Heartbeating over disk

You can configure a disk heartbeat optionally. After configuration, the Reliable Scalable Cluster Technology (RSCT) automatically exchanges heartbeat over the shared disk. These connections can provide an alternative heartbeat path for a cluster that uses a single TCP/IP-based network.

You can configure a disk heartbeat by using following command:

clmgr add network netw_0 TYPE=disk 
pvid=qoPDC7-G169-UJv3-zHI5-KePI-Whjy-K73nrb 
nodes= nodeA, nodeB

Once the disk heartbeat configuration is complete, you can verify by using following command:

clmgr query network netw_0

To check whether the heartbeat interface is properly functioning, run the following command:

lssrc -ls cthats

The following output is generated:


Subsystem               Group            PID     	Status
cthats           	 cthats           372762 	 active

Network Name   Indx  Defd         Mbrs   St      Adapter ID            Group ID
dhbTEST_CG     [1]   2     	 2      S      255.255.10.1    	255.255.10.1
dhbTEST_CG     [1]   dhb-1-2          	    0x01c8f4fe      	0x01c8f511

In the specified sample command output, find the disk heartbeat stanza by locating the name of the disk heartbeat network, which is obtained by using the clmgr query network command output. The name of the disk heartbeat interface resource is also displayed.

Positive result: Disk heartbeat is occurring if the Defd and Mbrs parameters are the same number:

 
Defd Mbrs
2    2

Negative or error result: Disk heartbeat is not occurring if the Defd and Mbrs parameters are different:

 
Defd Mbrs
2    1

If you get negative or error result for the disk heartbeat process, recheck the following options:

Port VLAN ID (PVID) on which disk heartbeat network is configured is available on both the cluster nodes.
Storage connectivity with both the cluster nodes is working.
Physical volume on which disk heartbeat is configured is not being used by any other process, which might block the IO on the device.

To remove the existing heartbeat network, enter the following command:

clmgr delete network netw_0

To modify an existing heartbeat network, enter the following command:

clmgr modify network netw_0 node=nodeA, nodeB, nodeC

Where, the node parameter lists the node that must be modified. PowerHA SystemMirror supports disk heartbeat for a four-node cluster. end of change

start of change You can use the clmgr modify network command only for the disk type of network. end of change