What is the meaning of this line:-
"Verify that the LUN is not set to read-only on the array." in this KB article
VMware KB: Troubleshooting LUN connectivity issues on ESXi/ESX hosts
anyone who can explain the meaning of this?
In some storage arrays you can put a LUN in read-only, this way hosts that have access to that LUN cannot write on them... for example, in some storage arrays you can create a copy of a LUN, and while the Target LUN is syncing with the Source LUN, the Target will be read-only.
Hello,
read-only LUNs are typically used for DR solutions like VMware SRM when you need cross site array replication. So you must present one member (LUN) of the pair to ESXi server as read-only.
As an example of array replication on Hitachi storage arrays is Hitachi True Copy technology with P-VOL (R/W) and S-VOL (R) volumes.
For more info see:
http://www.hds.com/assets/pdf/deploying-vmware-site-recovery-manager-5.0-on-hitachi-vsp.pdf
Regards,
P.