Creating a cluster with a single VIOS logical partition

You can create a cluster with a single VIOS logical partition by using the VIOS command-line interface.

Before you start, ensure that the following requirements are satisfied:

Log in to the viosA1 VIOS logical partition by using the padmin user ID, which provides a restricted Korn shell environment.
Locate the physical volumes to be used for the clusterA cluster. For example, entering the lspv -free command returns results similar to the following:
```
NAME      PVID                    SIZE (megabytes)
-------------------------------------------------------
hdisk0    none                     17408
hdisk2    000d44516400a5c2         20480
hdisk3    000d4451605a0d99         20482
hdisk4    none                     10250
hdisk5    none                     20485
hdisk6    none                     20490
hdisk7    none                     20495
hdisk8    none                     20500
hdisk9    none                     20505
```
The lspv command displays a list of physical volumes along with the ID. The physical volume ID indicates that the device might be in use. The system administrator must ensure that the physical volume is not in use before adding it to the cluster repository or shared storage pool. For example, you can select the hdisk9 physical volume for the repository, and hdisk5 and hdisk7 physical volumes for the storage pool.

To create a cluster with one VIOS logical partition, complete the following steps:

Run the cluster command to create the cluster. In the following example, the storage pool for the clusterA cluster is named poolA.
```
cluster -create -clustername clusterA -repopvs hdisk9 -spname poolA -sppvs  hdisk5  hdisk7 -hostname
viosA1_HostName
```

After you create the cluster, run the lspv command to display the list of all the physical volumes visible to the logical partition. For example, entering the lspv command returns results similar to the following:

NAME          PVID                    VG                   STATUS
---------------------------------------------------------------------
hdisk0        none                     None					       
hdisk1        000d4451b445ccc7         rootvg              active
hdisk2        000d44516400a5c2         20480					     
hdisk3        000d4451605a0d99         10250					     
hdisk4        none                     20485					     
hdisk5        none                     20490					     
hdisk6        none                     20495					     
hdisk7        none                     20500					     
hdisk8        none                     20505					     
hdisk9        none                     caavg_private       active

Note: The disk for the repository has a volume group name caavg_private. Volume group commands such as exportvg and lsvg must not be run on the repository disk.

To display a list of physical volumes for which the usage cannot be determined, run the lspv command. For example, entering the lspv -free command returns results similar to the following:

NAME      PVID                    SIZE (megabytes)
-------------------------------------------------------
hdisk0    none                     17408
hdisk2    000d44516400a5c2         20480
hdisk3    000d4451605a0d99         20482
hdisk4    none                     10250
hdisk6    none                     20490
hdisk8    none                     20500

To display the physical volumes in the storage pool, run the lspv command. For example, entering the lspv -clustername clusterA -sp poolA command returns results similar to the following:

PV NAME      SIZE(MB)  	  	 PVUDID   
-------------------------------------------------------
hdisk5       20480         200B75CXHW1026D07210790003IBMfcp        
hdisk7       20495         200B75CXHW1020207210790003IBMfcp

To display cluster information, run the cluster command. For example, entering the cluster -status -clustername clusterA command returns results similar to the following:

Cluster Name         State
clusterA             OK

    Node Name        MTM           Partition Num  State  Pool State
    viosA1           9117-MMA0206AB272        15  OK     OK

To list cluster configuration information, use the lscluster command. For example, entering the lscluster -m command returns results similar to the following:

Calling node query for all nodes
Node query number of nodes examined: 1

Node name: viosA1
Cluster shorthand id for node: 1
uuid for node: ff8dd204-2de1-11e0-beef-00145eb8a94c
State of node:  UP  NODE_LOCAL
Smoothed rtt to node: 0
Mean Deviation in network rtt to node: 0
Number of zones this node is a member in: 0
Number of clusters node is a member in: 1
CLUSTER NAME       TYPE  SHID   UUID
clusterA           local        a3fe209a-4959-11e0-809c-00145eb8a94c
Number of points_of_contact for node: 0
Point-of-contact interface & contact state
n/a

For more information, see lscluster command.

Last updated: Thu, October 15, 2020