1 <?xml version="1.0" encoding="iso-8859-1"?>
2 <!DOCTYPE refentry PUBLIC "-//Samba-Team//DTD DocBook V4.2-Based Variant V1.0//EN" "http://www.samba.org/samba/DTD/samba-doc">
3 <refentry id="ctdbd.1">
6 <refentrytitle>ctdbd</refentrytitle>
7 <manvolnum>1</manvolnum>
12 <refname>ctdbd</refname>
13 <refpurpose>The CTDB cluster daemon</refpurpose>
18 <command>ctdbd</command>
22 <command>ctdbd</command>
23 <arg choice="opt">-? --help</arg>
24 <arg choice="opt">-d --debug=<INTEGER></arg>
25 <arg choice="req">--dbdir=<directory></arg>
26 <arg choice="req">--dbdir-persistent=<directory></arg>
27 <arg choice="opt">--event-script-dir=<directory></arg>
28 <arg choice="opt">-i --interactive</arg>
29 <arg choice="opt">--listen=<address></arg>
30 <arg choice="opt">--logfile=<filename></arg>
31 <arg choice="opt">--lvs</arg>
32 <arg choice="req">--nlist=<filename></arg>
33 <arg choice="opt">--no-lmaster</arg>
34 <arg choice="opt">--no-recmaster</arg>
35 <arg choice="opt">--nosetsched</arg>
36 <arg choice="opt">--public-addresses=<filename></arg>
37 <arg choice="opt">--public-interface=<interface></arg>
38 <arg choice="req">--reclock=<filename></arg>
39 <arg choice="opt">--single-public-ip=<address></arg>
40 <arg choice="opt">--socket=<filename></arg>
41 <arg choice="opt">--start-as-disabled</arg>
42 <arg choice="opt">--syslog</arg>
43 <arg choice="opt">--torture</arg>
44 <arg choice="opt">--transport=<STRING></arg>
45 <arg choice="opt">--usage</arg>
50 <refsect1><title>DESCRIPTION</title>
52 ctdbd is the main ctdb daemon.
55 ctdbd provides a clustered version of the TDB database with automatic rebuild/recovery of the databases upon nodefailures.
58 Combined with a cluster filesystem ctdbd provides a full HA environment for services such as clustered Samba and NFS as well as other services.
61 ctdbd provides monitoring of all nodes in the cluster and automatically reconfigures the cluster and recovers upon node failures.
64 ctdbd is the main component in clustered Samba that provides a high-availability load-sharing CIFS server cluster.
70 <title>OPTIONS</title>
73 <varlistentry><term>-? --help</term>
76 Print some help text to the screen.
81 <varlistentry><term>-d --debug=<DEBUGLEVEL></term>
84 This option sets the debuglevel on the ctdbd daemon which controls what will be written to the logfile. The default is 0 which will only log important events and errors. A larger number will provide additional logging.
89 <varlistentry><term>--dbdir=<directory></term>
92 This is the directory on local storage where ctdbd keeps the local
93 copy of the TDB databases. This directory is local for each node and should not be stored on the shared cluster filesystem.
96 This directory would usually be /var/ctdb .
101 <varlistentry><term>--dbdir-persistent=<directory></term>
104 This is the directory on local storage where ctdbd keeps the local
105 copy of the persistent TDB databases. This directory is local for each node and should not be stored on the shared cluster filesystem.
108 This directory would usually be /etc/ctdb/persistent .
113 <varlistentry><term>--event-script-dir=<directory></term>
116 This option is used to specify the directory where the CTDB event
120 This will normally be /etc/ctdb/events.d which is part of the ctdb distribution.
125 <varlistentry><term>-i --interactive</term>
128 By default ctdbd will detach itself from the shell and run in
129 the background as a daemon. This option makes ctdbd to start in interactive mode.
134 <varlistentry><term>--listen=<address></term>
137 This specifies which ip address ctdb will bind to. By default ctdbd will bind to the first address it finds in the /etc/ctdb/nodes file and which is also present on the local system in which case you do not need to provide this option.
140 This option is only required when you want to run multiple ctdbd daemons/nodes on the same physical host in which case there would be multiple entries in /etc/ctdb/nodes what would match a local interface.
