samba-mirror/ctdb/doc/ctdb.1.xml

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<!DOCTYPE refentry
	PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
	"http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd">
<refentry id="ctdb.1">

  <refentryinfo>
    <author>
      <contrib>
	This documentation was written by
	Ronnie Sahlberg,
	Amitay Isaacs,
	Martin Schwenke
      </contrib>
    </author>

    <copyright>
      <year>2007</year>
      <holder>Andrew Tridgell</holder>
      <holder>Ronnie Sahlberg</holder>
    </copyright>
    <legalnotice>
      <para>
	This program is free software; you can redistribute it and/or
	modify it under the terms of the GNU General Public License as
	published by the Free Software Foundation; either version 3 of
	the License, or (at your option) any later version.
      </para>
      <para>
	This program is distributed in the hope that it will be
	useful, but WITHOUT ANY WARRANTY; without even the implied
	warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
	PURPOSE.  See the GNU General Public License for more details.
      </para>
      <para>
	You should have received a copy of the GNU General Public
	License along with this program; if not, see
	<ulink url="http://www.gnu.org/licenses"/>.
      </para>
    </legalnotice>
  </refentryinfo>

  <refmeta>
    <refentrytitle>ctdb</refentrytitle>
    <manvolnum>1</manvolnum>
    <refmiscinfo class="source">ctdb</refmiscinfo>
    <refmiscinfo class="manual">CTDB - clustered TDB database</refmiscinfo>
  </refmeta>

  <refnamediv>
    <refname>ctdb</refname>
    <refpurpose>CTDB management utility</refpurpose>
  </refnamediv>

  <refsynopsisdiv>
    <cmdsynopsis>
      <command>ctdb</command>
      <arg rep="repeat"><replaceable>OPTION</replaceable></arg>
      <arg choice="req"><replaceable>COMMAND</replaceable></arg>
      <arg choice="opt"><replaceable>COMMAND-ARGS</replaceable></arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1>
    <title>DESCRIPTION</title>
    <para>
      ctdb is a utility to view and manage a CTDB cluster.
    </para>

    <para>
      The following terms are used when referring to nodes in a
      cluster:
      <variablelist>
	<varlistentry>
	  <term>PNN</term>
	  <listitem>
	    <para>
	      Physical Node Number.  The physical node number is an
	      integer that describes the node in the cluster. The
	      first node has physical node number 0.  in a cluster.
	    </para>
	  </listitem>
	</varlistentry>
	<varlistentry>
	  <term>PNN-LIST</term>
	  <listitem>
	    <para>
	      This is either a single PNN, a comma-separate list of PNNs
	      or "all".
	    </para>
	  </listitem>
	</varlistentry>
      </variablelist>
    </para>

    <para>
      Commands that reference a database use the following terms:
      <variablelist>
	<varlistentry>
	  <term>DB</term>
	  <listitem>
	    <para>
	      This is either a database name, such as
	      <filename>locking.tdb</filename> or a database ID such
	      as "0x42fe72c5".
	    </para>
	  </listitem>
	</varlistentry>
	<varlistentry>
	  <term>DB-LIST</term>
	  <listitem>
	    <para>
	      A space separated list of at least one
	      <parameter>DB</parameter>.
	    </para>
	  </listitem>
	</varlistentry>
      </variablelist>
    </para>
  </refsect1>

  <refsect1>
    <title>OPTIONS</title>

    <variablelist>
      <varlistentry><term>-n <parameter>PNN-LIST</parameter></term>
      <listitem>
	<para>
	  The nodes specified by PNN-LIST should be queried for the
	  requested information.  Default is to query the daemon
	  running on the local host.
	</para>
      </listitem>
      </varlistentry>

      <varlistentry><term>-Y</term>
      <listitem>
	<para>
	  Produce output in machine readable form for easier parsing
	  by scripts. Not all commands support this option.
	</para>
      </listitem>
      </varlistentry>

      <varlistentry><term>-t <parameter>TIMEOUT</parameter></term>
      <listitem>
	<para>
	  Indicates that ctdb should wait up to TIMEOUT seconds for
	  a response to most commands sent to the CTDB daemon.  The
	  default is 10 seconds.
	</para>
      </listitem>
      </varlistentry>

      <varlistentry><term>-T <parameter>TIMELIMIT</parameter></term>
      <listitem>
	<para>
	  Indicates that TIMELIMIT is the maximum run time (in
	  seconds) for the ctdb command.  When TIMELIMIT is exceeded
	  the ctdb command will terminate with an error.  The default
	  is 120 seconds.
	</para>
      </listitem>
      </varlistentry>

      <varlistentry><term>-? --help</term>
      <listitem>
	<para>
	  Print some help text to the screen.
	</para>
      </listitem>
      </varlistentry>

      <varlistentry><term>--usage</term>
      <listitem>
	<para>
	  Print useage information to the screen.
	</para>
      </listitem>
      </varlistentry>

      <varlistentry><term>-d --debug=<parameter>DEBUGLEVEL</parameter></term>
      <listitem>
	<para>
	  Change the debug level for the command. Default is ERR (0).
	</para>
      </listitem>
      </varlistentry>

      <varlistentry><term>--socket=<parameter>FILENAME</parameter></term>
      <listitem>
	<para>
	  Specify that FILENAME is the name of the Unix domain
	  socket to use when connecting to the local CTDB
	  daemon. The default is
	  <filename>/tmp/ctdb.socket</filename>.
	</para>
      </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>


  <refsect1>
    <title>ADMINISTRATIVE COMMANDS</title>
    <para>
      These are commands used to monitor and administer a CTDB cluster.
    </para>

    <refsect2>
      <title>pnn</title>
      <para>
	This command displays the PNN of the current node.
      </para>
    </refsect2>

    <refsect2>
      <title>xpnn</title>
      <para>
	This command displays the PNN of the current node without
	contacting the CTDB daemon.  It parses the nodes file
	directly, so can produce unexpected output if the nodes file
	has been edited but has not been reloaded.
      </para>
    </refsect2>

    <refsect2>
      <title>status</title>
      <para>
	This command shows the current status of all CTDB nodes based
	on information from the queried node.
      </para>

