Router recommendations for runing two full Internet routing tables

[Sosso]

Hi,

We are consedering running Multhoming with two ISP and /24  independant IP range. I want to get some advice on router/RAM selection to support two full bgp internet routing tables for the three next years.

Actually, we have an ISR 4331 with 4GB of DRAM, we are thing to uprade it with 16GB but I don't think that this model can support this configuration.

In advance, thank you for your help.

[Georg Pauwen]

It depends on what else you have running on the router, but in general, 1GB of memory is more than enough to hold the full BGP routing table. So the ISR 4331 with the default 4GB should be sufficient.

[Sosso]

Thanks Gerog,

The router will be dedicated to the multihoming configuration

Unfortunately, the router crash when it receives the full Intenet routing table so it's not possible to test it with two :)

We have also activated the performance licence but no change. The next step is to test it with 16GB, I think that it will work with one full internet tabel but not with 2 (it's my feeling)

Regards,

[o.panchuk]

As modern full-view size is around 700k for IPv4 and 60k for IPv6 so following routers will work.

ASR1000 series with RP1 can handle it:

●  Scalability up to 1,000,000 IPv4 routes or 500,000 IPv6 routes

●  BGP RR Scalability up to 5,000,000 IPv4 routes or 3,000,000 IPv6 routes

or better with RP2 :

With 8-GB memory:

●  Up to 1,000,000 IPv4 routes or 1,000,000 IPv6 routes

●  BGP RR Scalability up to 8,000,000 IPv4 routes or 6,000,000 IPv6 routes

With 16-GB memory:

●  Up to 4,000,000 IPv4 routes or 4,000,000 IPv6 routes

●  BGP RR Scalability up to 24,000,000 IPv4 routes or 17,000,000 IPv6 routes

[Sosso]

Hi Panchun,

As mentioned, we need a router that supports 2 full internet routing tables. On Sept 2018, the size of full-view is 770K for IPv4 (we don't need IPv6)
We need a router for arround 1,5M prefixes. So, considering your reply, the min configuration is the ASR1004 with 16GB ?

Thanks

[Georg Pauwen]

Hello,

1,5M prefixes require roughly 1,5GB of memory. It depends what else you have running on the router, but even the 1001X with 8GB of DRAM would probably be sufficient. That said, why do you need two full routing tables, are you an ISP ?

[Sosso]

Hello,
Are sure about that ? I don’t see any information about your calculation.
The router will be dedicated to do the multihoming configuration (only Internet routing), We have some /24 IP independent public range & 2 FAI (on two different sites) for the redundancy.

From Cisco :
All ISR4k platforms support a full Internet routing table (500k prefixes) with 8GB DRAM.
The 8GB DRAM is the bare minimum for the full bgp ipv4 route table supports.

But only ISR4451 supports two full Internet routing tables (1M prefixes) with 16GB DRAM.

[o.panchuk]

AFAIK asr1000-rp2 8GB + ESP20 is capable of running at least 3 ipv4 full-views + 3 ipv6 with different peers.

[Sosso]

Hello,



On paper, We can also use Cisco ASR 1001-X with 16GB



● Up to 3,500,000 IPv4 or 3,000,000 IPv6 routes - 16 GB Memory