[c-nsp] Cisco 7301 IOS choice...

[Robert E. Seastrom]

"Steve Wright" <steve.wright at visp.me.uk> writes:

> Hi all,
>
> Currently looking at various IOS's and want to get some feedback as to what
> people are using and have found to be stable.
>
> This is for 7301's, that has either a PA-A[3/6]-OC3SMI in them, dealing with
> terminating L2TP DSL sessions. The sessions are handed off to us over 2 ATM
> PVC's, and the sessions balanced across the 2 with ~4k sessions at the
> present time.

My guess is that with just a couple of PVCs, you're fine with the
PA-A3.  Probably wouldn't get away with a PA-A1, but if it's 2 or 4
tunnel switches at the far end of each ATM PVC rather than talking
directly to a huge number of LACs (read: few enough L2TP tunnels to
count on the fingers of one hand), you might...  it's all a matter of
having enough sar buffers to go around.  you can save enough by being
cheap that it's worth scoping this out - run "show vpdn tunnel" to
scope this out.

No warranty expressed or implied in terms of the PA-A1 actually
working in the 7301 or how long it will continue to be supported in
*any* platform; I'm sure Rodney and Oliver can chime in on this one.

> Any specific recommendations as to what we should run that people have found
> stable?

As it happens, we're terminating L2TP tunnels as well, but over ethernet.

We're running 12.3(8)T7.  Had a little hinkiness with a runaway OSPF
Router process on a 7206VXR/npe300 running the same code, but overall
life has beeen pretty good.

Here's a 3-day "show proc cpu history" graph for a 7301 that's
handling about 1250 active sessions.  4 L2TP tunnels, 15900pps (in +
out), 27 Mbit/sec in, 44.5 Mbit/sec out, all peak, on the L2TP side.

    1111111121221221422111111111111112221221221212111111122122211221112121
    5566687809209009611698665345587881009009229080967657671922198109980829
100                                                                         
 90                                                                         
 80                                                                         
 70                                                                         
 60                                                                         
 50                 *                                                       
 40                 *                                                       
 30                 *                                    *                  
 20 *********###*************  *******#*****#***************###***#*****#***
 10 ########################################################################
   0....5....1....1....2....2....3....3....4....4....5....5....6....6....7.
             0    5    0    5    0    5    0    5    0    5    0    5    0 
                   CPU% per hour (last 72 hours)
                  * = maximum CPU%   # = average CPU%


Best,

                                        ---Rob