      <para>
	Note: If the the queried node is INACTIVE then the status
	might not be current.
      </para>

      <refsect3>
	<title>Node status</title>
	<para>
	  This includes the number of physical nodes and the status of
	  each node.  See <citerefentry><refentrytitle>ctdb</refentrytitle>
	  <manvolnum>7</manvolnum></citerefentry> for information
	  about node states.
	</para>
      </refsect3>

      <refsect3>
	<title>Generation</title>
	<para>
	  The generation id is a number that indicates the current generation 
	  of a cluster instance. Each time a cluster goes through a 
	  reconfiguration or a recovery its generation id will be changed.
	</para>
	<para>
	  This number does not have any particular meaning other than
	  to keep track of when a cluster has gone through a
	  recovery. It is a random number that represents the current
	  instance of a ctdb cluster and its databases.  The CTDB
	  daemon uses this number internally to be able to tell when
	  commands to operate on the cluster and the databases was
	  issued in a different generation of the cluster, to ensure
	  that commands that operate on the databases will not survive
	  across a cluster database recovery.  After a recovery, all
	  old outstanding commands will automatically become invalid.
	</para>
	<para>
	  Sometimes this number will be shown as "INVALID". This only means that
	  the ctdbd daemon has started but it has not yet merged with the cluster through a recovery.
	  All nodes start with generation "INVALID" and are not assigned a real
	  generation id until they have successfully been merged with a cluster
	  through a recovery.
	</para>
      </refsect3>

      <refsect3>
	<title>Virtual Node Number (VNN) map</title>
	<para>
	  Consists of the number of virtual nodes and mapping from
	  virtual node numbers to physical node numbers.  Virtual
	  nodes host CTDB databases.  Only nodes that are
	  participating in the VNN map can become lmaster or dmaster
	  for database records.
	</para>
      </refsect3>

      <refsect3>
	<title>Recovery mode</title>
	<para>
	  This is the current recovery mode of the cluster. There are two possible modes:
	</para>
	<para>
	  NORMAL - The cluster is fully operational.
	</para>
	<para>
	  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.
	</para>
	<para>
	  Once the recovery master detects an inconsistency, for example a node 
	  becomes disconnected/connected, the recovery daemon will trigger a 
	  cluster recovery process, where all databases are remerged across the
	  cluster. When this process starts, the recovery master will first
	  "freeze" all databases to prevent applications such as samba from 
	  accessing the databases and it will also mark the recovery mode as
	  RECOVERY.
	</para>
	<para>
	  When the CTDB daemon starts up, it will start in RECOVERY
	  mode.  Once the node has been merged into a cluster and all
	  databases have been recovered, the node mode will change into
	  NORMAL mode and the databases will be "thawed", allowing samba
	  to access the databases again.
	</para>
      </refsect3>
      <refsect3>
	<title>Recovery master</title>
	<para>
	  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.
	</para>
	<para>
	  Only one node at a time can be the designated recovery master. Which
	  node is designated the recovery master is decided by an election
	  process in the recovery daemons running on each node.
	</para>
      </refsect3>

      <refsect3>
	<title>Example</title>
	<screen>
# ctdb status
Number of nodes:4
pnn:0 192.168.2.200       OK (THIS NODE)
pnn:1 192.168.2.201       OK
pnn:2 192.168.2.202       OK
pnn:3 192.168.2.203       OK
Generation:1362079228
Size:4
hash:0 lmaster:0
hash:1 lmaster:1
hash:2 lmaster:2
hash:3 lmaster:3
Recovery mode:NORMAL (0)
Recovery master:0
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>nodestatus <optional><parameter>PNN-LIST</parameter></optional></title>
      <para>
	This command is similar to the <command>status</command>
	command.  It displays the "node status" subset of output.  The
	main differences are:
      </para>

      <itemizedlist>
	<listitem>
	  <para>
	    The exit code is the bitwise-OR of the flags for each
	    specified node, while <command>ctdb status</command> exits
	    with 0 if it was able to retrieve status for all nodes.
	  </para>
	</listitem>

	<listitem>
	  <para>
	    <command>ctdb status</command> provides status information
	    for all nodes.  <command>ctdb nodestatus</command>
	    defaults to providing status for only the current node.
	    If PNN-LIST is provided then status is given for
	    the indicated node(s).
	  </para>

	  <para>
	    By default, <command>ctdb nodestatus</command> gathers
	    status from the local node.  However, if invoked with "-n
	    all" (or similar) then status is gathered from the given
	    node(s).  In particular <command>ctdb nodestatus
	    all</command> and <command>ctdb nodestatus -n
	    all</command> will produce different output.  It is
	    possible to provide 2 different nodespecs (with and
	    without "-n") but the output is usually confusing!
	  </para>
	</listitem>
      </itemizedlist>

      <para>
	A common invocation in scripts is <command>ctdb nodestatus
	all</command> to check whether all nodes in a cluster are
	healthy.
      </para>

      <refsect3>
	<title>Example</title>
	<screen>
# ctdb nodestatus
pnn:0 10.0.0.30        OK (THIS NODE)

# ctdb nodestatus all
Number of nodes:2
pnn:0 10.0.0.30        OK (THIS NODE)
pnn:1 10.0.0.31        OK
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>recmaster</title>
      <para>
	This command shows the pnn of the node which is currently the recmaster.
      </para>

      <para>
	Note: If the the queried node is INACTIVE then the status
	might not be current.
      </para>
    </refsect2>

    <refsect2>
      <title>uptime</title>
      <para>
	This command shows the uptime for the ctdb daemon. When the last recovery or ip-failover completed and how long it took. If the "duration" is shown as a negative number, this indicates that there is a recovery/failover in progress and it started that many seconds ago.
      </para>

      <refsect3>
	<title>Example</title>
	<screen>
# ctdb uptime
Current time of node          :                Thu Oct 29 10:38:54 2009
Ctdbd start time              : (000 16:54:28) Wed Oct 28 17:44:26 2009
Time of last recovery/failover: (000 16:53:31) Wed Oct 28 17:45:23 2009
Duration of last recovery/failover: 2.248552 seconds
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>listnodes</title>
      <para>
	This command shows lists the ip addresses of all the nodes in the cluster.
      </para>

