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

[Bryan Tong <contact () nullivex com>]

The IPv6 table will not be as big as the v4 table even after full
acceptance. Given that most providers will be advertising a single /32 and
then rest will be some /48 routes for multi-homed scenarios.

My router looks like this

FIB TCAM maximum routes :
=======================
Current :-
-------
 IPv4                - 600k
 MPLS                - 32k
 IPv6                - 160k
 IP multicast        - 32k

Probably a little heavy on MPLS considering we dont use it. With the
current level of exhaustion I dont think IPv4 will make it past 600k.

We are currently seeing 520,000 routes.

There are currently 107M IPs left globally.

If those all went to /21's that would require 26,255 prefixes.
If those all went to /22's that would require 52,510 prefixes.
If those all went to /24's that would require 105,021 prefixes.

So even the most conservative maximum should be no more than 626K





On Mon, Jun 9, 2014 at 1:09 PM, Jon Lewis <jlewis () lewis org> wrote:

> Why, in your example, do you bias the split so heavily toward IPv4 that
> the router won't be able to handle a current full v6 table?  I've been using
>
>
> mls cef maximum-routes ip 768
>
> which is probably still a little too liberal for IPv6
>
> FIB TCAM maximum routes :
> =======================
> Current :-
> -------
>  IPv4                - 768k
>  MPLS                - 16k (default)
>  IPv6 + IP Multicast - 120k (default)
>
> given that a full v6 table is around 17k routes today.
>
> A more important question though is how many 6500/7600 routers will fully
> survive the reload required to affect this change?  I've lost a blade
> (presumably to the bad memory issue) each time I've rebooted a 6500 to
> apply this.
>
>
> On Mon, 9 Jun 2014, Pete Lumbis wrote:
>
>  The doc on how to adjust the 6500/7600 TCAM space was just published.
> > http://www.cisco.com/c/en/us/support/docs/switches/
> > catalyst-6500-series-switches/117712-problemsolution-cat6500-00.html
> >
> >
> > On Tue, May 6, 2014 at 3:48 PM, Pete Lumbis <alumbis () gmail com> wrote:
> >
> >  There is currently a doc for the ASR9k. We're working on getting on for
> > > 6500 as well.
> > >
> > >
> > > http://www.cisco.com/c/en/us/support/docs/routers/asr-9000-
> > > series-aggregation-services-routers/116999-problem-line-card-00.html
> > >
> > >
> > >
> > >
> > > On Tue, May 6, 2014 at 1:34 PM, <bedard.phil () gmail com> wrote:
> > >
> > >  I would like to see Cisco send something out...
> > > > -----Original Message-----
> > > > From: "Drew Weaver" <drew.weaver () thenap com>
> > > > Sent: яя5/яя6/яя2014 11:42 AM
> > > > To: "'nanog () nanog org'" <nanog () nanog org>
> > > > Subject: Getting pretty close to default IPv4 route maximum for
> > > > 6500/7600routers.
> > > >
> > > > 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.
> > > >
> > > > -Drew
> ----------------------------------------------------------------------
>  Jon Lewis, MCP :)           |  I route
>                              |  therefore you are
> _________ http://www.lewis.org/~jlewis/pgp for PGP public key_________



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