[c-nsp] An observation: 512k default max-prefix in IOS-XR

Sat Apr 28 15:46:38 EDT 2012

8 years ago when Cisco introduced the 3BXL, 1M routes was a lot of routes,
more than 5 times the size of the current Internet routing table, now,
it's not.

1M routes also doesn't mean 1M routes. IPv6, Multicast and IPv6 Multicast
take up more space, further reducing the available tcam resources.

With an expanding IPv6 table and a never-ending fragmentation of the IPv4
space, plus whatever multicast and MPLS you are doing, it might prove to
be insufficient moving forward, and in some cases depending on what you're
doing, it might already be.

The L3XL kills off video monitoring and requires an even more expensive
license and this is one of the main reasons the ASR9k doesn't sound that
exciting to me at this point.  I'd like to see a lot more available tcam
space before committing to a new platform long term.

Kind regards,
Sibbi

On 28.4.2012 13:15, "Robert Blayzor" <rblayzor.bulk at inoc.net> wrote:

>On Apr 25, 2012, at 9:17 PM, Will Hargrave wrote:
>> So around 2015 or perhaps before, careless operators of both IOS-XR and
>>7600 boxes may have a shock. :-)
>
>
>Careless operators of 9K that don't change from the default scale maybe.
>That's just a default limitation on the 9K.
>
>Just change from the "default" scale to l3 or l3xl scale and you'll be
>good for 1M+ routes.  Of course L3 scale eats up L2 scale and vice versa,
>so choose your battles wisely.
>
>-- 
>Robert Blayzor
>INOC, LLC
>rblayzor at inoc.net
>http://www.inoc.net/~rblayzor/
>
>
>
>
>_______________________________________________
>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/