Provided by: cman_1.20060222-0ubuntu5_i386
cman - cluster.conf cman configuration section
Cman configuration values are placed in the <cman> </cman> section of
cluster.conf. Per-node configuration related to cman is placed in the
standard <clusternode> </clusternode> sections. All cman configuration
settings are optional; usually none are used.
By default, cman will use UDP port 6809 for internode communication.
This can be changed by setting a port number as follows:
The expected votes value is used by cman to determine quorum. The
cluster is quorate if the sum of votes of existing members is over half
of the expected votes value. By default, cman_tool sets the expected
votes value to be the sum of votes of all nodes listed in cluster.conf.
This can be overriden by setting an explicit expected_votes value as
If the cluster becomes partitioned, improper use of this option can
result in more than one partition gaining quorum. In that event, nodes
in each partition will enable cluster services.
Two node clusters
Ordinarily, the loss of quorum after one out of two nodes fails will
prevent the remaining node from continuing (if both nodes have one
vote.) Special configuration options can be set to allow the one
remaining node to continue operating if the other fails. To do this
only two nodes, each with one vote, can be defined in cluster.conf.
The two_node and expected_votes values must then be set to 1 in the
cman section as follows.
<cman two_node="1" expected_votes="1">
By default, a node is given one vote toward the calculation of quorum.
This can be changed by giving a node a specific number of votes as
<clusternode name="nd1" votes="2">
By default, a node is assigned a nodeid by the cluster manager (cman)
when it joins the cluster. This can be overriden by specifying a
nodeid here. Using this option will ensure that a given node always
has the same ID. A node’s application to join the cluster may be
rejected if you try to set the nodeid to one that is already used.
<clusternode name="nd1" nodeid="1">
Multicast network configuration
Cman can be configured to use multicast instead of broadcast (broadcast
is used by default if no multicast parameters are given.) To configure
multicast add one line under the <cman> section and another under the
<multicast addr="188.8.131.52" interface="eth0"/>
The multicast addresses must match and the address must be usable on
the interface name given for the node.
cluster.conf(5), ccs(7), cman_tool(8)