amd64/145768: can't perform I/O on SAS based SAN disk in freebsd 7 and 8

[Kevin]

>Number:         145768
>Category:       amd64
>Synopsis:       can't perform I/O on SAS based SAN disk in freebsd 7 and 8
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    freebsd-amd64
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat Apr 17 00:30:01 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Kevin
>Release:        7 and 8
>Organization:
ISTC
>Environment:
using  amd64 kernel. same issue is on freebsd 7.2, 8.0 and FreeBSD-8.0-STABLE-201004-amd64-dvd1.iso
>Description:
the system can perform I/O request on local disk(a sas disk direct attached on 1064E),  can do any i/o request on remoter disk(a LUN crated on RSSM of BCS also connected throw 1064E). System can see the disk(LUN),create partition and mount. even create folder on it. but when you copy many and large file to it, it report many io errors. if you stress the i/o, system will hang.

Here is the link about BCS http://www-03.ibm.com/systems/bladecenter/hardware/chassis/blades/index.html.

BCS has a Disk storage module and a RSSM in i/o bay 3and 4. It a SAN based on SAS connection.
>How-To-Repeat:
install freebsd and copy file to external disk
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: