1 <html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>ctdb</title><meta name="generator" content="DocBook XSL Stylesheets V1.73.2"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en"><a name="ctdb.1"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>ctdb — clustered tdb database management utility</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="cmdsynopsis"><p><code class="command">ctdb [ OPTIONS ] COMMAND ...</code> </p></div><div class="cmdsynopsis"><p><code class="command">ctdb</code> [-n <node>] [-Y] [-t <timeout>] [-T <timelimit>] [-? --help] [--usage] [-d --debug=<INTEGER>] [--socket=<filename>]</p></div></div><div class="refsect1" lang="en"><a name="id2478395"></a><h2>DESCRIPTION</h2><p>
2 ctdb is a utility to view and manage a ctdb cluster.
3 </p></div><div class="refsect1" lang="en"><a name="id2478405"></a><h2>OPTIONS</h2><div class="variablelist"><dl><dt><span class="term">-n <pnn></span></dt><dd><p>
4 This specifies the physical node number on which to execute the
5 command. Default is to run the command on the deamon running on
8 The physical node number is an integer that describes the node in the
9 cluster. The first node has physical node number 0.
10 </p></dd><dt><span class="term">-Y</span></dt><dd><p>
11 Produce output in machine readable form for easier parsing by scripts. Not all commands support this option.
12 </p></dd><dt><span class="term">-t <timeout></span></dt><dd><p>
13 How long should ctdb wait for the local ctdb daemon to respond to a command before timing out. Default is 3 seconds.
14 </p></dd><dt><span class="term">-T <timelimit></span></dt><dd><p>
15 A limit on how long the ctdb command will run for before it will
16 be aborted. When this timelimit has been exceeded the ctdb command will
18 </p></dd><dt><span class="term">-? --help</span></dt><dd><p>
19 Print some help text to the screen.
20 </p></dd><dt><span class="term">--usage</span></dt><dd><p>
21 Print useage information to the screen.
22 </p></dd><dt><span class="term">-d --debug=<debuglevel></span></dt><dd><p>
23 Change the debug level for the command. Default is 0.
24 </p></dd><dt><span class="term">--socket=<filename></span></dt><dd><p>
25 Specify the socketname to use when connecting to the local ctdb
26 daemon. The default is /tmp/ctdb.socket .
28 You only need to specify this parameter if you run multiple ctdb
29 daemons on the same physical host and thus can not use the default
30 name for the domain socket.
31 </p></dd></dl></div></div><div class="refsect1" lang="en"><a name="id2479674"></a><h2>Administrative Commands</h2><p>
32 These are commands used to monitor and administrate a CTDB cluster.
33 </p><div class="refsect2" lang="en"><a name="id2479683"></a><h3>pnn</h3><p>
34 This command displays the pnn of the current node.
35 </p></div><div class="refsect2" lang="en"><a name="id2479693"></a><h3>status</h3><p>
36 This command shows the current status of the ctdb node.
37 </p><div class="refsect3" lang="en"><a name="id2479702"></a><h4>node status</h4><p>
38 Node status reflects the current status of the node. There are five possible states:
40 OK - This node is fully functional.
42 DISCONNECTED - This node could not be connected through the network and is currently not participating 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.
44 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.
46 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.
48 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.
49 </p></div><div class="refsect3" lang="en"><a name="id2479754"></a><h4>generation</h4><p>
50 The generation id is a number that indicates the current generation
51 of a cluster instance. Each time a cluster goes through a
52 reconfiguration or a recovery its generation id will be changed.
54 This number does not have any particular meaning other than to keep
55 track of when a cluster has gone through a recovery. It is a random
56 number that represents the current instance of a ctdb cluster
58 CTDBD uses this number internally to be able to tell when commands
59 to operate on the cluster and the databases was issued in a different
60 generation of the cluster, to ensure that commands that operate
61 on the databases will not survive across a cluster database recovery.
62 After a recovery, all old outstanding commands will automatically
65 Sometimes this number will be shown as "INVALID". This only means that
66 the ctdbd daemon has started but it has not yet merged with the cluster through a recovery.
67 All nodes start with generation "INVALID" and are not assigned a real
68 generation id until they have successfully been merged with a cluster
70 </p></div><div class="refsect3" lang="en"><a name="id2479789"></a><h4>VNNMAP</h4><p>
71 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.
