I was at a customer site helping out configuring SRM yesterday. During the configuration of the EMC SRDF SRA(Storage Replication Adapter) we ran into a weird issue. Although we could see the paired arrays with a green “okay sign” we did not see any replicated LUNs. First things I usually check in these cases are:
- Is the LUN already formatted as VMFS
- Does it hold any VMs
In this case we met both requirements. After checking all the configuration settings on the SRA side, SRM side and the SAN we noticed that the SPC-2 bit was not enabled. Of course we knew that is was a required setting according to the FC San Config Guide(page 57) but this is definitely not the kind of behavior I would expect to see when it’s disabled. Anyway I did a quick search on our internal mailing list and as it appears we were not the first to encounter these issues.
The SPC-2 bit is something that comes up every now and then, so if you’ve got EMC Symmetrix storage and you are not sure whether you have applied VMware’s recommendations please read the FC San Config Guide and avoid future problems. Please bare in mind though that when you set the SPC-2 bit you might and probably will need to re-signature the disk.