Storage Replication Adapter: What determines if a new initiator group or export policy is created during a failover operation?

Applies to

• ONTAP Tools for VMware vSphere (OTV)
• Storage Replication Adapter (SRA)
• VMware Site Recovery Manager (SRM)

Answer

1. During a failover operation, VMware Site Recovery Manager (SRM) will compile a list of initiators from ESXi hosts on the disaster recovery (DR) site. From SRM logging:

2016-07-22T13:16:30.626-04:00 [04464 verbose 'Storage' opID=] Retrieved VM Kernel IP address
'192.168.0.101' for host 'vim.HostSystem:xxx'
2016-07-22T13:16:30.626-04:00 [04464 verbose 'Storage' opID=] Retrieved VM Kernel IP address
'192.168.0.102' for host 'vim.HostSystem:xxx'
2016-07-22T13:16:30.626-04:00 [04464 verbose 'Storage' opID=] Retrieved VM Kernel IP address
'192.168.0.103' for host 'vim.HostSystem:xxx'
2016-07-22T13:16:30.626-04:00 [04464 verbose 'Storage' opID=] Retrieved FC HBA 'vmhba1' for host 'vim.HostSystem:xxx'
2016-07-22T13:16:30.626-04:00 [04464 verbose 'Storage' opID=] Retrieved FC HBA 'vmhba2' for host 'vim.HostSystem:xxx'
2016-07-22T13:16:30.626-04:00 [04464 verbose 'Storage' opID=] Retrieved FC HBA 'vmhba1' for host 'vim.HostSystem:xxx'
2016-07-22T13:16:30.626-04:00 [04464 verbose 'Storage' opID=] Retrieved FC HBA 'vmhba2' for host 'vim.HostSystem:xxx'

2. SRM will compile these initiators into an 'access group':

2016-07-22T13:16:30.626-04:00 [04464 verbose 'Storage' opID=] Added
initiators to access group 'domain-***':
--> [{FC: 20:00:00:***}, {FC: 20:00:00:*****}, {FC: 20:00:00:*****},
{FC: 20:00:00:*****}, {FC: 20:00:00:*****}, {FC: 20:00:00:*****}, {FC:
{NFS:****}, {NFS: ****}, {NFS: ****}, 

3. SRM will then pass this 'access group' to Storage Replication Adapter (SRA) prior to the failover operation:

--> <AccessGroups>
--> <AccessGroup id="domain-c91">
--> <Initiator id="20:00:00:*****" type="FC"/>
--> <Initiator id="20:00:00:*****" type="FC"/>
--> <Initiator id="****" type="NFS"/>
--> <Initiator id="****" type="NFS"/>
--> </AccessGroup>
--> </AccessGroups>

4. SRA  determines if there is an existing initiator group (for SAN) or an existing export policy (for NFS) on the storage array at the DR site
   • If the initiators that were provided by SRM in the access group match the initiators in a existing igroup or the rules in a existing export policy, the existing igroup or policy will be used
   • If the initiators that were provided by SRM in the access group do not match the initiators in a existing igroup or the rules in a existing export policy, a new igroup or export policy will be created
     • SRA will create a test_failover igroup for any test failover performed by SRM

Note: SRA is dependent upon SRM to provide a list of initiators.  SRA simply processes the access group that SRM provides and determines if a new igroup or policy needs to be created or whether an existing igroup or policy can be used.  For more information regarding how SRM constructs a access group please see VMware KB 83335

Additional Information