72 Only nodes that are participating in the vnnmap can become lmaster or dmaster for a database record.
73 </p></div><div class="refsect3" lang="en"><a name="id2479803"></a><h4>Recovery mode</h4><p>
74 This is the current recovery mode of the cluster. There are two possible modes:
76 NORMAL - The cluster is fully operational.
78 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.
80 Once the recovery master detects an inconsistency, for example a node
81 becomes disconnected/connected, the recovery daemon will trigger a
82 cluster recovery process, where all databases are remerged across the
83 cluster. When this process starts, the recovery master will first
84 "freeze" all databases to prevent applications such as samba from
85 accessing the databases and it will also mark the recovery mode as
88 When CTDBD starts up, it will start in RECOVERY mode.
89 Once the node has been merged into a cluster and all databases
90 have been recovered, the node mode will change into NORMAL mode
91 and the databases will be "thawed", allowing samba to access the
93 </p></div><div class="refsect3" lang="en"><a name="id2528502"></a><h4>Recovery master</h4><p>
94 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.
96 Only one node at a time can be the designated recovery master. Which
97 node is designated the recovery master is decided by an election
98 process in the recovery daemons running on each node.
101 </p><p>Example output:</p><pre class="screen">
103 pnn:0 11.1.2.200 OK (THIS NODE)
107 Generation:1362079228
113 Recovery mode:NORMAL (0)
115 </pre></div><div class="refsect2" lang="en"><a name="id2528540"></a><h3>ping</h3><p>
116 This command will "ping" all CTDB daemons in the cluster to verify that they are processing commands correctly.
121 </p><pre class="screen">
122 response from 0 time=0.000054 sec (3 clients)
123 response from 1 time=0.000144 sec (2 clients)
124 response from 2 time=0.000105 sec (2 clients)
125 response from 3 time=0.000114 sec (2 clients)
126 </pre></div><div class="refsect2" lang="en"><a name="id2528566"></a><h3>ip</h3><p>
127 This command will display the list of public addresses that are provided by the cluster and which physical node is currently serving this ip.
132 </p><pre class="screen">
133 Number of addresses:4
138 </pre></div><div class="refsect2" lang="en"><a name="id2528591"></a><h3>getvar <name></h3><p>
139 Get the runtime value of a tuneable variable.
141 Example: ctdb getvar MaxRedirectCount
144 </p><pre class="screen">
146 </pre></div><div class="refsect2" lang="en"><a name="id2528610"></a><h3>setvar <name> <value></h3><p>
147 Set the runtime value of a tuneable variable.
149 Example: ctdb setvar MaxRedirectCount 5
150 </p></div><div class="refsect2" lang="en"><a name="id2528625"></a><h3>listvars</h3><p>
151 List all tuneable variables.
153 Example: ctdb listvars
156 </p><pre class="screen">
161 KeepaliveInterval = 2
169 EventScriptTimeout = 20
170 RecoveryGracePeriod = 60
171 RecoveryBanPeriod = 300
172 </pre></div><div class="refsect2" lang="en"><a name="id2528653"></a><h3>lvsmaster</h3><p>
173 This command shows which node is currently the LVSMASTER. The
174 LVSMASTER is the node in the cluster which drives the LVS system and
175 which receives all incoming traffic from clients.
177 LVS is the mode where the entire CTDB/Samba cluster uses a single
178 ip address for the entire cluster. In this mode all clients connect to
179 one specific node which will then multiplex/loadbalance the clients
180 evenly onto the other nodes in the cluster. This is an alternative to using
181 public ip addresses. See the manpage for ctdbd for more information
183 </p></div><div class="refsect2" lang="en"><a name="id2528675"></a><h3>lvs</h3><p>
184 This command shows which nodes in the cluster are currently active in the
185 LVS configuration. I.e. which nodes we are currently loadbalancing
186 the single ip address across.
188 LVS will by default only loadbalance across those nodes that are both
189 LVS capable and also HEALTHY. Except if all nodes are UNHEALTHY in which
190 case LVS will loadbalance across all UNHEALTHY nodes as well.