145 <varlistentry><term>--logfile=<filename></term>
148 This is the file where ctdbd will write its log. This is usually /var/log/log.ctdb .
153 <varlistentry><term>--lvs</term>
156 This option is used to activate the LVS capability on a CTDB node.
157 Please see the LVS section.
162 <varlistentry><term>--nlist=<filename></term>
165 This file contains a list of the private ip addresses of every node in the cluster. There is one line/ip address for each node. This file must be the same for all nodes in the cluster.
168 This file is usually /etc/ctdb/nodes .
173 <varlistentry><term>--no-lmaster</term>
176 This argument specifies that this node can NOT become an lmaster
177 for records in the database. This means that it will never show up
178 in the vnnmap. This feature is primarily used for making a cluster
179 span across a WAN link and use CTDB as a WAN-accelerator.
182 Please see the "remote cluster nodes" section for more information.
187 <varlistentry><term>--no-recmaster</term>
190 This argument specifies that this node can NOT become a recmaster
191 for the database. This feature is primarily used for making a cluster
192 span across a WAN link and use CTDB as a WAN-accelerator.
195 Please see the "remote cluster nodes" section for more information.
200 <varlistentry><term>--nosetsched</term>
203 This is a ctdbd debugging option. this option is only used when
207 Normally ctdb will change its scheduler to run as a real-time
208 process. This is the default mode for a normal ctdbd operation
209 to gurarantee that ctdbd always gets the cpu cycles that it needs.
212 This option is used to tell ctdbd to NOT run as a real-time process
213 and instead run ctdbd as a normal userspace process.
214 This is useful for debugging and when you want to run ctdbd under
215 valgrind or gdb. (You dont want to attach valgrind or gdb to a
221 <varlistentry><term>--public_addresses=<filename></term>
224 When used with IP takeover this specifies a file containing the public ip addresses to use on the cluster. This file contains a list of ip addresses netmasks and interfaces. When ctdb is operational it will distribute these public ip addresses evenly across the available nodes.
227 This is usually the file /etc/ctdb/public_addresses
232 <varlistentry><term>--public-interface=<interface></term>
235 This option tells ctdb which interface to attach public-addresses
236 to and also where to attach the single-public-ip when used.
239 This is only required when using public ip addresses and only when
240 you dont specify the interface explicitly in /etc/ctdb/public_addresses or when you are using --single-public-ip.
243 If you omit this argument when using public addresses or single public ip, ctdb will not be able to send out Gratious ARPs correctly or be able to kill tcp connections correctly which will lead to application failures.
248 <varlistentry><term>--reclock=<filename></term>
251 This is the name of the lock file stored of the shared cluster filesystem that ctdbd uses to arbitrate which node has the role of recovery-master.
252 This file must be stored on shared storage.
257 <varlistentry><term>--socket=<filename></term>
260 This specifies the name of the domain socket that ctdbd will create. This socket is used for local clients to attach to and communicate with the ctdbd daemon.
263 The default is /tmp/ctdb.socket . You only need to use this option if you plan to run multiple ctdbd daemons on the same physical host.
268 <varlistentry><term>--start-as-disabled</term>
271 This makes the ctdb daemon to be DISABLED when it starts up.
274 As it is DISABLED it will not get any of the public ip addresses
275 allocated to it, and thus this allow you to start ctdb on a node
276 without causing any ip address to failover from other nodes onto
280 When used, the administrator must keep track of when nodes start and
281 manually enable them again using the "ctdb enable" command, or else
282 the node will not host any services.
285 A node that is DISABLED will not host any services and will not be
286 reachable/used by any clients.
291 <varlistentry><term>--syslog</term>
294 Send all log messages to syslog instead of to the ctdb logfile.
299 <varlistentry><term>--torture</term>
302 This option is only used for development and testing of ctdbd. It adds artificial errors and failures to the common codepaths in ctdbd to verify that ctdbd can recover correctly for failures.
305 You do NOT want to use this option unless you are developing and testing new functionality in ctdbd.
310 <varlistentry><term>--transport=<STRING></term>
313 This option specifies which transport to use for ctdbd internode communications. The default is "tcp".
316 Currently only "tcp" is supported but "infiniband" might be
317 implemented in the future.
