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<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>ctdbd</title><meta name="generator" content="DocBook XSL Stylesheets V1.72.0"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en"><a name="ctdbd.1"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>ctdbd — The CTDB cluster daemon</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><div class="cmdsynopsis"><p><code class="command">ctdbd</code> </p></div><div class="cmdsynopsis"><p><code class="command">ctdbd</code> {--reclock=<filename>} {--nlist=<filename>} {--dbdir=<directory>} [-? --help] [--usage] [-i --interactive] [--public-addresses=<filename>] [--public-interface=<interface>] [--event-script=<filename>] [--logfile=<filename>] [--listen=<address>] [--transport=<STRING>] [--socket=<filename>] [-d --debug=<INTEGER>] [--torture]</p></div></div><div class="refsect1" lang="en"><a name="id2488930"></a><h2>DESCRIPTION</h2><p>
ctdbd is the main ctdb daemon.
</p><p>
ctdbd provides a clustered version of the TDB database with automatic rebuild/recovery of the databases upon nodefailures.
</p><p>
Combined with a cluster filesystem ctdbd provides a full HA environment for services such as clustered Samba and NFS as well as other services.
</p><p>
ctdbd provides monitoring of all nodes in the cluster and automatically reconfigures the cluster and recovers upon node failures.
</p><p>
ctdbd is the main component in clustered Samba that provides a high-awailability load-sharing CIFS server cluster.
</p></div><div class="refsect1" lang="en"><a name="id2488962"></a><h2>OPTIONS</h2><div class="variablelist"><dl><dt><span class="term">-? --help</span></dt><dd><p>
Print some help text to the screen.
</p></dd><dt><span class="term">--usage</span></dt><dd><p>
Print useage information to the screen.
</p></dd><dt><span class="term">--reclock=<filename></span></dt><dd><p>
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.
This file must be stored on shared storage.
</p></dd><dt><span class="term">--nlist=<filename></span></dt><dd><p>
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.
</p><p>
This file is usually /etc/ctdb/nodes .
</p></dd><dt><span class="term">--dbdir=<directory></span></dt><dd><p>
This is the directory on local storage where ctdbd keeps the local
copy of the TDB databases. This directory is local for each node and should not be stored on the shared cluster filesystem.
</p><p>
This directory would usually be /var/ctdb .
</p></dd><dt><span class="term">-i --interactive</span></dt><dd><p>
By default ctdbd will detach itself from the shell and run in
the background as a daemon. This option makes ctdbd to start in interactive mode.
</p></dd><dt><span class="term">--public_addresses=<filename></span></dt><dd><p>
When used with IP takeover this specifies a file containing the public ip addresses to use on the cluster. This file contains one entry for each node in the cluster.
</p><p>
This is usually the file /etc/ctdb/public_addresses
</p></dd><dt><span class="term">--public-interface=<interface></span></dt><dd><p>
When used with IP takeover this option specifies which physical interface should be used to attach the public addresses to.
</p></dd><dt><span class="term">--event-script=<filename></span></dt><dd><p>
This option is used to specify which events script that ctdbd will
use to manage services when the cluster configuration changes.
</p><p>
This will normally be /etc/ctdb/events which is part of the ctdb distribution.
</p></dd><dt><span class="term">--logfile=<filename></span></dt><dd><p>
This is the file where ctdbd will write its log. This is usually /var/log/log.ctdb .
</p></dd><dt><span class="term">--listen=<address></span></dt><dd><p>
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.
</p><p>
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.
</p></dd><dt><span class="term">--transport=<STRING></span></dt><dd><p>
This option specifies which transport to use for ctdbd internode communications. The default is "tcp".
</p><p>
Suported transports are "tcp" and "infiniband".
</p></dd><dt><span class="term">--socket=<filename></span></dt><dd><p>
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.
</p><p>
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.
</p></dd><dt><span class="term">-d --debug=<DEBUGLEVEL></span></dt><dd><p>
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.
</p></dd><dt><span class="term">--torture</span></dt><dd><p>
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.
</p><p>
You do NOT want to use this option unless you are developing and testing new functionality in ctdbd.
</p></dd></dl></div></div><div class="refsect1" lang="en"><a name="id2490376"></a><h2>Private vs Public addresses</h2><p>
When used for ip takeover in a HA environment, each node in a ctdb
cluster has two ip addresses assigned to it. One private and one public.
