       for (iface = vnn->ifaces; iface != NULL; iface = iface->next) {
                struct ctdb_interface *cur;
 
-               cur = ctdb_find_iface(ctdb, vnn->ifaces[i]);
-               if (cur == NULL) {
-                       DEBUG(DEBUG_CRIT, (__location__ " internal error iface[%s] unknown\n",
-                                          vnn->ifaces[i]));
-                       return -1;
-               }
+               cur = iface->iface;
                if (vnn->iface == cur) {
                        info->active_idx = i;
                }
@@ -2371,6 +1701,8 @@ int32_t ctdb_control_get_public_ip_info(struct ctdb_context *ctdb,
                info->ifaces[i].name[sizeof(info->ifaces[i].name)-1] = '\0';
                info->ifaces[i].link_state = cur->link_up;
                info->ifaces[i].references = cur->references;
+
+               i++;
        }
        info->num = i;
        len = offsetof(struct ctdb_public_ip_info_old, ifaces) +
@@ -2465,7 +1797,7 @@ int32_t ctdb_control_set_iface_link(struct ctdb_context *ctdb,
                return 0;
        }
 
-       DEBUG(iface->link_up?DEBUG_ERR:DEBUG_NOTICE,
+       DEBUG(DEBUG_ERR,
              ("iface[%s] has changed it's link status %s => %s\n",
               iface->name,
               iface->link_up?"up":"down",
@@ -2650,43 +1982,53 @@ static int ctdb_send_set_tcp_tickles_for_ip(struct ctdb_context *ctdb,
        return ret;
 }
 
-
-/*
-  perform tickle updates if required
- */
-static void ctdb_update_tcp_tickles(struct tevent_context *ev,
-                                   struct tevent_timer *te,
-                                   struct timeval t, void *private_data)
+static void ctdb_send_set_tcp_tickles_for_all(struct ctdb_context *ctdb,
+                                             bool force)
 {
-       struct ctdb_context *ctdb = talloc_get_type(private_data, struct ctdb_context);
-       int ret;
        struct ctdb_vnn *vnn;
+       int ret;
 
-       for (vnn=ctdb->vnn;vnn;vnn=vnn->next) {
-               /* we only send out updates for public addresses that 
+       for (vnn = ctdb->vnn; vnn != NULL; vnn = vnn->next) {
+               /* we only send out updates for public addresses that
                   we have taken over
                 */
                if (ctdb->pnn != vnn->pnn) {
                        continue;
                }
+
                /* We only send out the updates if we need to */
-               if (!vnn->tcp_update_needed) {
+               if (!force && !vnn->tcp_update_needed) {
                        continue;
                }
+
                ret = ctdb_send_set_tcp_tickles_for_ip(ctdb,
                                                       &vnn->public_address,
                                                       vnn->tcp_array);
                if (ret != 0) {
-                       DEBUG(DEBUG_ERR,("Failed to send the tickle update for public address %s\n",
-                               ctdb_addr_to_str(&vnn->public_address)));
+                       D_ERR("Failed to send the tickle update for ip %s\n",
+                             ctdb_addr_to_str(&vnn->public_address));
+                       vnn->tcp_update_needed = true;
                } else {
-                       DEBUG(DEBUG_INFO,
-                             ("Sent tickle update for public address %s\n",
-                              ctdb_addr_to_str(&vnn->public_address)));
+                       D_INFO("Sent tickle update for ip %s\n",
+                              ctdb_addr_to_str(&vnn->public_address));
                        vnn->tcp_update_needed = false;
                }
        }
 
+}
+
+/*
+  perform tickle updates if required
+ */
+static void ctdb_update_tcp_tickles(struct tevent_context *ev,
+                                   struct tevent_timer *te,
+                                   struct timeval t, void *private_data)
+{
+       struct ctdb_context *ctdb = talloc_get_type(
+               private_data, struct ctdb_context);
+
+       ctdb_send_set_tcp_tickles_for_all(ctdb, false);
+
        tevent_add_timer(ctdb->ev, ctdb->tickle_update_context,
                         timeval_current_ofs(ctdb->tunable.tickle_update_interval, 0),
                         ctdb_update_tcp_tickles, ctdb);
@@ -2819,29 +2161,7 @@ int32_t ctdb_control_add_public_address(struct ctdb_context *ctdb, TDB_DATA inda
        return 0;
 }
 