322 <varlistentry><term>--usage</term>
325 Print useage information to the screen.
334 <refsect1><title>Private vs Public addresses</title>
336 When used for ip takeover in a HA environment, each node in a ctdb
337 cluster has multiple ip addresses assigned to it. One private and one or more public.
340 <refsect2><title>Private address</title>
342 This is the physical ip address of the node which is configured in
343 linux and attached to a physical interface. This address uniquely
344 identifies a physical node in the cluster and is the ip addresses
345 that ctdbd will use to communicate with the ctdbd daemons on the
346 other nodes in the cluster.
349 The private addresses are configured in /etc/ctdb/nodes
350 (unless the --nlist option is used) and contain one line for each
351 node in the cluster. Each line contains the private ip address for one
352 node in the cluster. This file must be the same on all nodes in the
356 Since the private addresses are only available to the network when the
357 corresponding node is up and running you should not use these addresses
358 for clients to connect to services provided by the cluster. Instead
359 client applications should only attach to the public addresses since
360 these are guaranteed to always be available.
363 When using ip takeover, it is strongly recommended that the private
364 addresses are configured on a private network physically separated
365 from the rest of the network and that this private network is dedicated
368 Example /etc/ctdb/nodes for a four node cluster:
369 <screen format="linespecific">
376 <refsect2><title>Public address</title>
378 A public address on the other hand is not attached to an interface.
379 This address is managed by ctdbd itself and is attached/detached to
380 a physical node at runtime.
383 The ctdb cluster will assign/reassign these public addresses across the
384 available healthy nodes in the cluster. When one node fails, its public address
385 will be migrated to and taken over by a different node in the cluster
386 to ensure that all public addresses are always available to clients as
387 long as there are still nodes available capable of hosting this address.
390 These addresses are not physically attached to a specific node.
391 The 'ctdb ip' command can be used to view the current assignment of
392 public addresses and which physical node is currently serving it.
395 On each node this file contains a list of the public addresses that
396 this node is capable of hosting.
397 The list also contain the netmask and the
398 interface where this address should be attached for the case where you
399 may want to serve data out through multiple different interfaces.
401 Example /etc/ctdb/public_addresses for a node that can host 4 public addresses:
402 <screen format="linespecific">
410 In most cases this file would be the same on all nodes in a cluster but
411 there are exceptions when one may want to use different files
414 Example: 4 nodes partitioned into two subgroups :
415 <screen format="linespecific">
416 Node 0:/etc/ctdb/public_addresses
420 Node 1:/etc/ctdb/public_addresses
424 Node 2:/etc/ctdb/public_addresses
428 Node 3:/etc/ctdb/public_addresses
433 In this example nodes 0 and 1 host two public addresses on the
434 10.1.1.x network while nodes 2 and 3 host two public addresses for the
438 Ip address 10.1.1.1 can be hosted by either of nodes 0 or 1 and will be
439 available to clients as long as at least one of these two nodes are
441 If both nodes 0 and node 1 become unavailable 10.1.1.1 also becomes
442 unavailable. 10.1.1.1 can not be failed over to node 2 or node 3 since
443 these nodes do not have this ip address listed in their public
450 <refsect1><title>Node status</title>
452 The current status of each node in the cluster can be viewed by the
453 'ctdb status' command.
456 There are five possible states for a node.
460 OK - This node is fully functional.
464 DISCONNECTED - This node could not be connected through the network
465 and is currently not particpating in the cluster. If there is a
466 public IP address associated with this node it should have been taken
467 over by a different node. No services are running on this node.
471 DISABLED - This node has been administratively disabled. This node is
472 still functional and participates in the CTDB cluster but its IP
473 addresses have been taken over by a different node and no services are
474 currently being hosted.
478 UNHEALTHY - A service provided by this node is malfunctioning and should
479 be investigated. The CTDB daemon itself is operational and participates
480 in the cluster. Its public IP address has been taken over by a different
481 node and no services are currently being hosted. All unhealthy nodes
482 should be investigated and require an administrative action to rectify.
