urgent help needed: primary storage became unplugged after xenserver roboot

[Yiping Zhang]

Hi,  All:

I need some urgent help in restoring my CS instance (version 4.3.1).

After patching xenserver 6.2,  I rebooted the pool master (I have two xen 
hypervisors).  After the pool master comes back, the SR for the primary storage 
 became “unplugged”, and shown as broken in XenCenter.  The volume is not 
mounted on pool master host any more.

How do I get it back without losing any data ?

Thanks for all helps.

Yiping