Maximum number of subscriber sessions supported on A9K-RSP880-LT-SE

[malik.naeem]

We have an ASR9006 with dual A9K-RSP880-LT-SE and 02x A9K-24X10GE-1G-SE line cards.

The A9K is running as a BNG in the network and the PPPoE sessions are terminating on a bundle-ether interface which means that sessions are handled by the RSP and not the LC.

The current number of PPPoE sessions is less that 30K but we want to enhance it to around 65k.

We know that we will have to increase the number of licenses (A9K-BNG-LIC-8K), but apart from the license restriction:

- what is the maximum number of concurrent PPPoE sessions that the A9K-RSP880-LT-SE can support?

- Also does it have any maximum throughput limit (when operating as a BNG)?

[smilstea]

It is a little challenging to answer that question without knowing 32bit vs 64bit, what software release version, ipv4/ipv6/dual stack, etc. These are older numbers that I have but the scale only goes up with newer releases, please note this is specific to RP based sessions, the scale is higher with LC based sessions. Also please note the legend at the bottom:

Session Type	5.3.4	6.1.4+	6.2.3+!	6.3.2!#+	6.5.1!#+/7.0.1!#+	7.1.1!^#
IPv4 Only sessions (PPPoE + IPoE)	128k	128k	128k	192k	256k	256k
IPv6 Only sessions (PPPoE + IPoE)	64k	80k	128k	128k	192k	256k
Dual Stack sessions (PPPoE + IPoE)	64k	80k	96k	128k	128k	256k
Sessions/LC  (Min 2 x NPU)	64k	64k	64k	128k	128k	128k
Sessions/NPU/Port / 1 NPU Linecard	32k	32k	64k/NPU 32k/Port	64k/NPU 32k/Port	64k/NPU 32k/Port	64k/NPU 32k/Port

+With RSP880/880-LT only

#With 64-Bit XR only

!With Tomahawk Line Cards Only

*With IPoE Only

^With RSP5-SE only

To answer another way with just 6.1.4 or above you can run dual-stack with 80k sessions.

Sam

[malik.naeem]

Hi Sam,

Thanks for the detailed response.

- We are running ver 7.0.2 (64 bit)

- IPv4 only (PPPoE & IPoE)

The sessions are handled by the RP so I believe that we should be able to scale upto 256k, correct?

Also, can you please share some reference document/link?

Regards,

Naeem

[smilstea · Accepted solution]

Right you have upto 256k with just ipv4, do be mindful of the per NP / per physical port limits.

Unfortunately scale numbers are kept internal.

Sam

[malik.naeem]

Thank you Sam.