EMC QLA22xx User Manual

Error Message ID: 51 in event viewer when attempting to install 
multiple host access (for clustering) to the same EMC CLARiiON 
array storage group. The text of the message is:

An Error was detected on device \Device\Harddisk

<x>\DR<x> 

during a paging operation

Until host cluster software is installed, only a single host should 
access a storage group at a time.  Refer to the EMC Support Matrix for 
supported host configurations.

EMC Primus case emc29097 — If using HBAs connected to both 
CLARiiON SPs, without PowerPath installed, duplicate LUNs will be 
visible in the Device Manager and Disk Manager. Only one instance 
of the LUN will be accessible, and all other matching mappings will 
be listed as Unknown, Unreadable and Unallocated.

This is normal behavior when multiple paths are available, 
PowerPath is not installed, and the initiator type is registered in 
PowerPath mode (array default depending on core code revision).

EMC Primus case emc69307 — When using QLogic HBAs in a 
Brocade fabric environment, after upgrading Brocade 3900-series 
switch firmware to 3.0.2m, the HBAs report repeated link errors, and 
intermittently lose fabric connectivity.  

PowerPath may report paths lost and then found in quick succession, 
and repeated Windows 2000 event log error entries for Link 
Down/Link Up events similar to the following: 

Event ID: 11
Source: ql2300
Description: The driver detected a controller error on \Device\Scsi\ql2300x.
Data (words): offset 34 = 80120000 [ErrorCode: Link down error]
 
Event ID: 11
Source: ql2300
Description: The driver detected a controller error on \Device\Scsi\ql2300x.
Data (words): offset 34 = 80110000 [ErrorCode: Link up]