Cisco ASR1001 Exceeded 1 Million Routes

[alexloh83]

Hi Folks,

Below is my question and setup:

I have two Cisco ASR1001 routers, each of them connect to different ISP and receive full IPv4 routes via eBGP.

Between this two router, they are connect via iBGP.

We have about 640K routes learned from ISP on each router, and additional 500-640K routes learned from iBGP.

My question is, as per my understanding, Cisco ASR1001 (8GB RAM) can only support up to 1 million routes, but if I add up eBGP (640K) + iBGP (550K) it already exceeded the limit, but why my router still functioning as normal? Then what does 1 million limitation mean for? Is 1 million per peer? Or 1 million per chassis (Route Processor)?

[ajay chauhan]

Saying just ASR 1001 would be very generic , route capacity will depend on ESP card + RAM. 

http://www.cisco.com/c/en/us/products/collateral/routers/asr-1000-series-aggregation-services-routers/datasheet-c78-731640.html

In case of your scenario it will double of bgp table but routing table which is programmed in FIB would be limitation what datasheet says.

hope this help.

Ajay 

[Pawan Raut]

My logic is you have two ISPs and there are some common prefixes which are receiving from both ISP router keep the entry for any one path (which is best path) in MIB table that reduce your total prefixes count.

Regards,

Pawan