PPPoE Subscriber limit on Bundle-Ethernet

[Asad Ul Islam]

Hello,

I need clarification on configuring PPPoE subscriber session on a Bundle-Ethernet interfaces on ASR 9010.

My requirement is achieving 128k Subscribers. 

I have 2 x MOD80Se  each having couple of  2x10g MPAs. 

I understand that each MOD80 has 2 NPU supporting 32k Subscribers each..  So if i don't bundle than each MPA can support 32k subscribers and i can easily reach 128k subscribers with 2 MOD80s.

But I want to configure subscribers on Bundle-Ethernet.  I would like to know if i bundle one 10G link from Each of the Four MPAs .. Will the bundle terminate 128k Subscriber???? 

Diagram attached for reference. 

[xthuijs]

great question!

So here is the deal, when you configure the bundle, all features are replicated to all npu's that have members in this bundle.

In your design, when you bundle 2 members with one member on a different NPU (or linecard for that matter) will cause you a "scale drop".this because a subscriber will created on both npu's that hold that member of that bundle.

To reach 128k subs you need to load all NPU's to their 32k max and if you want to use multimember bundles, then you will want to bundle them on the same NPU. But that somewhat may defeat your redundancy target of that bundle when you want to spread it over multiple bays or LCs.

regards!

xander

[Asad Ul Islam]

So if i put it in simple words... You are saying that Since logic is replicated to all NPUs in case of a bundle... The effective maximum subscribers on ONE BUNDLE interface will be just 32k  no matter how many npus are member of that bundle??

and to achieve 128k subscribers i will need to create atleast 4 Bundles with different npu for each bundle... Right??

[xthuijs · Accepted solution]

you got it!

And also, this 32k is not confined to the fact that you have bundle. It is the max a typhoon/NP4 NPU can provide. So even if you have a gig0/0/0/0 or whatever, that interface can also only do 32k.

BUT, if you have a bundle with 2 members on 2 different NPU's, then you are somewhat "reserving" these 32k subs on both NPU's and that reduces your scale a bit because then you can't use the NPU's individually.

So to reach 128k subs, you need at least 4 interfaces over 4 different NPU's, and noting that an LC has a limit of 64k also. (but sicne you have a mod80 with 2 NPU's only, that last point I made doesnt come into play, it would on a 24x10, 36x10, mod160 obviously which has more NPU's.

regards

xander

[Asad Ul Islam]

Thanks alot.

 I understood now how it works :)

Regards,

Asad