      <refsect3>
	<title>Example</title>
	<screen>
# ctdb listnodes
192.168.2.200
192.168.2.201
192.168.2.202
192.168.2.203
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>natgwlist</title>
      <para>
	Show the current NAT gateway master and the status of all
	nodes in the current NAT gateway group.  See the
	<citetitle>NAT GATEWAY</citetitle> section in
	<citerefentry><refentrytitle>ctdb</refentrytitle>
	<manvolnum>7</manvolnum></citerefentry> for more details.
      </para>

      <refsect3>
	<title>Example</title>
	<screen>
# ctdb natgwlist
0 192.168.2.200
Number of nodes:4
pnn:0 192.168.2.200       OK (THIS NODE)
pnn:1 192.168.2.201       OK
pnn:2 192.168.2.202       OK
pnn:3 192.168.2.203       OK
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>ping</title>
      <para>
	This command will "ping" specified CTDB nodes in the cluster
	to verify that they are running.
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb ping -n all
response from 0 time=0.000054 sec  (3 clients)
response from 1 time=0.000144 sec  (2 clients)
response from 2 time=0.000105 sec  (2 clients)
response from 3 time=0.000114 sec  (2 clients)
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>ifaces</title>
      <para>
	This command will display the list of network interfaces, which could
	host public addresses, along with their status.
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb ifaces
Interfaces on node 0
name:eth5 link:up references:2
name:eth4 link:down references:0
name:eth3 link:up references:1
name:eth2 link:up references:1

# ctdb ifaces -Y
:Name:LinkStatus:References:
:eth5:1:2
:eth4:0:0
:eth3:1:1
:eth2:1:1
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>ip</title>
      <para>
	This command will display the list of public addresses that are provided by the cluster and which physical node is currently serving this ip. By default this command will ONLY show those public addresses that are known to the node itself. To see the full list of all public ips across the cluster you must use "ctdb ip -n all".
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb ip
Public IPs on node 0
172.31.91.82 node[1] active[] available[eth2,eth3] configured[eth2,eth3]
172.31.91.83 node[0] active[eth3] available[eth2,eth3] configured[eth2,eth3]
172.31.91.84 node[1] active[] available[eth2,eth3] configured[eth2,eth3]
172.31.91.85 node[0] active[eth2] available[eth2,eth3] configured[eth2,eth3]
172.31.92.82 node[1] active[] available[eth5] configured[eth4,eth5]
172.31.92.83 node[0] active[eth5] available[eth5] configured[eth4,eth5]
172.31.92.84 node[1] active[] available[eth5] configured[eth4,eth5]
172.31.92.85 node[0] active[eth5] available[eth5] configured[eth4,eth5]

# ctdb ip -Y
:Public IP:Node:ActiveInterface:AvailableInterfaces:ConfiguredInterfaces:
:172.31.91.82:1::eth2,eth3:eth2,eth3:
:172.31.91.83:0:eth3:eth2,eth3:eth2,eth3:
:172.31.91.84:1::eth2,eth3:eth2,eth3:
:172.31.91.85:0:eth2:eth2,eth3:eth2,eth3:
:172.31.92.82:1::eth5:eth4,eth5:
:172.31.92.83:0:eth5:eth5:eth4,eth5:
:172.31.92.84:1::eth5:eth4,eth5:
:172.31.92.85:0:eth5:eth5:eth4,eth5:
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>ipinfo <parameter>IP</parameter></title>
      <para>
	This command will display details about the specified public addresses.
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb ipinfo 172.31.92.85
Public IP[172.31.92.85] info on node 0
IP:172.31.92.85
CurrentNode:0
NumInterfaces:2
Interface[1]: Name:eth4 Link:down References:0
Interface[2]: Name:eth5 Link:up References:2 (active)
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>scriptstatus</title>
      <para>
	This command displays which scripts where run in the previous monitoring cycle and the result of each script. If a script failed with an error, causing the node to become unhealthy, the output from that script is also shown.
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb scriptstatus
7 scripts were executed last monitoring cycle
00.ctdb              Status:OK    Duration:0.056 Tue Mar 24 18:56:57 2009
10.interface         Status:OK    Duration:0.077 Tue Mar 24 18:56:57 2009
11.natgw             Status:OK    Duration:0.039 Tue Mar 24 18:56:57 2009
20.multipathd        Status:OK    Duration:0.038 Tue Mar 24 18:56:57 2009
31.clamd             Status:DISABLED
40.vsftpd            Status:OK    Duration:0.045 Tue Mar 24 18:56:57 2009
41.httpd             Status:OK    Duration:0.039 Tue Mar 24 18:56:57 2009
50.samba             Status:ERROR    Duration:0.082 Tue Mar 24 18:56:57 2009
OUTPUT:ERROR: Samba tcp port 445 is not responding
      </screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>disablescript <parameter>SCRIPT</parameter></title>
      <para>
	This command is used to disable an eventscript.
      </para>
      <para>
	This will take effect the next time the eventscripts are being executed so it can take a short while until this is reflected in 'scriptstatus'.
      </para>
    </refsect2>

    <refsect2>
      <title>enablescript <parameter>SCRIPT</parameter></title>
      <para>
	This command is used to enable an eventscript.
      </para>
      <para>
	This will take effect the next time the eventscripts are being executed so it can take a short while until this is reflected in 'scriptstatus'.
      </para>
    </refsect2>

