[c-nsp] Suggestion needed for Sub-interface & PVC creation

[Malik Naeem]

Dear James

In reference to your mail on NSP list in September 2004:

https://puck.nether.net/pipermail/cisco-nsp/2004-September/012779.html

We are running almost the same kind of services using Cisco 7206 as our 
BRAS. I have configured approximately 1000 sub-interfaces for our PPPoE 
subscribers, using the following configuration:

interface sub-interface point-to-point
  pvc VPI/VCI
   encapsulation aal5snap
   protocol pppoe
  !
end

	
We also want to run RBE & PPPoE simultaneously, which can be done easily 
by creating a separate sub-interface for RBE. I am facing some problems 
while handling all this stuff which are listed below:

1. Is it possible to create a multipoint sub-interface having PVC for 
both PPPoE and RBE?

2. As mentioned above I have created a large number of sub-interfaces 
i.e. separate sub-interface for each subscriber, as a result of which 
the size of our configuration is very large. Defining a PVC range on a 
single sub-interface reduces the configuration size. In your opinion, 
which approach is better creating separate sub-interfaces or a single 
sub-interface with a large PVC range? (Assuming that the type of service 
we are providing to all subscribers is same). Also tell me which one of 
the above techniques results in more CPU utilization.

3. Another strange problem being faced is that the sub-interfaces get 
stuck and need to be refreshed (i.e. "shutdown" and then "no shutdown"). 
I added the following lines in the sub-interface configuration:
	oam retry 3 5 1
	create on-demand

After adding the above two lines I noticed that a particular customer 
(who was facing this problem very often) didnt faced it again. Adding 
these two lines on all sub-interfaces will obviously cause increase in 
CPU utilization. Does anybody have any idea about the increase in CPU 
utilization caused by such oam queries?

Waiting for your suggestions.

Regards

Naeem-ud-Din
Operations Engineer
Dancom OnLine Services
Islamabad, Pakistan