mmchcluster command

Availability

Available on all IBM Storage Scale editions.

Description

To display current system information for the cluster, issue the mmlscluster command.

For information on how to specify node names, see Specifying nodes as input to GPFS commands.

Parameters

-r RemoteShellCommand

Specifies the fully-qualified path name for the remote shell program to be used by GPFS.

The remote shell command must adhere to the same syntax format as the ssh command, but may implement an alternate authentication mechanism.

-R RemoteFileCopy

Specifies the fully-qualified path name for the remote file copy program to be used by GPFS.

The remote copy command must adhere to the same syntax format as the scp command, but may implement an alternate authentication mechanism.

--nouse-sudo-wrapper

Specifies that the cluster reverts to using the default remote shell program and remote copy program. For more information, see Running IBM Storage Scale commands without remote root login.

--use-sudo-wrapper [sudo-user UserName]

Causes the nodes in the cluster to call the ssh and scp sudo wrapper scripts as the remote shell program and the remote copy program. For more information, see Running IBM Storage Scale commands without remote root login.

--sudo-user UserName

Specifies a non-root admin user ID to be used when sudo wrappers are enabled and a root-level background process calls an administration command directly instead of through sudo. The GPFS daemon that processes the administration command specifies this non-root user ID instead of the root ID when it needs to run internal commands on other nodes. For more information, see Root-level processes that call administration commands directly.

To disable this feature, specify the key word DELETE instead of a user name, as in the following example:

# mmchcluster --sudo-user DELETE

--scaleadm-remote

Specifies the use of the IBM Storage Scale native REST API remote shell and copy services. This option is equivalent to specifying the following options at the same time:

• -r {scaleadmremote | scaleadmremoteexecute}
• -R {scaleadmremote | scaleadmremotetransfer}

-C ClusterName

Specifies a new name for the cluster. If the user-provided name contains dots then the command assumes that the user-provided name is a fully qualified domain name. Otherwise, to make the cluster name unique, the command appends the domain of a quorum node to the user-provided name. The maximum length of the cluster name including any appended domain name is 115 characters.

Since each cluster is managed independently, there is no automatic coordination and propagation of changes between clusters like there is between the nodes within a cluster. This means that if you change the name of the cluster, you should notify the administrators of all other GPFS clusters that can mount your file systems so that they can update their own environments.

Before running this option, ensure that all GPFS daemons on all nodes have been stopped.

See the mmauth, mmremotecluster, and mmremotefs commands.

Exit status

0

Successful completion.

nonzero

A failure has occurred.

Security

You must have root authority to run the mmchcluster command.

The node on which the command is issued must be able to run remote shell commands on any other node in the cluster without the use of a password and without producing any extraneous messages. For more information, see Requirements for administering a GPFS file system.

See also

Location