486 BANNED - This node failed too many recovery attempts and has been banned
487 from participating in the cluster for a period of RecoveryBanPeriod
488 seconds. Any public IP address has been taken over by other nodes. This
489 node does not provide any services. All banned nodes should be
490 investigated and require an administrative action to rectify. This node
491 does not perticipate in the CTDB cluster but can still be communicated
492 with. I.e. ctdb commands can be sent to it.
497 <title>PUBLIC TUNABLES</title>
499 These are the public tuneables that can be used to control how ctdb behaves.
502 <refsect2><title>KeepaliveInterval</title>
503 <para>Default: 1</para>
505 How often should the nodes send keepalives to eachother.
508 <refsect2><title>KeepaliveLimit</title>
509 <para>Default: 5</para>
511 After how many keepalive intervals without any traffic should a node
512 wait until marking the peer as DISCONNECTED.
515 <refsect2><title>MonitorInterval</title>
516 <para>Default: 15</para>
518 How often should ctdb run the event scripts to check for a nodes health.
521 <refsect2><title>TickleUpdateInterval</title>
522 <para>Default: 20</para>
524 How often will ctdb record and store the "tickle" information used to
525 kickstart stalled tcp connections after a recovery.
528 <refsect2><title>EventScriptTimeout</title>
529 <para>Default: 20</para>
531 How long should ctdb let an event script run before aborting it and
532 marking the node unhealthy.
535 <refsect2><title>RecoveryBanPeriod</title>
536 <para>Default: 300</para>
538 If a node becomes banned causing repetitive recovery failures. The node will
539 eventually become banned from the cluster.
540 This controls how long the culprit node will be banned from the cluster
541 before it is allowed to try to join the cluster again.
542 Dont set to small. A node gets banned for a reason and it is usually due
543 to real problems with the node.
546 <refsect2><title>DatabaseHashSize</title>
547 <para>Default: 100000</para>
549 Size of the hash chains for the local store of the tdbs that ctdb manages.
552 <refsect2><title>RerecoveryTimeout</title>
553 <para>Default: 10</para>
555 Once a recovery has completed, no additional recoveries are permitted until this timeout has expired.
558 <refsect2><title>EnableBans</title>
559 <para>Default: 1</para>
561 When set to 0, this disables BANNING completely in the cluster and thus nodes can not get banned, even it they break. Dont set to 0.
564 <refsect2><title>DeterministicIPs</title>
565 <para>Default: 1</para>
567 When enabled, this tunable makes ctdb try to keep public IP addresses locked to specific nodes as far as possible. This makes it easier for debugging since you can know that as long as all nodes are healthy public IP X will always be hosted by node Y.
570 The cost of using deterministic IP address assignment is that it disables part of the logic where ctdb tries to reduce the number of public IP assignment changes in the cluster. This tunable may increase the number of IP failover/failbacks that are performed on the cluster by a small margin.
573 <refsect2><title>DisableWhenUnhealthy</title>
574 <para>Default: 0</para>
576 When set, As soon as a node becomes unhealthy, that node will also automatically become permanently DISABLED. Once a node is DISABLED, the only way to make it participate in the cluster again and host services is by manually enabling the node again using 'ctdb enable'.
579 This disables parts of the resilience and robustness of the cluster and should ONLY be used when the system administrator is actively monitoring the cluster, so that nodes can be enabled again.
582 <refsect2><title>NoIPFailback</title>
583 <para>Default: 0</para>
585 When set to 1, ctdb will not perform failback of IP addresses when a node becomes healthy. Ctdb WILL perform failover of public IP addresses when a node becomes UNHEALTHY, but when the node becomes HEALTHY again, ctdb will not fail the addresses back.
588 Use with caution! Normally when a node becomes available to the cluster
589 ctdb will try to reassign public IP addresses onto the new node as a way to distribute the workload evenly across the clusternode. Ctdb tries to make sure that all running nodes have approximately the same number of public addresses it hosts.
592 When you enable this tunable, CTDB will no longer attempt to rebalance the cluster by failing IP addresses back to the new nodes. An unbalanced cluster will therefore remain unbalanced until there is manual intervention from the administrator. When this parameter is set, you can manually fail public IP addresses over to the new node(s) using the 'ctdb moveip' command.