    <refsect2>
      <title>listvars</title>
      <para>
	List all tuneable variables, except the values of the obsolete tunables
	like VacuumMinInterval. The obsolete tunables can be retrieved only
	explicitly with the "ctdb getvar" command.
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb listvars
MaxRedirectCount        = 3
SeqnumInterval          = 1000
ControlTimeout          = 60
TraverseTimeout         = 20
KeepaliveInterval       = 5
KeepaliveLimit          = 5
RecoverTimeout          = 20
RecoverInterval         = 1
ElectionTimeout         = 3
TakeoverTimeout         = 9
MonitorInterval         = 15
TickleUpdateInterval    = 20
EventScriptTimeout      = 30
EventScriptTimeoutCount = 1
RecoveryGracePeriod     = 120
RecoveryBanPeriod       = 300
DatabaseHashSize        = 100001
DatabaseMaxDead         = 5
RerecoveryTimeout       = 10
EnableBans              = 1
DeterministicIPs        = 0
LCP2PublicIPs           = 1
ReclockPingPeriod       = 60
NoIPFailback            = 0
DisableIPFailover       = 0
VerboseMemoryNames      = 0
RecdPingTimeout         = 60
RecdFailCount           = 10
LogLatencyMs            = 0
RecLockLatencyMs        = 1000
RecoveryDropAllIPs      = 120
VerifyRecoveryLock      = 1
VacuumInterval          = 10
VacuumMaxRunTime        = 30
RepackLimit             = 10000
VacuumLimit             = 5000
VacuumFastPathCount     = 60
MaxQueueDropMsg         = 1000000
UseStatusEvents         = 0
AllowUnhealthyDBRead    = 0
StatHistoryInterval     = 1
DeferredAttachTO        = 120
AllowClientDBAttach     = 1
RecoverPDBBySeqNum      = 0
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>getvar <parameter>NAME</parameter></title>
      <para>
	Get the runtime value of a tuneable variable.
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb getvar MaxRedirectCount
MaxRedirectCount    = 3
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>setvar <parameter>NAME</parameter> <parameter>VALUE</parameter></title>
      <para>
	Set the runtime value of a tuneable variable.
      </para>
      <para>
	Example: ctdb setvar MaxRedirectCount 5
      </para>
    </refsect2>

    <refsect2>
      <title>lvsmaster</title>
      <para>
	This command shows which node is currently the LVSMASTER. The
	LVSMASTER is the node in the cluster which drives the LVS system and
	which receives all incoming traffic from clients.
      </para>
      <para>
	LVS is the mode where the entire CTDB/Samba cluster uses a single
	ip address for the entire cluster. In this mode all clients connect to
	one specific node which will then multiplex/loadbalance the clients
	evenly onto the other nodes in the cluster. This is an alternative to using
	public ip addresses. See the manpage for ctdbd for more information
	about LVS.
      </para>
    </refsect2>

    <refsect2>
      <title>lvs</title>
      <para>
	This command shows which nodes in the cluster are currently active in the
	LVS configuration. I.e. which nodes we are currently loadbalancing
	the single ip address across.
      </para>

      <para>
	LVS will by default only loadbalance across those nodes that are both
	LVS capable and also HEALTHY. Except if all nodes are UNHEALTHY in which
	case LVS will loadbalance across all UNHEALTHY nodes as well.
	LVS will never use nodes that are DISCONNECTED, STOPPED, BANNED or
	DISABLED.
      </para>

      <para>
	Example output:
      </para>
      <screen>
2:10.0.0.13
3:10.0.0.14
      </screen>

    </refsect2>


    <refsect2>
      <title>getcapabilities</title>

      <para>
	This command shows the capabilities of the current node.  See
	the <citetitle>CAPABILITIES</citetitle> section in
	<citerefentry><refentrytitle>ctdb</refentrytitle>
	<manvolnum>7</manvolnum></citerefentry> for more details.
      </para>

      <para>
	Example output:
      </para>
      <screen>
RECMASTER: YES
LMASTER: YES
LVS: NO
NATGW: YES
      </screen>

    </refsect2>

    <refsect2>
      <title>statistics</title>
      <para>
	Collect statistics from the CTDB daemon about how many calls it has served.
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb statistics
CTDB version 1
num_clients                        3
frozen                             0
recovering                         0
client_packets_sent           360489
client_packets_recv           360466
node_packets_sent             480931
node_packets_recv             240120
keepalive_packets_sent             4
keepalive_packets_recv             3
node
req_call                       2
reply_call                     2
req_dmaster                    0
reply_dmaster                  0
reply_error                    0
req_message                   42
req_control               120408
reply_control             360439
client
req_call                       2
req_message                   24
req_control               360440
timeouts
call                           0
control                        0
traverse                       0
total_calls                        2
pending_calls                      0
lockwait_calls                     0
pending_lockwait_calls             0
memory_used                     5040
max_hop_count                      0
max_call_latency                   4.948321 sec
max_lockwait_latency               0.000000 sec
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>statisticsreset</title>
      <para>
	This command is used to clear all statistics counters in a node.
      </para>
      <para>
	Example: ctdb statisticsreset
      </para>
    </refsect2>

    <refsect2>
      <title>dbstatistics <parameter>DB</parameter></title>
      <para>
	Display statistics about the database DB.
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb dbstatistics locking.tdb
DB Statistics: locking.tdb
 ro_delegations                     0
 ro_revokes                         0
 locks
     total                      14356
     failed                         0
     current                        0
     pending                        0
 hop_count_buckets: 28087 2 1 0 0 0 0 0 0 0 0 0 0 0 0 0
 lock_buckets: 0 14188 38 76 32 19 3 0 0 0 0 0 0 0 0 0
 locks_latency      MIN/AVG/MAX     0.001066/0.012686/4.202292 sec out of 14356
 Num Hot Keys:     1
     Count:8 Key:ff5bd7cb3ee3822edc1f0000000000000000000000000000
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>getreclock</title>
      <para>
	This command is used to show the filename of the reclock file that is used.
      </para>

      <para>
	Example output:
      </para>
      <screen>
	Reclock file:/gpfs/.ctdb/shared
      </screen>

    </refsect2>

    <refsect2>
      <title>setreclock [filename]</title>
      <para>
	This command is used to modify, or clear, the file that is used as the reclock file at runtime. When this command is used, the reclock file checks are disabled. To re-enable the checks the administrator needs to activate the "VerifyRecoveryLock" tunable using "ctdb setvar".
      </para>

      <para>
	If run with no parameter this will remove the reclock file completely. If run with a parameter the parameter specifies the new filename to use for the recovery lock.
      </para>

      <para>
	This command only affects the runtime settings of a ctdb node and will be lost when ctdb is restarted. For persistent changes to the reclock file setting you must edit /etc/sysconfig/ctdb.
      </para>
    </refsect2>



