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">
6 <refentrytitle>ctdb</refentrytitle>
7 <manvolnum>1</manvolnum>
12 <refname>ctdb</refname>
13 <refpurpose>clustered tdb database management utility</refpurpose>
18 <command>ctdb [ OPTIONS ] COMMAND ...</command>
22 <command>ctdb</command>
23 <arg choice="opt">-n <node></arg>
24 <arg choice="opt">-Y</arg>
25 <arg choice="opt">-t <timeout></arg>
26 <arg choice="opt">-? --help</arg>
27 <arg choice="opt">--usage</arg>
28 <arg choice="opt">-d --debug=<INTEGER></arg>
29 <arg choice="opt">--socket=<filename></arg>
34 <refsect1><title>DESCRIPTION</title>
36 ctdb is a utility to view and manage a ctdb cluster.
42 <title>OPTIONS</title>
45 <varlistentry><term>-n <node></term>
48 This specifies on which node to execute the command. Default is
49 to run the command on the deamon running on the local host.
54 <varlistentry><term>-Y</term>
57 Produce output in machinereadable form for easier parsing by scripts. Not all commands support this option.
62 <varlistentry><term>-t <timeout></term>
65 How long should ctdb wait for a command to complete before timing out. Default is 3 seconds.
70 <varlistentry><term>-? --help</term>
73 Print some help text to the screen.
78 <varlistentry><term>--usage</term>
81 Print useage information to the screen.
86 <varlistentry><term>-d --debug=<debuglevel></term>
89 Change the debug level for the command. Default is 0.
94 <varlistentry><term>--socket=<filename></term>
97 Specify the socketname to use when connecting to the local ctdb
98 daemon. The default is /tmp/ctdb.socket .
101 You only need to specify this parameter if you run multiple ctdb
102 daemons on the same physical host and thus can not use the default
103 name for the domain socket.
112 <refsect1><title>Administrative Commands</title>
114 These are commands used to monitor and administrate a CTDB cluster.
117 <refsect2><title>status</title>
119 This command shows the current status of the ctdb node.
122 <refsect3><title>node status</title>
124 Node status reflects the current status of the node. There are four possible states:
127 OK - This node is fully functional.
130 DISCONNECTED - This node could not be connected through the network and is currently not parcipitating in the cluster. If there is a public IP address associated with this node it should have been taken over by a different node. No services are running on this node.
133 DISABLED - This node has been administratively disabled. This node is still functional and participates in the CTDB cluster but its IP addresses have been taken over by a different node and no services are currently being hosted.
136 UNHEALTHY - A service provided by this node is malfunctioning and should be investigated. The CTDB daemon itself is operational and participates in the cluster. Its public IP address has been taken over by a different node and no services are currnetly being hosted. All unhealthy nodes should be investigated and require an administrative action to rectify.
139 BANNED - This node failed too many recovery attempts and has been banned from participating in the cluster for a period of RecoveryBanPeriod seconds. Any public IP address has been taken over by other nodes. This node does not provide any services. All banned nodes should be investigated and require an administrative action to rectify. This node does not perticipate in the CTDB cluster but can still be communicated with. I.e. ctdb commands can be sent to it.
143 <refsect3><title>generation</title>
145 The generation id is a number that indicates the current generation
146 of a cluster instance. Each time a cluster goes through a
147 reconfiguration or a recovery its generation id will be changed.
151 <refsect3><title>VNNMAP</title>
153 The list of Virtual Node Numbers. This is a list of all nodes that actively participates in the cluster and that share the workload of hosting the Clustered TDB database records.
154 Only nodes that are parcipitating in the vnnmap can become lmaster or dmaster for a database record.
158 <refsect3><title>Recovery mode</title>
160 This is the current recovery mode of the cluster. There are two possible modes:
163 NORMAL - The cluster is fully operational.
166 RECOVERY - The cluster databases have all been frozen, pausing all services while the cluster awaits a recovery process to complete. A recovery process should finish within seconds. If a cluster is stuck in the RECOVERY state this would indicate a cluster malfunction which needs to be investigated.
