Link between Site A and Mediator down and Site B down

12/04/2020 Download PDF of this page

Determining the cause:

Check the status of Mediator from Site A.

Example:

C1_cluster::*> snapmirror mediator show
Mediator Address Peer Cluster     Connection Status Quorum Status
---------------- ---------------- ----------------- -------------
10.237.86.17     C2_cluster       unreachable       true

C1_cluster::*> snapmirror list-destinations
                                                  Progress
Source             Destination         Transfer   Last         Relationship
Path         Type  Path         Status Progress   Updated      Id
----------- ----- ------------ ------- --------- ------------ ---------------
vs0:/cg/src_cg_1  XDP   vs1:/cg/dst_cg_1  OutOfSync  -         -            bba7d354-06f6-11eb-9138-005056acec19

Check Site B connectivity:

C1_sti78-vsim-ucs188a_cluster::*> cluster peer show
Peer Cluster Name         Cluster Serial Number Availability   Authentication
------------------------- --------------------- -------------- --------------
C2_cluster                1-80-000011           Unavailable    ok

Check the consensus status on SM-BC volume:

C1_cluster::*> volume show zrto_cg_894191_188b_RW1 -fields smbc-consensus
vserver volume                  smbc-consensus
------- ----------------------- ------------------
vs0     zrto_cg_894191_188b_RW1 Awaiting-consensus

Solution:

Complete the following steps to override SM-BC consensus and forcefully resume I/O on Site A:

Unmap the LUNs on Site A.
Issue the snapmirror release command using the -force and override-smbc-consensus option on Site A.
Remap the LUNs.
First, bring up Mediator, and then bring up the Site B nodes.
Resync the consistency group relationship using snapmirror resync.
After Site B is up, verify that the consistency group relationship is up and is in sync.
Perform a LUN rescan on the host to restore all paths to the LUNs.