    <refsect2>
      <title>getdebug</title>
      <para>
	Get the current debug level for the node. the debug level controls what information is written to the log file.
      </para>
      <para>
	The debug levels are mapped to the corresponding syslog levels.
	When a debug level is set, only those messages at that level and higher
	levels will be printed.
      </para>
      <para>
	The list of debug levels from highest to lowest are :
      </para>
      <para>
	EMERG ALERT CRIT ERR WARNING NOTICE INFO DEBUG
      </para>
    </refsect2>

    <refsect2>
      <title>setdebug <parameter>DEBUGLEVEL</parameter></title>
      <para>
	Set the debug level of a node. This controls what information will be logged.
      </para>
      <para>
	The debuglevel is one of EMERG ALERT CRIT ERR WARNING NOTICE INFO DEBUG
      </para>
    </refsect2>

    <refsect2>
      <title>getpid</title>
      <para>
	This command will return the process id of the ctdb daemon.
      </para>
    </refsect2>

    <refsect2>
      <title>disable</title>
      <para>
	This command is used to administratively disable a node in the cluster.
	A disabled node will still participate in the cluster and host
	clustered TDB records but its public ip address has been taken over by
	a different node and it no longer hosts any services.
      </para>
    </refsect2>

    <refsect2>
      <title>enable</title>
      <para>
	Re-enable a node that has been administratively disabled.
      </para>
    </refsect2>

    <refsect2>
      <title>stop</title>
      <para>
	This command is used to administratively STOP a node in the cluster.
	A STOPPED node is connected to the cluster but will not host any
	public ip addresse, nor does it participate in the VNNMAP.
	The difference between a DISABLED node and a STOPPED node is that
	a STOPPED node does not host any parts of the database which means
	that a recovery is required to stop/continue nodes.
      </para>
    </refsect2>

    <refsect2>
      <title>continue</title>
      <para>
	Re-start a node that has been administratively stopped.
      </para>
    </refsect2>

    <refsect2>
      <title>addip <parameter>IPADDR</parameter>/<parameter>mask</parameter> <parameter>IFACE</parameter></title>
      <para>
	This command is used to add a new public ip to a node during runtime.
	This allows public addresses to be added to a cluster without having
	to restart the ctdb daemons.
      </para>
      <para>
	Note that this only updates the runtime instance of ctdb. Any changes will be lost next time ctdb is restarted and the public addresses file is re-read.
	If you want this change to be permanent you must also update the public addresses file manually.
      </para>
    </refsect2>

    <refsect2>
      <title>delip <parameter>IPADDR</parameter></title>
      <para>
	This command is used to remove a public ip from a node during runtime.
	If this public ip is currently hosted by the node it being removed from, the ip will first be failed over to another node, if possible, before it is removed.
      </para>
      <para>
	Note that this only updates the runtime instance of ctdb. Any changes will be lost next time ctdb is restarted and the public addresses file is re-read.
	If you want this change to be permanent you must also update the public addresses file manually.
      </para>
    </refsect2>

    <refsect2>
      <title>moveip <parameter>IPADDR</parameter> <parameter>PNN</parameter></title>
      <para>
	This command can be used to manually fail a public ip address to a
	specific node.
      </para>
      <para>
	In order to manually override the "automatic" distribution of public 
	ip addresses that ctdb normally provides, this command only works
	when you have changed the tunables for the daemon to:
      </para>
      <para>
	DeterministicIPs = 0
      </para>
      <para>
	NoIPFailback = 1
      </para>
    </refsect2>

    <refsect2>
      <title>shutdown</title>
      <para>
	This command will shutdown a specific CTDB daemon.
      </para>
    </refsect2>

    <refsect2>
      <title>setlmasterrole on|off</title>
      <para>
	This command is used ot enable/disable the LMASTER capability for a node at runtime. This capability determines whether or not a node can be used as an LMASTER for records in the database. A node that does not have the LMASTER capability will not show up in the vnnmap.
      </para>

      <para>
	Nodes will by default have this capability, but it can be stripped off nodes by the setting in the sysconfig file or by using this command.
      </para>
      <para>
	Once this setting has been enabled/disabled, you need to perform a recovery for it to take effect.
      </para>
      <para>
	See also "ctdb getcapabilities"
      </para>
    </refsect2>

    <refsect2>
      <title>setrecmasterrole on|off</title>
      <para>
	This command is used ot enable/disable the RECMASTER capability for a node at runtime. This capability determines whether or not a node can be used as an RECMASTER for the cluster. A node that does not have the RECMASTER capability can not win a recmaster election. A node that already is the recmaster for the cluster when the capability is stripped off the node will remain the recmaster until the next cluster election.
      </para>

      <para>
	Nodes will by default have this capability, but it can be stripped off nodes by the setting in the sysconfig file or by using this command.
      </para>
      <para>
	See also "ctdb getcapabilities"
      </para>
    </refsect2>

    <refsect2>
      <title>reloadnodes</title>
      <para>
	This command is used when adding new nodes, or removing existing nodes from an existing cluster.
      </para>
      <para>
	Procedure to add a node:
      </para>
      <para>
	1, To expand an existing cluster, first ensure with 'ctdb status' that
	all nodes are up and running and that they are all healthy.
	Do not try to expand a cluster unless it is completely healthy!
      </para>
      <para>
	2, On all nodes, edit /etc/ctdb/nodes and add the new node as the last
	entry to the file. The new node MUST be added to the end of this file!
      </para>
      <para>
	3, Verify that all the nodes have identical /etc/ctdb/nodes files after you edited them and added the new node!
      </para>
      <para>
	4, Run 'ctdb reloadnodes' to force all nodes to reload the nodesfile.
      </para>
      <para>
	5, Use 'ctdb status' on all nodes and verify that they now show the additional node.
      </para>
      <para>
	6, Install and configure the new node and bring it online.
      </para>
      <para>
	Procedure to remove a node:
      </para>
      <para>
	1, To remove a node from an existing cluster, first ensure with 'ctdb status' that
	all nodes, except the node to be deleted, are up and running and that they are all healthy.
	Do not try to remove a node from a cluster unless the cluster is completely healthy!
      </para>
      <para>
	2, Shutdown and poweroff the node to be removed.
      </para>
      <para>
	3, On all other nodes, edit the /etc/ctdb/nodes file and comment out the node to be removed. Do not delete the line for that node, just comment it out by adding a '#' at the beginning of the line.
      </para>
      <para>
	4, Run 'ctdb reloadnodes' to force all nodes to reload the nodesfile.
      </para>
      <para>
	5, Use 'ctdb status' on all nodes and verify that the deleted node no longer shows up in the list..
      </para>
      <para>
      </para>

