If you accidentally mask a boot device, the /bootbank partition on your ESXi system might become unavailable. The /bootbank partition contains core hypervisor code and is critical for the functioning of the ESXi system. If the partition becomes unavailable, your system might experience serious performance problems and fail.
You may see the error: Bootbank cannot be found at path Path_to_bootbank
Use the vSphere CLI to unmask the paths to the boot device.
Use the esxcfg-scsidevs -a command to determine which adapter is used for the boot device.
Run the following command to obtain a list of all claim rules for the boot device adapter. The following example uses vmhba1 adapter:
# esxcli corestorage claimrule list|grep vmhba1
In the list, locate the MASK_PATH claim rules, which look similar to the following:
MP 148 runtime location MASK_PATH adapter=vmhba1 channel=0 target=0 lun=0
MP 148 file location MASK_PATH adapter=vmhba1 channel=0 target=0 lun=0
MP 149 runtime location MASK_PATH adapter=vmhba1 channel=0 target=0 lun=0
MP 149 file location MASK_PATH adapter=vmhba1 channel=0 target=0 lun=0
Delete the MASK_PATH claim rules by running the following command sequence. Make sure to change numbers 148 and 149 in the following sample commands based on the output of the command in step 2:
# esxcli corestorage claimrule delete -r 148
# esxcli corestorage claimrule delete -r 149
# esxcli corestorage claimrule load
# esxcli corestorage claimrule run
Unmask the paths for the boot device adapter:
# esxcli corestorage claiming unclaim -t location -A vmhba1
Rescan the adapter:
# esxcfg-rescan vmhba1