191 LVS will never use nodes that are DISCONNECTED, BANNED or DISABLED.
194 </p><pre class="screen">
197 </pre></div><div class="refsect2" lang="en"><a name="id2528705"></a><h3>getcapabilities</h3><p>
198 This command shows the capabilities of the current node.
199 Please see manpage for ctdbd for a full list of all capabilities and
200 more detailed description.
202 RECMASTER and LMASTER capabilities are primarily used when CTDBD
203 is used to create a cluster spanning across WAN links. In which case
204 ctdbd acts as a WAN accelerator.
206 LVS capabile means that the node is participating in LVS, a mode
207 where the entire CTDB cluster uses one single ip address for the
208 entire cluster instead of using public ip address failover.
209 This is an alternative to using a loadbalancing layer-4 switch.
212 </p><pre class="screen">
216 </pre></div><div class="refsect2" lang="en"><a name="id2528741"></a><h3>statistics</h3><p>
217 Collect statistics from the CTDB daemon about how many calls it has served.
219 Example: ctdb statistics
222 </p><pre class="screen">
227 client_packets_sent 360489
228 client_packets_recv 360466
229 node_packets_sent 480931
230 node_packets_recv 240120
231 keepalive_packets_sent 4
232 keepalive_packets_recv 3
253 pending_lockwait_calls 0
256 max_call_latency 4.948321 sec
257 max_lockwait_latency 0.000000 sec
258 </pre></div><div class="refsect2" lang="en"><a name="id2528784"></a><h3>statisticsreset</h3><p>
259 This command is used to clear all statistics counters in a node.
261 Example: ctdb statisticsreset
262 </p></div><div class="refsect2" lang="en"><a name="id2528799"></a><h3>getdebug</h3><p>
263 Get the current debug level for the node. the debug level controls what information is written to the log file.
265 The debug levels are mapped to the corresponding syslog levels.
266 When a debug level is set, only those messages at that level and higher
267 levels will be printed.
269 The list of debug levels from highest to lowest are :
271 EMERG ALERT CRIT ERR WARNING NOTICE INFO DEBUG
272 </p></div><div class="refsect2" lang="en"><a name="id2528825"></a><h3>setdebug <debuglevel></h3><p>
273 Set the debug level of a node. This controls what information will be logged.
275 The debuglevel is one of EMERG ALERT CRIT ERR WARNING NOTICE INFO DEBUG
276 </p></div><div class="refsect2" lang="en"><a name="id2528840"></a><h3>getpid</h3><p>
277 This command will return the process id of the ctdb daemon.
278 </p></div><div class="refsect2" lang="en"><a name="id2528850"></a><h3>disable</h3><p>
279 This command is used to administratively disable a node in the cluster.
280 A disabled node will still participate in the cluster and host
281 clustered TDB records but its public ip address has been taken over by
282 a different node and it no longer hosts any services.
283 </p></div><div class="refsect2" lang="en"><a name="id2528864"></a><h3>enable</h3><p>
284 Re-enable a node that has been administratively disabled.
285 </p></div><div class="refsect2" lang="en"><a name="id2528874"></a><h3>ban <bantime|0></h3><p>
286 Administratively ban a node for bantime seconds. A bantime of 0 means that the node should be permanently banned.
288 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.
290 Nodes are automatically banned if they are the cause of too many
292 </p></div><div class="refsect2" lang="en"><a name="id2528898"></a><h3>moveip <public_ip> <node></h3><p>
293 This command can be used to manually fail a public ip address to a
296 In order to manually override the "automatic" distribution of public
297 ip addresses that ctdb normally provides, this command only works
298 when you have changed the tunables for the daemon to:
303 </p></div><div class="refsect2" lang="en"><a name="id2528922"></a><h3>unban</h3><p>
304 This command is used to unban a node that has either been
305 administratively banned using the ban command or has been automatically
306 banned by the recovery daemon.