</p><div class="refsect2" lang="en"><a name="id2490386"></a><h3>Private address</h3><p>
This is the physical ip address of the node which is configured in
linux and attached to a physical interface. This address uniquely
identifies a physical node in the cluster and is the ip addresses
that ctdbd will use to communicate with the ctdbd daemons on the
other nodes in the cluster.
</p><p>
The private addresses are configured in /etc/ctdb/nodes
(unless the --nlist option is used) and contain one line for each
node in the cluster. Each line contains the private ip address for one
node in the cluster.
</p><p>
Each node is assigned an internal node number which corresponds to
which line in the nodes file that has the local private address
of the node.
</p><p>
Since the private addresses are only available to the network when the
corresponding node is up and running you should not use these addresses
for clients to connect to services provided by the cluster. Instead
client applications should only attach to the public addresses since
these are guaranteed to always be available.
</p>
Example /etc/ctdb/nodes for a four node cluster:
<pre class="screen">
10.1.1.1
10.1.1.2
10.1.1.3
10.1.1.4
</pre></div><div class="refsect2" lang="en"><a name="id2490432"></a><h3>Public address</h3><p>
A public address on the other hand is not attached to an interface.
This address is managed by ctdbd itself and is attached/detached to
a physical node at runtime. You should NOT have this address configured
to an interface in linux. Let ctdbd manage these addresses.
</p><p>
The ctdb cluster will assign/reassign these public addresses across the
available nodes in the cluster. When one node fails, its public address
will be migrated to and taken over by a different node in the cluster
to ensure that all public addresses are always available to clients.
</p><p>
These addresses are not physically attached to a specific node.
The 'ctdb ip' command can be used to view the current assignment of
public addresses and which physical node is currently serving it.
</p><p>
By default, each node will when operational always serve its primary
public address which is the corresponding line for that node number
in the public addresses file. I.e. as long as node X is available and
fully oprational it will always be the node that serves the
corresponding public address.
</p><p>
The list of public addresses also contain the netmask for that address.
the reason for this is because ctdbd needs to know which mask to use
when it adds/removes the address from a physical node. This netmask
is also used by ctdbd when making decisions on which node should take
over a public ip address for a failed node.
A node will only be allowed to take over a public address from a
different node IFF that public address resides in the same subnet
as the primary public address for that node.
</p>
Example /etc/ctdb/public_addresses for a four node cluster:
<pre class="screen">
11.1.1.1/24
11.1.1.2/24
11.1.2.1/24
11.1.2.2/24
</pre><p>
In this example, if node 3 fails, its public address can be taken over
by node 2 since node 2 is on the same subnet as 3 but not by node 0 or
node 1 since node 0 and 1 are both on a different subnet from node 3.
</p></div></div><div class="refsect1" lang="en"><a name="id2536612"></a><h2>Node status</h2><p>
The current status of each node in the cluster can be viewed by the
'ctdb status' command.
</p><p>
There are five possible for a node.
</p><p>
OK - This node is fully functional.
</p><p>
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.
</p><p>
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.
</p><p>
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 currently being hosted. All unhealthy nodes
should be investigated and require an administrative action to rectify.
</p><p>
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.
</p></div><div class="refsect1" lang="en"><a name="id2536669"></a><h2>SEE ALSO</h2><p>
ctdb(1), onnode(1)
<a href="http://ctdb.samba.org/" target="_top">http://ctdb.samba.org/</a>
</p></div><div class="refsect1" lang="en"><a name="id2536682"></a><h2>COPYRIGHT/LICENSE</h2><div class="literallayout"><p><br>
Copyright (C) Andrew Tridgell 2007<br>
Copyright (C) Ronnie sahlberg 2007<br>
<br>
This program is free software; you can redistribute it and/or modify<br>
it under the terms of the GNU General Public License as published by<br>
the Free Software Foundation; either version 3 of the License, or (at<br>
your option) any later version.<br>
<br>
This program is distributed in the hope that it will be useful, but<br>
WITHOUT ANY WARRANTY; without even the implied warranty of<br>
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU<br>
General Public License for more details.<br>
<br>
You should have received a copy of the GNU General Public License<br>
along with this program; if not, see http://www.gnu.org/licenses/.<br>
</p></div></div></div></body></html>
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