170 <refsect3><title>Recovery master</title>
172 This is the cluster node that is currently designated as the recovery master. This node is responsible of monitoring the consistency of the cluster and to perform the actual recovery process when reqired.
179 <para>Example output:</para>
180 <screen format="linespecific">
182 vnn:0 11.1.2.200 OK (THIS NODE)
186 Generation:1362079228
192 Recovery mode:NORMAL (0)
197 <refsect2><title>ping</title>
199 This command will "ping" all CTDB daemons in the cluster to verify that they are processing commands correctly.
207 <screen format="linespecific">
208 response from 0 time=0.000054 sec (3 clients)
209 response from 1 time=0.000144 sec (2 clients)
210 response from 2 time=0.000105 sec (2 clients)
211 response from 3 time=0.000114 sec (2 clients)
215 <refsect2><title>ip</title>
217 This command will display the list of public addresses that are provided by the cluster and which physical node is currently serving this ip.
225 <screen format="linespecific">
234 <refsect2><title>getvar <name></title>
236 Get the runtime value of a tuneable variable.
239 Example: ctdb getvar MaxRedirectCount
244 <screen format="linespecific">
249 <refsect2><title>setvar <name> <value></title>
251 Set the runtime value of a tuneable variable.
254 Example: ctdb setvar MaxRedirectCount 5
258 <refsect2><title>listvars</title>
260 List all tuneable variables.
263 Example: ctdb listvars
268 <screen format="linespecific">
273 KeepaliveInterval = 2
281 EventScriptTimeout = 20
282 RecoveryGracePeriod = 60
283 RecoveryBanPeriod = 300
287 <refsect2><title>statistics</title>
289 Collect statistics from the CTDB daemon about how many calls it has served.
292 Example: ctdb statistics
297 <screen format="linespecific">
302 client_packets_sent 360489
303 client_packets_recv 360466
304 node_packets_sent 480931
305 node_packets_recv 240120
306 keepalive_packets_sent 4
307 keepalive_packets_recv 3
328 pending_lockwait_calls 0
331 max_call_latency 4.948321 sec
332 max_lockwait_latency 0.000000 sec
336 <refsect2><title>statisticsreset</title>
338 This command is used to clear all statistics counters in a node.
341 Example: ctdb statisticsreset
345 <refsect2><title>getdebug</title>
347 Get the current debug level for the node. the debug level controls what information is written to the log file.
351 <refsect2><title>setdebug <debuglevel></title>
353 Set the debug level of a node. This is a number between 0 and 9 and controls what information will be written to the logfile.
357 <refsect2><title>getpid</title>
359 This command will return the process id of the ctdb daemon.
363 <refsect2><title>disable</title>
365 This command is used to administratively disable a node in the cluster.
366 A disabled node will still participate in the cluster and host
367 clustered TDB records but its public ip address has been taken over by
368 a different node and it no longer hosts any services.
372 <refsect2><title>enable</title>
374 Re-enable a node that has been administratively disabled.
378 <refsect2><title>ban <bantime|0></title>
380 Administratively ban a node for bantime seconds. A bantime of 0 means that the node should be permanently banned.
383 A banned node does not participate in the cluster and does not host any records for the clustered TDB. Its ip address has been taken over by an other node and no services are hosted.
386 Nodes are automatically banned if they are the cause of too many
391 <refsect2><title>unban</title>
393 This command is used to unban a node that has either been
394 administratively banned using the ban command or has been automatically
395 banned by the recovery daemon.
399 <refsect2><title>shutdown</title>
401 This command will shutdown a specific CTDB daemon.
405 <refsect2><title>recover</title>
407 This command will trigger the recovery daemon to do a cluster
412 <refsect2><title>killtcp <srcip:port> <dstip:port></title>
414 This command will kill the specified TCP connection by issuing a
415 TCP RST to the srcip:port endpoint.
419 <refsect2><title>tickle <srcip:port> <dstip:port></title>
421 This command will will send a TCP tickle to the source host for the
422 specified TCP connection.