-struct delete_ip_callback_state {
-       struct ctdb_req_control_old *c;
-};
-
-/*
-  called when releaseip event finishes for del_public_address
- */
-static void delete_ip_callback(struct ctdb_context *ctdb,
-                              int32_t status, TDB_DATA data,
-                              const char *errormsg,
-                              void *private_data)
-{
-       struct delete_ip_callback_state *state =
-               talloc_get_type(private_data, struct delete_ip_callback_state);
-
-       /* If release failed then fail. */
-       ctdb_request_control_reply(ctdb, state->c, NULL, status, errormsg);
-       talloc_free(private_data);
-}
-
-int32_t ctdb_control_del_public_address(struct ctdb_context *ctdb,
-                                       struct ctdb_req_control_old *c,
-                                       TDB_DATA indata, bool *async_reply)
+int32_t ctdb_control_del_public_address(struct ctdb_context *ctdb, TDB_DATA indata)
 {
        struct ctdb_addr_info_old *pub = (struct ctdb_addr_info_old *)indata.dptr;
        struct ctdb_vnn *vnn;
@@ -2868,49 +2188,13 @@ int32_t ctdb_control_del_public_address(struct ctdb_context *ctdb,
        for (vnn=ctdb->vnn;vnn;vnn=vnn->next) {
                if (ctdb_same_ip(&vnn->public_address, &pub->addr)) {
                        if (vnn->pnn == ctdb->pnn) {
-                               struct delete_ip_callback_state *state;
-                               struct ctdb_public_ip *ip;
-                               TDB_DATA data;
-                               int ret;
-
+                               /* This IP is currently being hosted.
+                                * Defer the deletion until the next
+                                * takeover run. "ctdb reloadips" will
+                                * always cause a takeover run.  "ctdb
+                                * delip" will now need an explicit
+                                * "ctdb ipreallocated" afterwards. */
                                vnn->delete_pending = true;
-
-                               state = talloc(ctdb,
-                                              struct delete_ip_callback_state);
-                               CTDB_NO_MEMORY(ctdb, state);
-                               state->c = c;
-
-                               ip = talloc(state, struct ctdb_public_ip);
-                               if (ip == NULL) {
-                                       DEBUG(DEBUG_ERR,
-                                             (__location__ " Out of memory\n"));
-                                       talloc_free(state);
-                                       return -1;
-                               }
-                               ip->pnn = -1;
-                               ip->addr = pub->addr;
-
-                               data.dsize = sizeof(struct ctdb_public_ip);
-                               data.dptr = (unsigned char *)ip;
-
-                               ret = ctdb_daemon_send_control(ctdb,
-                                                              ctdb_get_pnn(ctdb),
-                                                              0,
-                                                              CTDB_CONTROL_RELEASE_IP,
-                                                              0, 0,
-                                                              data,
-                                                              delete_ip_callback,
-                                                              state);
-                               if (ret == -1) {
-                                       DEBUG(DEBUG_ERR,
-                                             (__location__ "Unable to send "
-                                              "CTDB_CONTROL_RELEASE_IP\n"));
-                                       talloc_free(state);
-                                       return -1;
-                               }
-
-                               state->c = talloc_steal(state, c);
-                               *async_reply = true;
                        } else {
                                /* This IP is not hosted on the
                                 * current node so just delete it
@@ -2983,82 +2267,6 @@ int32_t ctdb_control_ipreallocated(struct ctdb_context *ctdb,
 }
 