597 <refsect1><title>LVS</title>
599 LVS is a mode where CTDB presents one single IP address for the entire
600 cluster. This is an alternative to using public IP addresses and round-robin
601 DNS to loadbalance clients across the cluster.
605 This is similar to using a layer-4 loadbalancing switch but with some restrictions.
609 In this mode the cluster select a set of nodes in the cluster and loadbalance
610 all client access to the LVS address across this set of nodes. This set of nodes are all LVS capable nodes that are HEALTHY, or if no HEALTHY nodes exists
611 all LVS capable nodes regardless of health status.
612 LVS will however never loadbalance traffic to nodes that are BANNED,
613 DISABLED or DISCONNECTED. The "ctdb lvs" command is used to show
614 which nodes are currently load-balanced across.
618 One of the these nodes are elected as the LVSMASTER. This node receives all
619 traffic from clients coming in to the LVS address and multiplexes it
620 across the internal network to one of the nodes that LVS is using.
621 When responding to the client, that node will send the data back
622 directly to the client, bypassing the LVSMASTER node.
623 The command "ctdb lvsmaster" will show which node is the current
628 The path used for a client i/o is thus :
629 <screen format="linespecific">
630 (1) Client sends request packet to LVSMASTER
631 (2) LVSMASTER passes the request on to one node across the internal network.
632 (3) Selected node processes the request.
633 (4) Node responds back to client.
638 This means that all incoming traffic to the cluster will pass through
639 one physical node, which limits scalability. You can send more data to the
640 LVS address that one physical node can multiplex. This means that you
641 should not use LVS if your I/O pattern is write-intensive since you will be
642 limited in the available network bandwidth that node can handle.
643 LVS does work wery well for read-intensive workloads where only smallish
644 READ requests are going through the LVSMASTER bottleneck and the majority
645 of the traffic volume (the data in the read replies) goes straight from
646 the processing node back to the clients. For read-intensive i/o patterns you can acheive very high throughput rates in this mode.
650 Note: you can use LVS and public addresses at the same time.
653 <refsect2><title>Configuration</title>
655 To activate LVS on a CTDB node you must specify CTDB_PUBLIC_INTERFACE and
656 CTDB_LVS_PUBLIC_ADDRESS in /etc/sysconfig/ctdb.
660 You must also specify the "--lvs" command line argument to ctdbd to activete LVS as a capability of the node. This should be done automatically for you by the /etc/init.d/ctdb script.
665 <screen format="linespecific">
666 CTDB_PUBLIC_INTERFACE=eth0
667 CTDB_LVS_PUBLIC_IP=10.0.0.237
674 If you use LVS, you must still have a real/permanent address configured
675 for the public interface on each node. This address must be routable
676 and the cluster nodes must be configured so that all traffic back to client
677 hosts are routed through this interface. This is also required in order
678 to allow samba/winbind on the node to talk to the domain controller.
679 (we can not use the lvs IP address to initiate outgoing traffic)
682 I.e. make sure that you can "ping" both the domain controller and also
683 all of the clients from the node BEFORE you enable LVS. Also make sure
684 that when you ping these hosts that the traffic is routed out through the
690 <refsect1><title>REMOTE CLUSTER NODES</title>
692 It is possible to have a CTDB cluster that spans across a WAN link.
693 For example where you have a CTDB cluster in your datacentre but you also
694 want to have one additional CTDB node located at a remote branch site.
695 This is similar to how a WAN accelerator works but with the difference
696 that while a WAN-accelerator often acts as a Proxy or a MitM, in
697 the ctdb remote cluster node configuration the Samba instance at the remote site
698 IS the genuine server, not a proxy and not a MitM, and thus provides 100%
699 correct CIFS semantics to clients.
703 See the cluster as one single multihomed samba server where one of
704 the NICs (the remote node) is very far away.
708 NOTE: This does require that the cluster filesystem you use can cope
709 with WAN-link latencies. Not all cluster filesystems can handle
710 WAN-link latencies! Whether this will provide very good WAN-accelerator
711 performance or it will perform very poorly depends entirely
712 on how optimized your cluster filesystem is in handling high latency
713 for data and metadata operations.
