For a storage upgrade, I swapped out two HBAs, an SAS9341-8i (SAS3) and a Dell PERC H310 (SAS2). The 9341 was changed to a 9300-8i and the PERC was replaced with another 9300-8i.
The storage was acting as iSCSI targets for two ESXi datastores. For the LUN originally attached to the SAS2 card, the device could be seen in ESXi (under storage->devices) however the datastore would not mount. The datastore that was originally on the 9341 card was fine.
ESXi logs (monitor -> logs -> /var/log/vmkernel.log) showed that the device was “detected to be a snapshot.” VMware has as KB describing this problem where ESXi cannot confirm the identity of the LUN attached to the new SAS3 adapter.
The steps used to fix the datastore that would not mount:
- Find the device
esxcli storage vmfs snapshot list
- Resignature the device and mount
esxcli storage vmfs snapshot resignature -l “LABEL OF THE VMFS”
- Check ESXi datastores (Storage-> datastores)
You should see it appear with a new name “snap-xxxx-LABEL OF THE VMFS”
- Rename the datastore as appropriate
Notes: Registered VMs on that datastore had to be reregistered. Also VMs that used hard drives on that datastore had to updated in the configuration for the new signature.