Sorry for spelling TAC as TACS , but I've been installing alot of TACACS+ to
routers lately and I've got that on the brain.
""James Haynes"" <[EMAIL PROTECTED]> wrote in message
944u35$82v$[EMAIL PROTECTED]">news:944u35$82v$[EMAIL PROTECTED]...
> Hi all,
>
> We recently (yesterday) had a Cisco 7507 start acting funny in the middle
of
> the night (when else) and a few hours later rebooted itself. As this
router
> has never given us any problems before we were a bit concerned. Looking at
> the log files and some show commands located what appeared to be a
processor
> parity memory error. Not knowing what to make of this I opened a case with
> TACS and eventually received the reply shown below after sending the show
> tech-support file and log file to them.
>
> My question is:
>
> If the event represents a faulty memory module is there any way to monitor
> for such a problem beginning to occur again? Something perhaps in
CiscoWorks
> or some process that can be monitored. As this problem appeared to occur
> over an entire night I was thinking you may be able to see it coming. If
it
> truly was a random event then we shouldn't have to worry about it. Thx for
> any suggestions.
>
>
****************************************************************************
> ***************
> Reply from TACS:
>
> "The router crashed due to a processore parity memory
> error (PMPE). In a router that uses parity checking, each byte of data
> stored in memory has an associated parity bit.
> If the sum of the bits violates the even (or odd) arity rule, the basic
> input-output system halts the router with a message
> like "processor memory parity error". While having the router halted is
> certainly undesirable and is at the very least
> inconvenient, it is good news relative to some of the imaginable
> alternatives if the error were to have
> gone undetected.
>
> This could be due to several things:
>
> * Faulty Memory
> * Transient Memory Error.
>
> Faulty memory would cause more than one crash, so if the router has
crashed
> several times for this error
> it is most likely the cause of your problem. Howeve, if the parity crash
> happens no more than 1 time per month
> than the problem is most likely caused by an electrical transient error
> (Alpha particles) which are
> naturally occuring high energy particles that can strike parts of the
> silicon in DRAM transferring energy to them.
> This can cause a bit to change - hence a parity error. This is is not a
> hardware failure.
>
> Due to the fact that this is very hard to define, my recommendation is to
> monitor the router for further
> issues. If the crash occurs again or has happened several times in the
past,
> then the memory in the router
> needs to be replaced (on RSP)."
>
> Transient Parity Errors Described - PMPE from Cosmic Rays - IBM
> http://www.research.ibm.com/journal/rd/ziegl/zieglert.html
>
>
****************************************************************************
> ******************
>
>
>
>
> _________________________________
> FAQ, list archives, and subscription info:
http://www.groupstudy.com/list/cisco.html
> Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
>
_________________________________
FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html
Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
