Microsoft Exchange 2003 SP2 failover issue

Hi,

We have encountered an issue whereby we are unable to failover any of our Exchange Virtual servers to any of the physical backend nodes.

Current Exchange setup (Active / Passive Environment)

3 Active backend servers:-
Exchange Backend server 1
Exchange Backend server 2
Exchange Backend server 3

1 Passive backend server:-
Exchange Backend server 4

We have 3 Exchange virtual servers whereby each Virtual server reside on 1 physical backend server:

Exchange Virtual server 1 resides on Exchange backend server 1
Exchange Virtual server 2 resides on Exchange backend server 2
Exchange Virtual server 3 resides on Exchange backend server 3

Last year Exchange backend server 2 had the following dirvers and firmware upgraded to improve TSM  backup performance:-

Exchange Backend server 2
Machine type: 8686
HBA Driver version 9.1.7.18
SSD Version: 1.6.3.0
Fibre Card adapters <QLA2340> whereby there are three cards assigned per server :-
BIOS version: 1.54
Driver version: STORport 9.1.7.18
Firmware Version: 3.03.25

The current driver / firmware versions that are running on the other servers are:-

Machine type: 8686
HBA Driver version 9.0.1.15
SSD Version: 1.5.1.2
Qlogic Fibre Card adapters <QLA2340> whereby there are three cards assigned per server :-
BIOS version: 1.43
Driver version: STORport 9.0.1.15
Firmware Version: 3.03.01

Despite the fact that Exchange backend server 2 was upgraded last year and we have numerous times been able to failover the Exchange Virtual servers onto this server successfully up till now, whereby out of four of the physical cluster disk only 3 come on line but the fourth one trys to attempt to come online but fails and thus fails the rest of that Virtual server resources back to another node.

This is the same issue happening on all the Exchange servers whereby only 3 physical disk cluster resources come online successfully, but the fourth ones doesn't on any node that you try to fail onto.

Seems like there is no clustering but the cluster log does not display any indications.

Also when I run SAN Surfer in the Link Status tab, it is displaying loss sync issue just on Exchange backend server 2, the rest of the Exchange backend servers are fine.

Any ideas?

Regards

Aamir