Like we have for the last two?
I¹m really surprised that most people have not hit this limit already,
especially on the 9K¹s, as it seems Cisco has some fuzzy math when it
comes to the 512K limit.
Also make sure you have spare cards when you reload after changing the
scaling, those old cards don¹t always like to come back.
Do the ASR1k routers have this issue as well? I searched around but
couldn't find any information.
Do the ASR1k routers have this issue as well? I searched around but couldn't find any information.
Not really (according to Cisco) -
ESP10 - 1,000,000 IPv4 or 500,000 IPv6 routes
ESP20 - 4,000,000 IPv4 or 4,000,000 IPv6 routes
ESP40 - 4,000,000 IPv4 or 4,000,000 IPv6 routes
ESP100-4,000,000 IPv4 or 4,000,000 IPv6 routes (hardware is capable of 8,000,000 routes)
ESP200-4,000,000 IPv4 or 4,000,000 IPv6 routes
ASR1k doesn't have fixed TCAM like the 6500 and has a little more wiggle
room, but it depends on the ESP you have installed. For example ESP 20
supports around 1,000,000 routes.
-Pete
Asr1002-f may have problem as it limited to 512k iirc
It depends, you can put in a table-map to stop the routes from being
installed into the FIB/RIB on an ASR-1K with 2GB of RAM you can then have
up to 2 million IPv4 routes. Alternatively, if you are not using your
ASR-1k to forward traffic, I think you could also just turn off CEF and
have the same result.
Helpful only if you don't want to forward traffic through
the box, in which case running IOS XE on a VM on a server is
a more lasting idea :-).
Mark.
I could never get an definitive answer out of TAC or my account team, but I
believe the ASR1002 w/ESP5 is also affected.
I know most people have problems with 2 bgp feeds and 4GB RAM on
ASR1002-F (as it max installable memory). So I doubt about 2M routes
with 2GB RAM.
I've never ran the ASR1002-F, but I know some other ASR1000
platforms consume half the memory just for the IOS image
upon boot.
This makes running a second instance of IOSd on boxes that
have a single RP a sure way to lead to a crash when the same
box is running BGP (happened to me once, 2nd IOSd never
again).
Mark.
From: NANOG [mailto:nanog-bounces@nanog.org] On Behalf Of Irwin, Kevin
Sent: Wednesday, May 07, 2014 4:39 PM
I¹m really surprised that most people have not hit this limit already, especially
on the 9K¹s, as it seems Cisco has some fuzzy math when it comes to the
512K limit.
I would actually be very surprised if someone would hit the 512K limit on ASRs.
With 6500/7600 I can understand they've been around for ages and no one anticipated the 512k limit back then.
But ASRs? When these where bough engineers must have known that 512k is not going to be enough.
I guess one does some reading and tweaking before installing a box as a PE or Internet Edge.
adam
Actually, it *was* anticipated. It's just that those who designed the ASIC didn't necessarily envision that it would still be in service, having gone through successive additional minor variations, for quite so long.
The datasheet for the ESP-5 states support for 500,000 IPv4 Prefixes. The
TCAM on the ASR1k is different from 6500 and can't be adjusted in the same
fashion. You'd have to filter or upgrade the ESP.
http://www.cisco.com/c/en/us/products/collateral/routers/asr-1000-series-aggregation-services-routers/data_sheet_c78-450070.html(ctrl+f
"Table 3")
My 2c:
The obvious thing for me is if people are running a full ipv4 route table on a box only just capable of handling one single table of that size, then really now is the time to asses if you really need to hold that table or just drop to default +internal+peers. If you have multiple up streams and you are using the route tables to do your route selection then great, but that means you need at least 1M capability now, and really 2+ should be your target. In my experience people running a full table on a small capability box normally don't actually need to carry it, or they just need a bigger box.
FIB is not the same as RIB...
Perfectly happy 6509, many paths, only one full table in the FIB:
BGP router identifier XXX , local AS number 11404
BGP table version is 40916063, main routing table version 40916063
494649 network entries using 71229456 bytes of memory
886903 path entries using 70952240 bytes of memory
29 multipath network entries and 58 multipath paths