307 </p></div><div class="refsect2" lang="en"><a name="id2528934"></a><h3>shutdown</h3><p>
308 This command will shutdown a specific CTDB daemon.
309 </p></div><div class="refsect2" lang="en"><a name="id2528944"></a><h3>recover</h3><p>
310 This command will trigger the recovery daemon to do a cluster
312 </p></div><div class="refsect2" lang="en"><a name="id2528955"></a><h3>killtcp <srcip:port> <dstip:port></h3><p>
313 This command will kill the specified TCP connection by issuing a
314 TCP RST to the srcip:port endpoint.
315 </p></div><div class="refsect2" lang="en"><a name="id2528966"></a><h3>reloadnodes</h3><p>
316 This command is used when adding new nodes to an existing cluster and
317 to reduce the disruption of this operation. This command should never
318 be used except when expanding an existing cluster.
319 This can only be used to expand a cluster. To remove a node from the
320 cluster you still need to shut down ctdb on all nodes, edit the nodes file
325 1, To expand an existing cluster, first ensure with 'ctdb status' that
326 all nodes are up and running and that they are all healthy.
327 Do not try to expand a cluster unless it is completely healthy!
329 2, On all nodes, edit /etc/ctdb/nodes and add the new node as the last
330 entry to the file. The new node MUST be added to the end of this file!
332 3, Verify that all the nodes have identical /etc/ctdb/nodes files after you edited them and added the new node!
334 4, Run 'ctdb reloadnodes' to force all nodes to reaload the nodesfile.
336 5, Use 'ctdb status' on all nodes and verify that they now show the additional node.
338 6, Install and configure the new node and bring it online.
339 </p></div><div class="refsect2" lang="en"><a name="id2529018"></a><h3>tickle <srcip:port> <dstip:port></h3><p>
340 This command will will send a TCP tickle to the source host for the
341 specified TCP connection.
342 A TCP tickle is a TCP ACK packet with an invalid sequence and
343 acknowledge number and will when received by the source host result
344 in it sending an immediate correct ACK back to the other end.
346 TCP tickles are useful to "tickle" clients after a IP failover has
347 occured since this will make the client immediately recognize the
348 TCP connection has been disrupted and that the client will need
349 to reestablish. This greatly speeds up the time it takes for a client
350 to detect and reestablish after an IP failover in the ctdb cluster.
351 </p></div><div class="refsect2" lang="en"><a name="id2529043"></a><h3>repack [max_freelist]</h3><p>
352 Over time, when records are created and deleted in a TDB, the TDB list of free space will become fragmented. This can lead to a slowdown in accessing TDB records.
353 This command is used to defragment a TDB database and pruning the freelist.
355 If [max_freelist] is specified, then a database will only be repacked if it has more than this number of entries in the freelist.
357 During repacking of the database, the entire TDB database will be locked to prevent writes. If samba tries to write to a record in the database during a repack operation, samba will block until the repacking has completed.
359 This command can be disruptive and can cause samba to block for the duration of the repack operation. In general, a repack operation will take less than one second to complete.
361 A repack operation will only defragment the local TDB copy of the CTDB database. You need to run this command on all of the nodes to repack a CTDB database completely.
363 Example: ctdb repack 1000
365 By default, this operation is issued from the 00.ctdb event script every 5 minutes.
366 </p></div><div class="refsect2" lang="en"><a name="id2529089"></a><h3>vacuum [max_records]</h3><p>
367 Over time CTDB databases will fill up with empty deleted records which will lead to a progressive slow down of CTDB database access.
368 This command is used to prune all databases and delete all empty records from the cluster.
370 By default, vacuum will delete all empty records from all databases.
371 If [max_records] is specified, the command will only delete the first
372 [max_records] empty records for each database.
374 Vacuum only deletes records where the local node is the lmaster.
375 To delete all records from the entire cluster you need to run a vacuum from each node.
377 This command is not disruptive. Samba is unaffected and will still be able to read/write records normally while the database is being vacuumed.
381 By default, this operation is issued from the 00.ctdb event script every 5 minutes.
382 </p></div></div><div class="refsect1" lang="en"><a name="id2529126"></a><h2>Debugging Commands</h2><p>
383 These commands are primarily used for CTDB development and testing and
384 should not be used for normal administration.
385 </p><div class="refsect2" lang="en"><a name="id2529136"></a><h3>process-exists <pid></h3><p>
386 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.