423 A TCP tickle is a TCP ACK packet with an invalid sequence and
424 acknowledge number and will when received by the source host result
425 in it sending an immediate correct ACK back to the other end.
428 TCP tickles are useful to "tickle" clients after a IP failover has
429 occured since this will make the client immediately recognize the
430 TCP connection has been disrupted and that the client will need
431 to reestablish. This greatly speeds up the time it takes for a client
432 to detect and reestablish after an IP failover in the ctdb cluster.
439 <refsect1><title>Debugging Commands</title>
441 These commands are primarily used for CTDB development and testing and
442 should not be used for normal administration.
444 <refsect2><title>process-exists <pid></title>
446 This command checks if a specific process exists on the CTDB host. This is mainly used by Samba to check if remote instances of samba are still running or not.
450 <refsect2><title>getdbmap</title>
452 This command lists all clustered TDB databases that the CTDB daemon has attahced to.
455 Example: ctdb getdbmap
460 <screen format="linespecific">
461 Number of databases:4
462 dbid:0x42fe72c5 name:locking.tdb path:/var/ctdb/locking.tdb.0
463 dbid:0x1421fb78 name:brlock.tdb path:/var/ctdb/brlock.tdb.0
464 dbid:0x17055d90 name:connections.tdb path:/var/ctdb/connections.tdb.0
465 dbid:0xc0bdde6a name:sessionid.tdb path:/var/ctdb/sessionid.tdb.0
469 <refsect2><title>catdb <dbname></title>
471 This command will dump a clustered TDB database to the screen. This is a debugging command.
475 <refsect2><title>getmonmode</title>
477 This command returns the monutoring mode of a node. The monitoring mode is either ACTIVE or DISABLED. Normally a node will continously monitor that all other nodes that are expected are in fact connected and that they respond to commands.
480 ACTIVE - This is the normal mode. The node is actively monitoring all other nodes, both that the transport is connected and also that the node responds to commands. If a node becomes unavailable, it will be marked as DISCONNECTED and a recovery is initiated to restore the cluster.
483 DISABLED - This node is not monitoring that other nodes are available. In this mode a node failure will not be detected and no recovery will be performed. This mode is useful when for debugging purposes one wants to attach GDB to a ctdb process but wants to prevent the rest of the cluster from marking this node as DISCONNECTED and do a recovery.
488 <refsect2><title>setmonmode <0|1></title>
490 This command can be used to explicitely disable/enable monitoring mode on a node. The main purpose is if one wants to attach GDB to a running ctdb daemon but wants to prevent the other nodes from marking it as DISCONNECTED and issuing a recovery. To do this, set monitoring mode to 0 on all nodes before attaching with GDB. Remember to set monitoring mode back to 1 afterwards.
494 <refsect2><title>attach <dbname></title>
496 This is a debugging command. This command will make the CTDB daemon create a new CTDB database and attach to it.
500 <refsect2><title>dumpmemory</title>
502 This is a debugging command. This command will make the ctdb daemon to write a fill memory allocation map to the log file.
506 <refsect2><title>freeze</title>
508 This command will lock all the local TDB databases causing clients
509 that are accessing these TDBs such as samba3 to block until the
510 databases are thawed.
513 This is primarily used by the recovery daemon to stop all samba
514 daemons from accessing any databases while the database is recovered
519 <refsect2><title>thaw</title>
521 Thaw a previously frozen node.
528 <refsect1><title>SEE ALSO</title>
531 <ulink url="http://ctdb.samba.org/"/>
534 <refsect1><title>COPYRIGHT/LICENSE</title>
536 Copyright (C) Andrew Tridgell 2007
537 Copyright (C) Ronnie sahlberg 2007
539 This program is free software; you can redistribute it and/or modify
540 it under the terms of the GNU General Public License as published by
541 the Free Software Foundation; either version 3 of the License, or (at
542 your option) any later version.
544 This program is distributed in the hope that it will be useful, but
545 WITHOUT ANY WARRANTY; without even the implied warranty of
546 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
547 General Public License for more details.
549 You should have received a copy of the GNU General Public License
550 along with this program; if not, see http://www.gnu.org/licenses/.