[c-nsp] MLPPP

[Jason Berenson]

Rodney,

With the PA-MC-T3-EC, any idea how much would be offloaded to the PA?  
The router is running at about 75% peak average utilization, which is a 
bit high considering it's mostly doing routing and not pushing more then 
100Mbits.  If this is being interrupt switched, I wouldn't expect the EC 
PA to help, right?

-Jason

Rodney Dunn wrote:
> On Thu, Mar 26, 2009 at 10:30:08AM -0400, Jason Berenson wrote:
>   
>> Rodney,
>>
>> It's running: 12.4(18a).  I had to downgrade from the latest about 6 
>> months ago because of a bug where 'show policy' would show no output 
>> even if QoS was working properly.
>>
>> router#show int mul2 stat
>> Multilink2
>>          Switching path    Pkts In   Chars In   Pkts Out  Chars Out
>>               Processor          0          0          0          0
>>             Route cache      18049    3982931      25553   14234069
>>                   Total      18049    3982931      25553   14234069
>> router#show int mul2 stat
>> Multilink2
>>          Switching path    Pkts In   Chars In   Pkts Out  Chars Out
>>               Processor          0          0          0          0
>>             Route cache      18601    4110973      26553   14682852
>>                   Total      18601    4110973      26553   14682852
>>
>> fonseca#show cef in mul 2
>> Multilink2 is up (if_number 132)
>>  Corresponding hwidb fast_if_number 132
>>  Corresponding hwidb firstsw->if_number 132
>>  Internet address is 10.3.4.229/30
>>  ICMP redirects are always sent
>>  Per packet load-sharing is disabled
>>  IP unicast RPF check is disabled
>>  Inbound access list is not set
>>  Outbound access list is not set
>>  Interface is marked as point to point interface
>>  Hardware idb is Multilink2
>>  Fast switching type 7, interface type 105
>>  IP CEF switching enabled
>>  IP CEF VPN Feature Fast switching turbo vector
>>  IP Null turbo vector
>>  VPN Forwarding table "nypirg"
>>  Input fast flags 0x1000, Input fast flags2 0x0, Output fast flags 
>> 0x4000, Output fast flags2 0x0
>>  ifindex 127(127)
>>  Slot -1 Slot unit 2 Unit 2 VC -1
>>  Transmit limit accumulator 0x0 (0x0)
>>  IP MTU 1500
>>
>> Does that mean that there's no processor switching going on there? 
>>     
>
> Yep. It's all being interrupt switched so you should be fine.
>
>   
>> Why 
>> would a VRF make any difference to the MLPPP?
>>     
>
> forwarding vectors are different. But in this code we have the hooks
> to do MPLSoMLPPP if that's what you were doing..which you are not.
> The vrf interface on a bundle isn't what we call MPLSoMLPPP...that's when
> you enable MPLS on the bundle.
>
>   I see the same outputs 
>   
>> for a non VRF'd MLPPP.
>>     
>
> It's working as it should.
>
> With the new PA the overall CPU would be less b/c the mlppp work is offloaded
> to an asic on the PA.
>
>   
>> -Jason
>>
>> Rodney Dunn wrote:
>>     
>>> You have it in a VRF which really shouldn't cause an issue as it's
>>> tag2ip and ip2tag.
>>>
>>> What code is it?
>>>
>>> Make sure it's the latest 12.4 mainline as we did some work in 12.4 to make
>>> this work.
>>>
>>> Can you get a 'sh int mul 2 stat' after a clear counters...get it a few
>>> times and send it?
>>>
>>> Also, what are the other interface configs feeding this bundle?
>>> It could be features on them causing the punts.
>>>
>>> What does 'sh cef int' say?
>>>
>>>
>>> Rodney
>>>
>>> On Wed, Mar 25, 2009 at 05:03:03PM -0400, Jason Berenson wrote:
>>>  
>>>       
>>>> Here's a sample:
>>>>
>>>> interface Multilink2
>>>> ip vrf forwarding VPN1
>>>> ip address x.x.x.x 255.255.255.252
>>>> no cdp enable
>>>> ppp multilink
>>>> ppp multilink group 2
>>>> service-policy output voice
>>>> !
>>>> interface Serial6/0/25:0
>>>> no ip address
>>>> encapsulation ppp
>>>> down-when-looped
>>>> no cdp enable
>>>> ppp multilink
>>>> ppp multilink group 2
>>>> !
>>>> interface Serial6/0/26:0
>>>> no ip address
>>>> encapsulation ppp
>>>> down-when-looped
>>>> no cdp enable
>>>> ppp multilink
>>>> ppp multilink group 2
>>>> !
>>>>
>>>> -Jason
>>>>
>>>>
>>>> Rodney Dunn wrote:
>>>>    
>>>>         
>>>>> The G1's with MLPPP should not be process switching the traffic.
>>>>>
>>>>> What is the config?
>>>>>
>>>>> The EC cards just offload the MLPPP to the new asic on the PA.
>>>>>
>>>>> Rodney
>>>>>
>>>>> On Wed, Mar 25, 2009 at 04:35:50PM -0400, Jason Berenson wrote:
>>>>>
>>>>>      
>>>>>           
>>>>>> Greetings,
>>>>>>
>>>>>> I've got a 7206VXR NPE-G1 with a bunch of DS3 cards in it (PA-MC-T3).  
>>>>>> There's about 25 multilinks with an average of 2 T1s per bundle.  I see 
>>>>>> a lot of process switching on the router and I have a feeling it's 
>>>>>> because we don't have the PA-MC-T3-EC card so the processor has to step 
>>>>>> in for the MLPPP. 
>>>>>>
>>>>>> Is this the case?  If I get some PA-MC-T3-EC cards to swap in, will 
>>>>>> that take a lot of load off the NPE-G1?  Any output needed, please let 
>>>>>> me know.
>>>>>>
>>>>>> Thanks,
>>>>>> Jason
>>>>>> _______________________________________________
>>>>>> cisco-nsp mailing list  cisco-nsp at puck.nether.net
>>>>>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>>>>>> archive at http://puck.nether.net/pipermail/cisco-nsp/
>>>>>>   
>>>>>>        
>>>>>>