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mmcrcluster Command
Name
mmcrcluster – Creates a GPFS cluster from a set of nodes.
Synopsis
mmcrcluster -N {NodeDesc[,NodeDesc...] | NodeFile} -p PrimaryServer [-s SecondaryServer] [-r
RemoteShellCommand] [-R RemoteFileCopyCommand] [-C ClusterName] [-U DomainName] [-A] [-c
ConfigFile]
Description
Use the mmcrcluster command to create a GPFS cluster.
Upon successful completion of the mmcrcluster command, the /var/mmfs/gen/mmsdrfs and the
/var/mmfs/gen/mmfsNodeData files are created on each of the nodes in the cluster. Do not delete these
files under any circumstances. For further information, see the General Parallel File System: Concepts,
Planning, and Installation Guide.
You must follow these rules when creating your GPFS cluster:
v While a node may mount file systems from multiple clusters, the node itself may only be added to a
single cluster using the mmcrcluster or mmaddnode command.
v The nodes must be available for the command to be successful. If any of the nodes listed are not
available when the command is issued, a message listing those nodes is displayed. You must correct
the problem on each node and issue the mmaddnode command to add those nodes.
v You must designate at least one node as a quorum node. You are strongly advised to designate the
cluster configuration servers as quorum nodes. How many quorum nodes altogether you will have
depends on whether you intend to use the node quorum with tiebreaker algorithm. or the regular node
based quorum algorithm. For more details, see the General Parallel File System: Concepts, Planning,
and Installation Guide and search for designating quorum nodes.
Parameters
-A Specifies that GPFS daemons are to be automatically started when nodes come up. The default is
not to start daemons automatically.
-C ClusterName
Specifies a name for the cluster. If the user-provided name contains dots, it is assumed to be a
fully qualified domain name. Otherwise, to make the cluster name unique, the domain of the
primary configuration server will be appended to the user-provided name.
If the -C flag is omitted, the cluster name defaults to the name of the primary GPFS cluster
configuration server.
-c ConfigFile
Specifies a file containing GPFS configuration parameters with values different than the
documented defaults. A sample file can be found in /usr/lpp/mmfs/samples/mmfs.cfg.sample.
See the mmchconfig command for a detailed description of the different configuration
parameters.
The -c ConfigFile parameter should be used only by experienced administrators. Use this file to
set up only those parameters that appear in the mmfs.cfg.sample file. Changes to any other
values may be ignored by GPFS. When in doubt, use the mmchconfig command instead.
-N NodeDesc[,NodeDesc...] | NodeFile
NodeFile specifies the file containing the list of node descriptors (see below), one per line, to be
included in the GPFS cluster.
114 GPFS: Administration and Programming Reference