Provided by: cman_1.20060222-0ubuntu5_i386 bug

NAME

       cman - cluster.conf cman configuration section

DESCRIPTION

       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.

UDP port
       By default, cman will use UDP port 6809  for  internode  communication.
       This can be changed by setting a port number as follows:

         <cman port="6809">
         </cman>

Expected votes
       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
       follows:

         <cman expected_votes="3">
         </cman>

       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">
         </cman>

Node votes
       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
       follows:

         <clusternode name="nd1" votes="2">
         </clusternode>

Node ID

       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">
         </clusternode>

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
       <clusternode> section:

         <cman>
             <multicast addr="224.0.0.1"/>
         </cman>

         <clusternode name="nd1">
             <multicast addr="224.0.0.1" interface="eth0"/>
         </clusternode>

       The  multicast  addresses  must match and the address must be usable on
       the interface name given for the node.

SEE ALSO

       cluster.conf(5), ccs(7), cman_tool(8)

                                                                       cman(5)