    </refsect2>

    <refsect2>
      <title>
	reloadips
	<optional><parameter>PNN-LIST</parameter></optional>
      </title>
      <para>
	This command reloads the public addresses configuration file
	on the specified nodes.  When it completes addresses will be
	reconfigured and reassigned across the cluster as necessary.
      </para>
    </refsect2>

    <refsect2>
      <title>getdbmap</title>
      <para>
	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.
      </para>
      <para>
	If a PERSISTENT database is not in a healthy state the database is
	flagged as UNHEALTHY. If there's at least one completely healthy node running in
	the cluster, it's possible that the content is restored by a recovery
	run automaticly. Otherwise an administrator needs to analyze the
	problem.
      </para>
      <para>
	See also "ctdb getdbstatus", "ctdb backupdb", "ctdb restoredb",
	"ctdb dumpbackup", "ctdb wipedb", "ctdb setvar AllowUnhealthyDBRead 1"
	and (if samba or tdb-utils are installed) "tdbtool check".
      </para>
      <para>
	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.
      </para>

      <refsect3>
	<title>Example</title>
	<screen>
# ctdb getdbmap
Number of databases:10
dbid:0x435d3410 name:notify.tdb path:/var/ctdb/notify.tdb.0 
dbid:0x42fe72c5 name:locking.tdb path:/var/ctdb/locking.tdb.0
dbid:0x1421fb78 name:brlock.tdb path:/var/ctdb/brlock.tdb.0 
dbid:0x17055d90 name:connections.tdb path:/var/ctdb/connections.tdb.0 
dbid:0xc0bdde6a name:sessionid.tdb path:/var/ctdb/sessionid.tdb.0 
dbid:0x122224da name:test.tdb path:/var/ctdb/test.tdb.0 
dbid:0x2672a57f name:idmap2.tdb path:/var/ctdb/persistent/idmap2.tdb.0 PERSISTENT
dbid:0xb775fff6 name:secrets.tdb path:/var/ctdb/persistent/secrets.tdb.0 PERSISTENT
dbid:0xe98e08b6 name:group_mapping.tdb path:/var/ctdb/persistent/group_mapping.tdb.0 PERSISTENT
dbid:0x7bbbd26c name:passdb.tdb path:/var/ctdb/persistent/passdb.tdb.0 PERSISTENT

# ctdb getdbmap  # example for unhealthy database
Number of databases:1
dbid:0xb775fff6 name:secrets.tdb path:/var/ctdb/persistent/secrets.tdb.0 PERSISTENT UNHEALTHY

# ctdb -Y getdbmap
:ID:Name:Path:Persistent:Unhealthy:
:0x7bbbd26c:passdb.tdb:/var/ctdb/persistent/passdb.tdb.0:1:0:
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>
	backupdb
	<parameter>DB</parameter>
	<parameter>FILE</parameter>
      </title>
      <para>
	Copy the contents of database DB to FILE.  FILE can later be
	read back using <command>restoredb</command>.  This is mainly
	useful for backing up persistent databases such as
	<filename>secrets.tdb</filename> and similar.
      </para>
    </refsect2>

    <refsect2>
      <title>
	restoredb
	<parameter>FILE</parameter>
	<optional><parameter>DB</parameter></optional>
      </title>
      <para>
	This command restores a persistent database that was
	previously backed up using backupdb.  By default the data will
	be restored back into the same database as it was created
	from. By specifying dbname you can restore the data into a
	different database.
      </para>
    </refsect2>

    <refsect2>
      <title>getlog [<parameter>LEVEL</parameter>] [recoverd]</title>
      <para>
	In addition to the normal logging to a log file, CTDB also
	keeps a in-memory ringbuffer containing the most recent log
	entries for all log levels (except DEBUG).
      </para>
      <para>
	This is useful since it allows for keeping continuous logs to a file
	at a reasonable non-verbose level, but shortly after an incident has
	occured, a much more detailed log can be pulled from memory. This
	can allow you to avoid having to reproduce an issue due to the
	on-disk logs being of insufficient detail.
      </para>
      <para>
	This command extracts all messages of level or lower log level
	from memory and prints it to the screen.  The level is not
	specified it defaults to NOTICE.
      </para>
      <para>
	By default, logs are extracted from the main CTDB daemon.  If
	the recoverd option is given then logs are extracted from the
	recovery daemon.
      </para>
    </refsect2>

    <refsect2>
      <title>clearlog [recoverd]</title>
      <para>
	This command clears the in-memory logging ringbuffer.
      </para>
      <para>
	By default, logs are cleared in the main CTDB daemon.  If the
	recoverd option is given then logs are cleared in the recovery
	daemon.
      </para>
    </refsect2>

    <refsect2>
      <title>setdbreadonly <parameter>DB</parameter></title>
      <para>
	This command will enable the read-only record support for a
	database.  This is an experimental feature to improve
	performance for contended records primarily in locking.tdb and
	brlock.tdb.  When enabling this feature you must set it on all
	nodes in the cluster.
      </para>
    </refsect2>

    <refsect2>
      <title>setdbsticky <parameter>DB</parameter></title>
      <para>
	This command will enable the sticky record support for the
	specified database.  This is an experimental feature to
	improve performance for contended records primarily in
	locking.tdb and brlock.tdb.  When enabling this feature you
	must set it on all nodes in the cluster.
      </para>
    </refsect2>

  </refsect1>

  <refsect1>
    <title>INTERNAL COMMANDS</title>

    <para>
      Internal commands are used by CTDB's scripts and are not
      required for managing a CTDB cluster.  Their parameters and
      behaviour are subject to change.
    </para>

    <refsect2>
      <title>gettickles <parameter>IPADDR</parameter></title>
      <para>
	Show TCP connections that are registered with CTDB to be
	"tickled" if there is a failover.
      </para>
    </refsect2>

