ASR-9001-S BGN scaling

[Alexey Lavrov]

Hello!

How many IPv4 BNG session supported on ASR9001-S?

[Aleksandar Vidakovic]

hi Alexey,

You can configure up to 4k BGP peers by default on any IOS XR platform. The limit is not really in the number of peers but in the size of BGP database and the prefix churn.

asr9001-S has the identical control plane as asr9001, with 8GB RAM on the RP.

There is a good document on route scale which you may find useful:

https://supportforums.cisco.com/document/105496/asr9000xr-understanding-route-scale

regards,

Aleksandar

[Aleksandar Vidakovic]

sorry, Alexey. I misread the "BGN" in the title. I thought you were referring to "BGP". I should have read with more attention. :)

Aleksandar

[Fredrik Lönnman · Accepted solution]

It will support up to 32,000 BNG subscribers on the one (1) NP. There are quite a few caveats to that number though regarding queue chunk allocation and Bundle-Ethers.

[Alexey Lavrov]

Thank you, Fredrik.

If I upgrade 9001-s to 9000 I can use 2 NP and in case it will support 64,000 BNG subscribers?

What are caveats you mentioned? 
 

[Fredrik Lönnman]

Unfortunately no, there is also a platform wide limit of 32K subscribers, but with 2 NPs you of course get twice the throughput.

There are a few caveats, for one the queueing resources on the NP is divided into 4 resource chunks which supports up to 8K L3 (sub/parent) queues each. To fully utilize this you need to divide the subscribers on different ports or different subint/vlan per port, chunks can be divided per int/subint.

Also when using Bundle-Ethers every queue resource are counted once per member port, so having a subscriber facing 2x10G Bundle-Ether will populate twice the queues and effectively cut your subscriber count in half.

[smailmilak]

Hi,

does anyone know if we can terminate subscribers sessions on the integrated 10G interfaces or do we have to install one A9K-MPA-2X10GE LC?

[Fredrik Lönnman]

The integrated ports are fine, they are connected to the same NP as the active MPA.

[smailmilak]

Thanks to both of you.

[steinarrimestad]

Hi.

should be no problem using the integrated 10Gs, just be aware of the NP distribution on these is shared with the MPA modules.

RP/0/RSP0/CPU0:asr9001-1#show plat
Wed Mar 23 10:05:57.384 CET
Node Type State Config State
-----------------------------------------------------------------------------
0/RSP0/CPU0 ASR9001-RP(Active) IOS XR RUN PWR,NSHUT,MON
0/0/CPU0 ASR9001-LC IOS XR RUN PWR,NSHUT,MON
0/0/0 A9K-MPA-20X1GE OK PWR,NSHUT,MON
0/0/1 A9K-MPA-4X10GE OK PWR,NSHUT,MON
RP/0/RSP0/CPU0:asr9001-1#show controllers np ports all
Wed Mar 23 10:06:03.862 CET

Node: 0/0/CPU0:
----------------------------------------------------------------

NP Bridge Fia Ports
-- ------ --- ---------------------------------------------------
0 0 0 GigabitEthernet0/0/0/0 - GigabitEthernet0/0/0/19
0 0 0 TenGigE0/0/2/0, TenGigE0/0/2/1
1 1 1 TenGigE0/0/1/0, TenGigE0/0/1/1, TenGigE0/0/1/2, TenGigE0/0/1/3
1 1 1 TenGigE0/0/2/2, TenGigE0/0/2/3