717 To activate a node as being a remote cluster node you need to set
718 the following two parameters in /etc/sysconfig/ctdb for the remote node:
719 <screen format="linespecific">
720 CTDB_CAPABILITY_LMASTER=no
721 CTDB_CAPABILITY_RECMASTER=no
726 Verify with the command "ctdb getcapabilities" that that node no longer
727 has the recmaster or the lmaster capabilities.
733 <refsect1><title>NAT-GW</title>
735 Sometimes it is desireable to run services on the CTDB node which will
736 need to originate outgoing traffic to external servers. This might
737 be contacting NIS servers, LDAP servers etc. etc.
740 This can sometimes be problematic since there are situations when a
741 node does not have any public ip addresses assigned. This could
742 be due to the nobe just being started up and no addresses have been
743 assigned yet or it could be that the node is UNHEALTHY in which
744 case all public addresses have been migrated off.
747 If then the service status of CTDB depends on such services being
748 able to always being able to originate traffic to external resources
749 this becomes extra troublesome. The node might be UNHEALTHY because
750 the service can not be reached, and the service can not be reached
751 because the node is UNHEALTHY.
754 There are two ways to solve this problem. The first is by assigning a
755 static ip address for one public interface on every node which will allow
756 every node to be able to route traffic to the public network even
757 if there are no public addresses assigned to the node.
758 This is the simplest way but it uses up a lot of ip addresses since you
759 have to assign both static and also public addresses to each node.
761 <refsect2><title>NAT-GW</title>
763 A second way is to use the built in NAT-GW feature in CTDB.
764 With NAT-GW you assign one public NATGW address for each natgw group.
765 Each NATGW group is a set of nodes in the cluster that shares the same
766 NATGW address to talk to the outside world. Normally there would only be
767 one NATGW group spanning the entire cluster, but in situations where one
768 ctdb cluster spans multiple physical sites it is useful to have one
769 NATGW group for each of the two sites.
772 There can be multiple NATGW groups in one cluster but each node can only
773 be member of one NATGW group.
776 In each NATGW group, one of the nodes is designated the NAT Gateway
777 through which all traffic that is originated by nodes in this group
778 will be routed through if a public addresses are not available.
782 <refsect2><title>Configuration</title>
784 NAT-GW is configured in /etc/sysconfigctdb by setting the following
787 <screen format="linespecific">
788 # NAT-GW configuration
789 # Some services running on nthe CTDB node may need to originate traffic to
790 # remote servers before the node is assigned any IP addresses,
791 # This is problematic since before the node has public addresses the node might
792 # not be able to route traffic to the public networks.
793 # One solution is to have static public addresses assigned with routing
794 # in addition to the public address interfaces, thus guaranteeing that
795 # a node always can route traffic to the external network.
796 # This is the most simple solution but it uses up a large number of
797 # additional ip addresses.
799 # A more complex solution is NAT-GW.
800 # In this mode we only need one additional ip address for the cluster from
801 # the exsternal public network.
802 # One of the nodes in the cluster is elected to be hosting this ip address
803 # so it can reach the external services. This node is also configured
804 # to use NAT MASQUERADING for all traffic from the internal private network
805 # to the external network. This node is the NAT-GW node.
807 # All other nodes are set up with a default rote with a metric of 10 to point
808 # to the nat-gw node.
810 # The effect of this is that only when a node does not have a public address
811 # and thus no proper routes to the external world it will instead
812 # route all packets through the nat-gw node.
814 # CTDB_NATGW_NODES is the list of nodes that belong to this natgw group.
815 # You can have multiple natgw groups in one cluster but each node
816 # can only belong to one single natgw group.
818 # CTDB_NATGW_PUBLIC_IP=10.0.0.227/24
819 # CTDB_NATGW_PUBLIC_IFACE=eth0
820 # CTDB_NATGW_DEFAULT_GATEWAY=10.0.0.1
821 # CTDB_NATGW_PRIVATE_NETWORK=10.1.1.0/24
822 # CTDB_NATGW_NODES=/etc/ctdb/natgw_nodes
826 <refsect2><title>CTDB_NATGW_PUBLIC_IP</title>
828 This is an ip address in the public network that is used for all outgoing
829 traffic when the public addresses are not assigned.