    <refsect2>
      <title>gratiousarp <parameter>IPADDR</parameter> <parameter>INTERFACE</parameter></title>
      <para>
	Send out a gratious ARP for the specified interface through
	the specified interface. This command is mainly used by the
	ctdb eventscripts.
      </para>
    </refsect2>

    <refsect2>
      <title>killtcp</title>
      <para>
	Read a list of TCP connections, one per line, from standard
	input and terminate each connection.  A connection is
	specified as:
      </para>
      <synopsis>
	<parameter>SRC-IPADDR</parameter>:<parameter>SRC-PORT</parameter> <parameter>DST-IPADDR</parameter>:<parameter>DST-PORT</parameter>
      </synopsis>
      <para>
	Each connection is terminated by issuing a TCP RST to the
	SRC-IPADDR:SRC-PORT endpoint.
      </para>
      <para>
	A single connection can be specified on the command-line
	rather than on standard input.
      </para>
    </refsect2>

    <refsect2>
      <title>
	pdelete <parameter>DB</parameter> <parameter>KEY</parameter>
      </title>
      <para>
	Delete KEY from DB.
      </para>
    </refsect2>

    <refsect2>
      <title>
	pfetch <parameter>DB</parameter> <parameter>KEY</parameter>
      </title>
      <para>
	Print the value associated with KEY in DB.
      </para>
    </refsect2>

    <refsect2>
      <title>
	pstore
	<parameter>DB</parameter>
	<parameter>KEY</parameter>
	<parameter>FILE</parameter>
      </title>
      <para>
	Store KEY in DB with contents of FILE as the associated value.
      </para>
    </refsect2>

    <refsect2>
      <title>
	ptrans
	<parameter>DB</parameter>
	<optional><parameter>FILE</parameter></optional>
      </title>
      <para>
	Read a list of key-value pairs, one per line from FILE, and
	store them in DB using a single transaction.  An empty value
	is equivalent to deleting the given key.
      </para>
      <para>
	The key and value should be separated by spaces or tabs. Each
	key/value should be a printable string enclosed in
	double-quotes.
      </para>
    </refsect2>

    <refsect2>
      <title>runstate [setup|first_recovery|startup|running]</title>
      <para>
	Print the runstate of the specified node.  Runstates are used
	to serialise important state transitions in CTDB, particularly
	during startup.
      </para>
      <para>
	If one or more optional runstate arguments are specified then
	the node must be in one of these runstates for the command to
	succeed.
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb runstate
RUNNING
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>setifacelink <parameter>IFACE</parameter> up|down</title>
      <para>
	Set the internal state of network interface IFACE.  This is
	typically used in the <filename>10.interface</filename> script
	in the "monitor" event.
      </para>
      <para>
	Example: ctdb setifacelink eth0 up
      </para>
    </refsect2>

    <refsect2>
      <title>setnatgwstate on|off</title>
      <para>
	Enable or disable the NAT gateway master capability on a node.
      </para>
    </refsect2>

    <refsect2>
      <title>tickle <parameter>SRC-IPADDR</parameter>:<parameter>SRC-PORT</parameter> <parameter>DST-IPADDR</parameter>:<parameter>DST-PORT</parameter></title>
      <para>
	Send a TCP tickle to the source host for the specified TCP
	connection.  A TCP tickle is a TCP ACK packet with an invalid
	sequence and acknowledge number and will when received by the
	source host result in it sending an immediate correct ACK back
	to the other end.
      </para>
      <para>
	TCP tickles are useful to "tickle" clients after a IP failover has
	occured since this will make the client immediately recognize the
	TCP connection has been disrupted and that the client will need
	to reestablish. This greatly speeds up the time it takes for a client
	to detect and reestablish after an IP failover in the ctdb cluster.
      </para>
    </refsect2>

    <refsect2>
      <title>version</title>
      <para>
	Display the CTDB version.
      </para>
    </refsect2>

  </refsect1>

  <refsect1>
    <title>DEBUGGING COMMANDS</title>
    <para>
      These commands are primarily used for CTDB development and testing and
      should not be used for normal administration.
    </para>


    <refsect2>
      <title>OPTIONS</title>

      <variablelist>
	<varlistentry><term>--print-emptyrecords</term>
	<listitem>
	  <para>
	    This enables printing of empty records when dumping databases
	    with the catdb, cattbd and dumpdbbackup commands. Records with
	    empty data segment are considered deleted by ctdb and cleaned
	    by the vacuuming mechanism, so this switch can come in handy for
	    debugging the vacuuming behaviour.
	  </para>
	</listitem>
	</varlistentry>

	<varlistentry><term>--print-datasize</term>
	<listitem>
	  <para>
	    This lets database dumps (catdb, cattdb, dumpdbbackup) print the
	    size of the record data instead of dumping the data contents.
	  </para>
	</listitem>
	</varlistentry>

	<varlistentry><term>--print-lmaster</term>
	<listitem>
	  <para>
	    This lets catdb print the lmaster for each record.
	  </para>
	</listitem>
	</varlistentry>

	<varlistentry><term>--print-hash</term>
	<listitem>
	  <para>
	    This lets database dumps (catdb, cattdb, dumpdbbackup) print the
	    hash for each record.
	  </para>
	</listitem>
	</varlistentry>

	<varlistentry><term>--print-recordflags</term>
	<listitem>
	  <para>
	    This lets catdb and dumpdbbackup print the
	    record flags for each record. Note that cattdb always
	    prints the flags.
	  </para>
	</listitem>
	</varlistentry>

      </variablelist>
    </refsect2>

    <refsect2>
      <title>process-exists <parameter>PID</parameter></title>
      <para>
	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.
      </para>
    </refsect2>

    <refsect2>
      <title>getdbstatus <parameter>DB</parameter></title>
      <para>
	This command displays more details about a database.
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb getdbstatus test.tdb.0
dbid: 0x122224da
name: test.tdb
path: /var/ctdb/test.tdb.0
PERSISTENT: no
HEALTH: OK