 
-/* This function is called from the recovery daemon to verify that a remote
-   node has the expected ip allocation.
-   This is verified against ctdb->ip_tree
-*/
-static int verify_remote_ip_allocation(struct ctdb_context *ctdb,
-                                      struct ctdb_public_ip_list *ips,
-                                      uint32_t pnn)
-{
-       struct public_ip_list *tmp_ip;
-       int i;
-
-       if (ctdb->ip_tree == NULL) {
-               /* don't know the expected allocation yet, assume remote node
-                  is correct. */
-               return 0;
-       }
-
-       if (ips == NULL) {
-               return 0;
-       }
-
-       for (i=0; i<ips->num; i++) {
-               tmp_ip = trbt_lookuparray32(ctdb->ip_tree, IP_KEYLEN, ip_key(&ips->ip[i].addr));
-               if (tmp_ip == NULL) {
-                       DEBUG(DEBUG_ERR,("Node %u has new or unknown public IP %s\n", pnn, ctdb_addr_to_str(&ips->ip[i].addr)));
-                       return -1;
-               }
-
-               if (tmp_ip->pnn == -1 || ips->ip[i].pnn == -1) {
-                       continue;
-               }
-
-               if (tmp_ip->pnn != ips->ip[i].pnn) {
-                       DEBUG(DEBUG_ERR,
-                             ("Inconsistent IP allocation - node %u thinks %s is held by node %u while it is assigned to node %u\n",
-                              pnn,
-                              ctdb_addr_to_str(&ips->ip[i].addr),
-                              ips->ip[i].pnn, tmp_ip->pnn));
-                       return -1;
-               }
-       }
-
-       return 0;
-}
-
-int update_ip_assignment_tree(struct ctdb_context *ctdb, struct ctdb_public_ip *ip)
-{
-       struct public_ip_list *tmp_ip;
-
-       /* IP tree is never built if DisableIPFailover is set */
-       if (ctdb->tunable.disable_ip_failover != 0) {
-               return 0;
-       }
-
-       if (ctdb->ip_tree == NULL) {
-               DEBUG(DEBUG_ERR,("No ctdb->ip_tree yet. Failed to update ip assignment\n"));
-               return -1;
-       }
-
-       tmp_ip = trbt_lookuparray32(ctdb->ip_tree, IP_KEYLEN, ip_key(&ip->addr));
-       if (tmp_ip == NULL) {
-               DEBUG(DEBUG_ERR,(__location__ " Could not find record for address %s, update ip\n", ctdb_addr_to_str(&ip->addr)));
-               return -1;
-       }
-
-       DEBUG(DEBUG_NOTICE,("Updated ip assignment tree for ip : %s from node %u to node %u\n", ctdb_addr_to_str(&ip->addr), tmp_ip->pnn, ip->pnn));
-       tmp_ip->pnn = ip->pnn;
-
-       return 0;
-}
-
-void clear_ip_assignment_tree(struct ctdb_context *ctdb)
-{
-       TALLOC_FREE(ctdb->ip_tree);
-}
-
 struct ctdb_reloadips_handle {
        struct ctdb_context *ctdb;
        struct ctdb_req_control_old *c;
@@ -3206,7 +2414,7 @@ static int ctdb_reloadips_child(struct ctdb_context *ctdb)
                        struct ctdb_addr_info_old *pub;
                        const char *ifaces = NULL;
                        uint32_t len;
-                       int iface = 0;
+                       struct vnn_interface *iface = NULL;
 
                        DEBUG(DEBUG_NOTICE,
                              ("New IP %s configured, adding it\n",
@@ -3230,12 +2438,12 @@ static int ctdb_reloadips_child(struct ctdb_context *ctdb)
                                first_add = false;
                        }
 
-                       ifaces = vnn->ifaces[0];
-                       iface = 1;
-                       while (vnn->ifaces[iface] != NULL) {
+                       ifaces = vnn->ifaces->iface->name;
+                       iface = vnn->ifaces->next;
+                       while (iface != NULL) {
                                ifaces = talloc_asprintf(vnn, "%s,%s", ifaces,
-                                                        vnn->ifaces[iface]);
-                               iface++;
+                                                        iface->iface->name);
+                               iface = iface->next;
                        }
 
                        len   = strlen(ifaces) + 1;
@@ -3322,10 +2530,9 @@ int32_t ctdb_control_reload_public_ips(struct ctdb_context *ctdb, struct ctdb_re
                signed char res = 0;
 
                close(h->fd[0]);
-               debug_extra = talloc_asprintf(NULL, "reloadips:");
 
                prctl_set_comment("ctdb_reloadips");
-               if (switch_from_server_to_client(ctdb, "reloadips-child") != 0) {
+               if (switch_from_server_to_client(ctdb) != 0) {
                        DEBUG(DEBUG_CRIT,("ERROR: Failed to switch reloadips child into client mode\n"));
                        res = -1;
                } else {