7.6 Creating the GPFS nodeset

---

7.6 Creating the GPFS nodeset

You may have different nodesets within the GPFS cluster. A nodeset is a group of some or all of the GPFS nodes in a cluster, but all GPFS nodes must be in the cluster definition, and a node must be in one nodeset only.

The mmconfig command is responsible for creating the nodeset. The file containing the nodes in this nodeset is defined with the -n <nodename> parameter or -a for all nodes.

The following optional parameters can be also used:

-C	Defines the name of the nodeset. If not specified, GPFS assigns an integer as the nodeset name: 1, 2, 3, and so on.
-M	Specifies the amount of files to be cached. The default value is 1000.
-p	The size of the cache on each node. The pagepool default value is 20 MB.
-P	The communication protocol to be used for inter-node communication. Valid values are TCP and LAPI. The default is TCP.
-A	Sets the nodes to start the GPFS daemons at boot time.
-D	GPFS can generate dumps in case of problems in the file systems in the nodeset. This option will define the location of those dump files. The default value is /tmp/mmfs.

When we defined the nodeset in our lab, we did not define any name for the nodeset and will take the default name GPFS would assign to the cluster, which is 1, and will take the rest of parameter as the default, as shown in Example 7-22 on page 211.

Example 7-22: mmconfig command

 [root@storage001 root]# mmconfig -aA mmconfig: Command successfully completed mmconfig: Propagating the changes to all affected nodes. This is an asynchronous process. [root@storage001 root]# 

After issuing the mmconfig command, you can verify the nodeset definitions using the mmlsconfig command with the unique -C defining the name of the nodeset; if no nodeset name is specified, or if you specify . (dot) as the name of the nodeset (-C .), the mmlsconfig command will display the configuration for nodeset to which the node executing the command belongs (this is valid for all commands that have the -C parameter). The output of the mmlsconfig command can be seen in Example 7-23.

Example 7-23: mmlsconfig command

 [root@storage001 root]# mmlsconfig Configuration data for nodeset 1: --------------------------------- clusterType lc comm_protocol TCP multinode yes autoload yes useSingleNodeQuorum no group Gpfs.1 recgroup GpfsRec.1 File systems in nodeset 1: -------------------------- (none) [root@storage001 root]# 

---