830 This address will be assigned to one of the nodes in the cluster which
831 will masquerade all traffic for the other nodes.
834 Format of this parameter is IPADDRESS/NETMASK
838 <refsect2><title>CTDB_NATGW_PUBLIC_IFACE</title>
840 This is the physical interface where the CTDB_NATGW_PUBLIC_IP will be
841 assigned to. This should be an interface connected to the public network.
844 Format of this parameter is INTERFACE
848 <refsect2><title>CTDB_NATGW_DEFAULT_GATEWAY</title>
850 This is the default gateway to use on the node that is elected to host
851 the CTDB_NATGW_PUBLIC_IP. This is the default gateway on the public network.
854 Format of this parameter is IPADDRESS
858 <refsect2><title>CTDB_NATGW_PRIVATE_NETWORK</title>
860 This is the network/netmask used for the interal private network.
863 Format of this parameter is IPADDRESS/NETMASK
867 <refsect2><title>CTDB_NATGW_NODES</title>
869 This is the list of all nodes that belong to the same NATGW group
870 as this node. The default is /etc/ctdb/natgw_nodes.
874 <refsect2><title>Operation</title>
876 When the NAT-GW fiunctionality is used, one of the nodes is elected
877 to act as a NAT router for all the other nodes in the group when
878 they need to originate traffic to the external public network.
881 The NAT-GW node is assigned the CTDB_NATGW_PUBLIC_IP to the designated
882 interface and the provided default route. The NAT-GW is configured
883 to act as a router and to masquerade all traffic it receives from the
884 internal private network and which is destined to the external network(s).
887 All other nodes in the group are configured with a default route of
888 metric 10 pointing to the designated NAT GW node.
891 This is implemented in the 11.natgw eventscript. Please see the
892 eventscript for further information.
901 <refsect1><title>ClamAV Daemon</title>
903 CTDB has support to manage the popular anti-virus daemon ClamAV.
904 This support is implemented through the
905 eventscript : /etc/ctdb/events.d/31.clamd.
908 <refsect2><title>Configuration</title>
910 Start by configuring CLAMAV normally and test that it works. Once this is
911 done, copy the configuration files over to all the nodes so that all nodes
912 share identical CLAMAV configurations.
913 Once this is done you can proceed with the intructions below to activate
914 CTDB support for CLAMAV.
918 First, to activate CLAMAV support in CTDB, edit /etc/sysconfig/ctdb and add the two lines :
920 <screen format="linespecific">
921 CTDB_MANAGES_CLAMD=yes
922 CTDB_CLAMD_SOCKET="/path/to/clamd.socket"
926 Second, activate the eventscript by making it executable:
928 <screen format="linespecific">
929 chmod +x /etc/ctdb/events.d/31.clamd
933 Third, CTDB will now be starting and stopping this service accordingly,
934 so make sure that the system is not configured to start/stop this service
936 On RedHat systems you can disable the system starting/stopping CLAMAV automatically by running :
937 <screen format="linespecific">
944 Once you have restarted CTDBD, use
945 <screen format="linespecific">
948 and verify that the 31.clamd eventscript is listed and that it was executed successfully.
957 <refsect1><title>SEE ALSO</title>
960 <ulink url="http://ctdb.samba.org/"/>
964 <refsect1><title>COPYRIGHT/LICENSE</title>
966 Copyright (C) Andrew Tridgell 2007
967 Copyright (C) Ronnie sahlberg 2007
969 This program is free software; you can redistribute it and/or modify
970 it under the terms of the GNU General Public License as published by
971 the Free Software Foundation; either version 3 of the License, or (at
972 your option) any later version.
974 This program is distributed in the hope that it will be useful, but
975 WITHOUT ANY WARRANTY; without even the implied warranty of
976 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
977 General Public License for more details.
979 You should have received a copy of the GNU General Public License
980 along with this program; if not, see http://www.gnu.org/licenses/.