[c-nsp] cisco memory bug / propabilities?

[Jon Lewis]

On Fri, 31 Oct 2014, Gert Doering wrote:

> there's the infamous cisco memory bug "reboot and see your boxes die" - with
> the recent IOS software fixes, I have a couple of 6500s that need a reboot
> now, and I'm a bit scared - read: do I plan for "I reboot as usual, and
> there is a remote chance that hardware will not come back, so ensure
> a longer-than-planned outage is acceptable", or "I really should have a
> full set of spare boards sitting beside the to-be-rebooted box, because
> 90% of all boards will die"...?

If at all possible, I wouldn't do the reboots unless you have spares 
on-hand for the at-risk cards.

> What are *your* experiences with dieing cisco memory, in particular on 6500s?

I've rebooted 3 6500s with at-risk cards in the past year or so.  The 
first two were done before I was aware (I think before cisco announced) 
this issue.  Each of those first two lost a 6708.  For the last one, I was 
aware of the issue and had spares shipped to the site in advance.  Of 
course, that one didn't have any cards fail.

AFAIK, the problem is with the removable 1gb DIMMs on the cards...so you 
don't have to get spare Sups and line cards...you could just buy a couple 
of spare 1gb memory modules for them (if you have hands on-site you trust 
to do surgery on a card).  Unfortunately, on a card like the 6708, getting 
to that memory module is a PITA as it's under the DFC.


----------------------------------------------------------------------
  Jon Lewis, MCP :)           |  I route
                              |  therefore you are
_________ http://www.lewis.org/~jlewis/pgp for PGP public key_________