[pca] zpool unavailable after Kernel Patch 142909-17

[Paul B. Henson]

On 10/20/2010 7:29 AM, Glen Gunselman wrote:

> Thanks for the info. I am supporting a X4500 with 1TB disks. It has a on
> going problem where it hangs (can not invoke kernel debugger but no
> kernel dump/panic) and support has suggested I try S10U9 (currently
> running S10U7).

Interesting; I have 5 x4500's of similar configuration. Over the past 
six months I have had three occurrences of inexplicable hangs. Nothing 
is logged on either the system or the console. Based on circumstantial 
evidence I believe access to zfs is wedging. Initially the ssh port 
connects, but never displays a banner (telnet to port 22 I mean), and if 
left alone, it eventually refuses connections entirely. Given the 
complete lack of diagnostic evidence I hadn't bothered opening a support 
ticket, and was also planning to just try U9 to see if it perhaps goes 
away, as there are supposedly many zfs fixes in U9.

Sun's x86 machines are definitely a step down from the capabilities of 
their SPARC systems, even ones years older. If a problem like this 
occurred on one of my SPARC servers, I'd simply break into the prom and 
force a kernel panic, resulting in a nice juicy crash dump suitable for 
forensic analysis. As far as I can tell, the only way on x86 to make 
this happen is to initially boot the system from the kernel debugger, 
and leave it running under the debugger indefinitely until the problem 
occurs 8-/. I'm also still disgusted about the continued lack of serial 
console logging support on the ILOM :(.

I did finally get U9 running on my test x4500 (after battling some 
scalability issues with live upgrade, sordid details available at 
http://opensolaris.org/jive/thread.jspa?messageID=503177&tstart=0 if 
anyone's interested), and so far it seems to be working fine. All of the 
disks were recognized, and there were no problems importing or accessing 
any of the pools. I don't think this particular bug is a reason to delay 
an upgrade on this specific hardware...


-- 
Paul B. Henson  |  (909) 979-6361  |  http://www.csupomona.edu/~henson/
Operating Systems and Network Analyst  |  henson at csupomona.edu
California State Polytechnic University  |  Pomona CA 91768