# ctdb getdbstatus registry.tdb  # with a corrupted TDB
dbid: 0xf2a58948
name: registry.tdb
path: /var/ctdb/persistent/registry.tdb.0
PERSISTENT: yes
HEALTH: NO-HEALTHY-NODES - ERROR - Backup of corrupted TDB in '/var/ctdb/persistent/registry.tdb.0.corrupted.20091208091949.0Z'
	</screen>
      </refsect3>
    </refsect2>

    <refsect2>
      <title>catdb <parameter>DB</parameter></title>
      <para>
	Print a dump of the clustered TDB database DB.
      </para>
    </refsect2>

    <refsect2>
      <title>cattdb <parameter>DB</parameter></title>
      <para>
	Print a dump of the contents of the local TDB database DB.
      </para>
    </refsect2>

    <refsect2>
      <title>dumpdbbackup <parameter>FILE</parameter></title>
      <para>
	Print a dump of the contents from database backup FILE,
	similar to <command>catdb</command>.
      </para>
    </refsect2>

    <refsect2>
      <title>wipedb <parameter>DB</parameter></title>
      <para>
	Remove all contents of database DB.
      </para>
    </refsect2>

    <refsect2>
      <title>recover</title>
      <para>
	This command will trigger the recovery daemon to do a cluster
	recovery.
      </para>
    </refsect2>

    <refsect2>
      <title>ipreallocate, sync</title>
      <para>
	This command will force the recovery master to perform a full ip reallocation process and redistribute all ip addresses. This is useful to "reset" the allocations back to its default state if they have been changed using the "moveip" command. While a "recover" will also perform this reallocation, a recovery is much more hevyweight since it will also rebuild all the databases.
      </para>
    </refsect2>

    <refsect2>
      <title>getmonmode</title>
      <para>
	This command returns the monutoring mode of a node. The monitoring mode is either ACTIVE or DISABLED. Normally a node will continuously monitor that all other nodes that are expected are in fact connected and that they respond to commands.
      </para>
      <para>
	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.
      </para>
      <para>
	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.
      </para>
    </refsect2>


    <refsect2>
      <title>setmonmode 0|1</title>
      <para>
	This command can be used to explicitly 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.
      </para>
    </refsect2>

    <refsect2>
      <title>attach <parameter>DBNAME</parameter> [persistent]</title>
      <para>
	Create a new CTDB database called DBNAME and attach to it on
	all nodes.
      </para>
    </refsect2>

    <refsect2>
      <title>detach <parameter>DB-LIST</parameter></title>
      <para>
	Detach specified non-persistent database(s) from the cluster. This
	command will disconnect specified database(s) on all nodes in
	the cluster.  This command should only be used when none of the
	specified database(s) are in use.
      </para>
      <para>
	All nodes should be active and tunable AllowClientDBAccess should
	be disabled on all nodes before detaching databases.
      </para>
    </refsect2>

    <refsect2>
      <title>dumpmemory</title>
      <para>
	This is a debugging command. This command will make the ctdb
	daemon to write a fill memory allocation map to standard output.
      </para>
    </refsect2>

    <refsect2>
      <title>rddumpmemory</title>
      <para>
	This is a debugging command. This command will dump the talloc memory
	allocation tree for the recovery daemon to standard output.
      </para>
    </refsect2>

    <refsect2>
      <title>thaw</title>
      <para>
	Thaw a previously frozen node.
      </para>
    </refsect2>


    <refsect2>
      <title>eventscript <parameter>ARGUMENTS</parameter></title>
      <para>
	This is a debugging command. This command can be used to manually
	invoke and run the eventscritps with arbitrary arguments.
      </para>
    </refsect2>

    <refsect2>
      <title>ban <parameter>BANTIME</parameter></title>
      <para>
	Administratively ban a node for BANTIME seconds.  The node
	will be unbanned after BANTIME seconds have elapsed.
      </para>
      <para>
	A banned node does not participate in the cluster.  It does
	not host any records for the clustered TDB and does not host
	any public IP addresses.
      </para>
      <para>
	Nodes are automatically banned if they misbehave.  For
	example, a node may be banned if it causes too many cluster
	recoveries.
      </para>
      <para>
	To administratively exclude a node from a cluster use the
	<command>stop</command> command.
      </para>
    </refsect2>

    <refsect2>
      <title>unban</title>
      <para>
	This command is used to unban a node that has either been
	administratively banned using the ban command or has been
	automatically banned.
      </para>
    </refsect2>

    <refsect2>
      <title>
	rebalancenode
	<optional><parameter>PNN-LIST</parameter></optional>
      </title>
      <para>
	This command marks the given nodes as rebalance targets in the
	LCP2 IP allocation algorithm.  The
	<command>reloadips</command> command will do this as necessary
	so this command should not be needed.
      </para>
    </refsect2>

    <refsect2>
      <title>check_srvids <parameter>SRVID</parameter> ...</title>
      <para>
	This command checks whether a set of srvid message ports are
	registered on the node or not. The command takes a list of
	values to check.
      </para>
      <refsect3>
	<title>Example</title>
	<screen>
# ctdb check_srvids 1 2 3 14765
Server id 0:1 does not exist
Server id 0:2 does not exist
Server id 0:3 does not exist
Server id 0:14765 exists
	</screen>
      </refsect3>
    </refsect2>

  </refsect1>

  <!-- UNDOCUMENTED: showban stats disablemonitor enablemonitor
       isnotrecmaster addtickle deltickle regsrvid unregsrvid chksrvid
       getsrvids rebalanceip setdbprio getdbprio msglisten msgsend
       tfetch tstore readkey writekey
       checktcpport getdbseqnum ipiface
  -->

  <refsect1>
    <title>SEE ALSO</title>
    <para>
      <citerefentry><refentrytitle>ctdbd</refentrytitle>
      <manvolnum>1</manvolnum></citerefentry>,

      <citerefentry><refentrytitle>onnode</refentrytitle>
      <manvolnum>1</manvolnum></citerefentry>,

      <citerefentry><refentrytitle>ctdb</refentrytitle>
      <manvolnum>7</manvolnum></citerefentry>,

      <citerefentry><refentrytitle>ctdb-tunables</refentrytitle>
      <manvolnum>7</manvolnum></citerefentry>,

      <ulink url="http://ctdb.samba.org/"/>
    </para>
  </refsect1>


</refentry>