Getting pretty close to default IPv4 route maximum for 6500/7600 routers.

Jon Lewis jlewis at
Tue May 6 16:14:40 UTC 2014

On Tue, 6 May 2014, Drew Weaver wrote:

> Hi all,
> I am wondering if maybe we should make some kind of concerted effort to remind folks about the IPv4 routing table inching closer and closer to the 512K route mark.
> We are at about 94/95% right now of 512K.
> For most of us, the 512K route mark is arbitrary but for a lot of folks who may still be running 6500/7600 or other routers which are by default configured to crash and burn after 512K routes; it may be a valuable public service.
> Even if you don't have this scenario in your network today; chances are you connect to someone who connects to someone who connects to someone (etc...) that does.
> In case anyone wants to check on a 6500, you can run:  show platform hardware capacity pfc and then look under L3 Forwarding Resources.
> Just something to think about before it becomes a story the community talks about for the next decade.

I've been configuring 6500/Sup7203bxl's with
mls cef maximum-routes ip 768

The only gotcha is, you have to reload for that to be effective.

Speaking of which, I've had WS-X6708-10GE cards "go bad on reload" in a 
couple of 6500s.

I see cisco finally released some more info on their "bad memory" 
announcement from several months back:

It seems our "gone bad" 6708s may be included in this issue.  If you don't 
have enough spare ports or spare cards, this puts you in a somewhat 
precarious situation.  You need to reload to affect the v4/v6 route 
storage change, but you might lose some blades in the process.

  Jon Lewis, MCP :)           |  I route
                              |  therefore you are
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