I'm doing the VILT "VNX Unified Storage Infrastructure Solution" and found the following statement about a SnapView snapshot:
The SnapView snapshot can be made accessible to a secondary host, but not to the primary host (unless software that allows simultaneous access, like EMC Replication Manager, is used).
I' asking me why it should not be possible to access the snapshot from the primary host.
Both the Source LUN as well as the snapshot are presentet as a LUN to the host with different SCSI addresses.
But I don't find any answer for that. Does anybody has an explanation?
Here's an answer from @andre.rossouw
"Many hosts write a unique signature to each LUN/volume that they access. When a Snapshot is made of such a volume, the signature of the snapshot is identical to that of the source volume. If both are assigned to the same host, and the host doesn’t have a graceful method of resolving duplicate signatures [as VMware does, for example, by resignaturing the snapshot], there could be issues with the host. The issue would be similar to what we’d see if we presented a LUN to a host across multiple paths, but had no multipathing software active."