[c-nsp] Cisco 6509-E & WiSM - OIR

[Steve Shaw]

Guys,
I second (or third) the "do it inside a maintenance window" recommendation.
The effect of doing an OIR in a 6500 chassis really depends on the types of
modules within the chassis at that time....basically--

DFCs = OK
CFC=bus stall i.e. traffic loss

I've personally been bitten by doing an OIR during the day in a 6500 with
CFC modules.

Here's some literature from Cisco:

http://www.cisco.com/en/US/products/hw/switches/ps708/products_qanda_item09186a00809a7673.shtml#qa4

The addition of a DFC module effectively disconnects a module from the Data
Bus. As such, a DFC-enabled module is not subject to the bus stall mechanism
that occurs when a module is inserted or removed from the chassis.
Throughout these Online Insertion and Removal (OIR) events, the Data Bus is
temporarily paused for just enough time to ensure that the insertion/removal
process does not cause any data corruption on the backplane. This protection
mechanism causes a very brief amount of packet loss (sub-second, but
dependent on the time it takes to fully insert a module). A module with a
DFC onboard is not directly affected by this stall mechanism and does not
have any packet loss on OIR.

-Steve

On Wed, Aug 12, 2009 at 12:31 PM, Gert Doering <gert at greenie.muc.de> wrote:

> Hi,
>
> On Wed, Aug 12, 2009 at 03:08:52PM +0100, Nick Hilliard wrote:
> > >My gut feeling is telling me it's okay; but I figure I'd ask the group J
> >
> > "Online insertion and removal" or "online insertion and reload"?
> >
> > Definitely the latter.  Unfortunately, OIR stability is a hardware
> problem
> > and cannot really be avoided on the c65k/c76k chassis, regardless of the
> > line card in question.
> >
> > There's a little more information on:
> >
> > http://en.wikipedia.org/wiki/Catalyst_6500#Online_Insertion_.26_Removal
> >
> > Personally, I've never had any problems,  [..]
>
> Personally, I think that this is all folklore from the 7500 times...
>
> We *never* had any problems with OIR on 7200 or 6500/7600 platforms - but
> lots of fun with CyBUS stalls and crashes on 7500...
>
> gert
>
> --
> USENET is *not* the non-clickable part of WWW!
>                                                           //
> www.muc.de/~gert/
> Gert Doering - Munich, Germany
> gert at greenie.muc.de
> fax: +49-89-35655025
> gert at net.informatik.tu-muenchen.de
>
> _______________________________________________
> cisco-nsp mailing list  cisco-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/cisco-nsp
> archive at http://puck.nether.net/pipermail/cisco-nsp/
>