387 </p></div><div class="refsect2" lang="en"><a name="id2529149"></a><h3>getdbmap</h3><p>
388 This command lists all clustered TDB databases that the CTDB daemon has attached to. Some databases are flagged as PERSISTENT, this means that the database stores data persistently and the data will remain across reboots. One example of such a database is secrets.tdb where information about how the cluster was joined to the domain is stored.
390 Most databases are not persistent and only store the state information that the currently running samba daemons need. These databases are always wiped when ctdb/samba starts and when a node is rebooted.
392 Example: ctdb getdbmap
395 </p><pre class="screen">
396 Number of databases:10
397 dbid:0x435d3410 name:notify.tdb path:/var/ctdb/notify.tdb.0
398 dbid:0x42fe72c5 name:locking.tdb path:/var/ctdb/locking.tdb.0 dbid:0x1421fb78 name:brlock.tdb path:/var/ctdb/brlock.tdb.0
399 dbid:0x17055d90 name:connections.tdb path:/var/ctdb/connections.tdb.0
400 dbid:0xc0bdde6a name:sessionid.tdb path:/var/ctdb/sessionid.tdb.0
401 dbid:0x122224da name:test.tdb path:/var/ctdb/test.tdb.0
402 dbid:0x2672a57f name:idmap2.tdb path:/var/ctdb/persistent/idmap2.tdb.0 PERSISTENT
403 dbid:0xb775fff6 name:secrets.tdb path:/var/ctdb/persistent/secrets.tdb.0 PERSISTENT
404 dbid:0xe98e08b6 name:group_mapping.tdb path:/var/ctdb/persistent/group_mapping.tdb.0 PERSISTENT
405 dbid:0x7bbbd26c name:passdb.tdb path:/var/ctdb/persistent/passdb.tdb.0 PERSISTENT
406 </pre></div><div class="refsect2" lang="en"><a name="id2529195"></a><h3>catdb <dbname></h3><p>
407 This command will dump a clustered TDB database to the screen. This is a debugging command.
408 </p></div><div class="refsect2" lang="en"><a name="id2529206"></a><h3>getmonmode</h3><p>
409 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.
411 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.
413 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.
414 </p></div><div class="refsect2" lang="en"><a name="id2529236"></a><h3>setmonmode <0|1></h3><p>
415 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.
416 </p></div><div class="refsect2" lang="en"><a name="id2529252"></a><h3>attach <dbname></h3><p>
417 This is a debugging command. This command will make the CTDB daemon create a new CTDB database and attach to it.
418 </p></div><div class="refsect2" lang="en"><a name="id2529263"></a><h3>dumpmemory</h3><p>
419 This is a debugging command. This command will make the ctdb
420 daemon to write a fill memory allocation map to standard output.
421 </p></div><div class="refsect2" lang="en"><a name="id2529275"></a><h3>freeze</h3><p>
422 This command will lock all the local TDB databases causing clients
423 that are accessing these TDBs such as samba3 to block until the
424 databases are thawed.
426 This is primarily used by the recovery daemon to stop all samba
427 daemons from accessing any databases while the database is recovered
429 </p></div><div class="refsect2" lang="en"><a name="id2529293"></a><h3>thaw</h3><p>
430 Thaw a previously frozen node.
431 </p></div></div><div class="refsect1" lang="en"><a name="id2529304"></a><h2>SEE ALSO</h2><p>
433 <a class="ulink" href="http://ctdb.samba.org/" target="_top">http://ctdb.samba.org/</a>
434 </p></div><div class="refsect1" lang="en"><a name="id2529317"></a><h2>COPYRIGHT/LICENSE</h2><div class="literallayout"><p><br>
435 Copyright (C) Andrew Tridgell 2007<br>
436 Copyright (C) Ronnie sahlberg 2007<br>
438 This program is free software; you can redistribute it and/or modify<br>
439 it under the terms of the GNU General Public License as published by<br>
440 the Free Software Foundation; either version 3 of the License, or (at<br>
441 your option) any later version.<br>
443 This program is distributed in the hope that it will be useful, but<br>
444 WITHOUT ANY WARRANTY; without even the implied warranty of<br>
445 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU<br>
446 General Public License for more details.<br>
448 You should have received a copy of the GNU General Public License<br>
449 along with this program; if not, see http://www.gnu.org/licenses/.<br>
450 </p></div></div></div></body></html>