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Applying QOS on an 877W

I've been trying to configure LLQ on an 877w for a while now with little joy. I've tried matching classes on a range of criteria including dscp and access lists. In each case I then assign these classes to a policy map and then assign the policy map to my dialer interface (PPPoA).

I can see that the classes are matching my traffic, but when I look at the service policy statistics for the dialer interface, it shows no packets matched against the priority queue.

I've pasted below my class and policy maps:

class-map match-any VoIP-Signalling match access-group name VoIP-Signalling class-map match-any VoIP-Voice match access-group name VoIP-Voice ! policy-map QOS-Default class VoIP-Voice priority 64 class VoIP-Signalling bandwidth 20 class class-default fair-queue

The access lists used to match the classes above are below:

ip access-list extended VoIP-Signalling permit udp host 1.2.3.4 eq 5060 any ip access-list extended VoIP-Voice permit udp host 1.2.3.4 range 18000 18999 any permit udp host 1.2.3.4 eq 4569 any

I've checked that the ACLs are matching the voice traffic:

show access-lists VoIP-Voice Extended IP access list VoIP-Voice 10 permit udp host 1.2.3.4 range 18000 18999 any (1898 matches) 20 permit udp host 1.2.3.4 eq 4569 any show access-lists VoIP-Signalling Extended IP access list VoIP-Signalling 10 permit udp host 1.2.3.4 eq 5060 any (91 matches)

The Dialer interface has the following command added (trimmed for posting):

Interface Dialer10 service-policy output QOS-Default

When I run 'show policy-map interface dialer 10' I see the following:

Dialer10

Service-policy output: QOS-Default

Class-map: VoIP-Voice (match-any) 1898 packets, 125472 bytes 5 minute offered rate 0 bps, drop rate 0 bps Match: access-group name VoIP-Voice 1898 packets, 125472 bytes 5 minute rate 0 bps Queueing Strict Priority Output Queue: Conversation 72 Bandwidth 64 (kbps) Burst 1600 (Bytes) (pkts matched/bytes matched) 0/0 (total drops/bytes drops) 0/0

Class-map: VoIP-Signalling (match-any) 96 packets, 50166 bytes 5 minute offered rate 0 bps, drop rate 0 bps Match: access-group name VoIP-Signalling 96 packets, 50166 bytes 5 minute rate 0 bps Queueing Output Queue: Conversation 73 Bandwidth 20 (kbps)Max Threshold 64 (packets) (pkts matched/bytes matched) 0/0 (depth/total drops/no-buffer drops) 0/0/0

A couple of posts have raised similar questions - particularly whether it's even possible to apply a policy map to a dialer interface.

Any pointers would be gladly received!

Chris

Reply to
Can2002
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My understanding is that this only works with multilink ppp. I have not had the opportunity to try it out.

If you look at the documents very carefully the only examples given are mppp ones and often in the documents specific router models are mentioned which leads me to worry that support is platform dependent.

On the other hand this may work.

pvc 0/38 vbr-nrt 240 240 tx-ring-limit 2 encapsulation aal5mux ppp dialer dialer pool-member 1 service-policy output PM.to-internet

You NEED the vbr-nrt bit.

MAYBE you need also:-

interface Dialer0 service-policy output PM.to-internet

Oh yes I remember.

My idea was to mark the packets in the dialer then do crypto with QoS pre-classify then hopefully the marked packets would be queued somewhere, or something.

I can't figure it out.

One thing about this latter config (PVC) that I don't follow is that the ATM interface has no clue about IP and yet documents suggest that you apply an IP based service policy to it. I find that baffling. No - make that really, really really baffling.

It may work though.

Let us know. I have done some testing and it does seem to be working but I did not do enough to be sure.

Reply to
Bod43

On the other hand,

Get a 2801 and put it inside your 877, not using the wireless.

Then you can do fine and beautiful traffic shaping and LLQ on the

2801's ethernet interfaces. That works very nicely for sure.

PS - LLQ does not work on BVIs. In this case it does tell you when you type it in which is nice.

Reply to
Bod43

Cheers for the responses,

I got to the bottom of it in the end; the policy map needs to be applied to the ATM sub-interface, not the dialer!

It took a fair amount of digging, but anfter tweaking the settings it kicked into gear!

Chris

Reply to
Can2002

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