DiffServ and QOS for VOIP

[kenmiecomputer]

I am trying to implement QOS for VOIP but can't seem to get any of the packets to go into the priority queue. This is an Avaya phone system that is tagging the packets with DSCP of 46 and 34 and COS of 5. I have 2950 switches and 1760 routers. Below are the configurations that I have in place. There is onle one VLAN (long story). What am I missing?

If I do a "show policy-map int s0/0" I see the below output but as you can see there are no matches:


Serial0/0

Service-policy output: voipQoS

Class-map: VoIP (match-any)
0 packets, 0 bytes
5 minute offered rate 0 bps, drop rate 0 bps
Match: ip dscp ef
0 packets, 0 bytes
5 minute rate 0 bps
Match: ip dscp af41
0 packets, 0 bytes
5 minute rate 0 bps
Queueing
Strict Priority
Output Queue: Conversation 264
Bandwidth 768 (kbps) Burst 19200 (Bytes)
(pkts matched/bytes matched) 0/0
(total drops/bytes drops) 0/0

Class-map: class-default (match-any)
6818395 packets, 1036550438 bytes
5 minute offered rate 0 bps, drop rate 0 bps
Match: any
Queueing
Flow Based Fair Queueing
Maximum Number of Hashed Queues 256
(total queued/total drops/no-buffer drops) 0/58/0
exponential weight: 9

dscp Transmitted Random drop Tail drop Minimum Maximum Mark
pkts/bytes pkts/bytes pkts/bytes thresh thresh prob
af11 0/0 0/0 0/0 32 40 1/10
af12 0/0 0/0 0/0 28 40 1/10
af13 0/0 0/0 0/0 24 40 1/10
af21 0/0 0/0 0/0 32 40 1/10
af22 0/0 0/0 0/0 28 40 1/10
af23 0/0 0/0 0/0 24 40 1/10
af31 0/0 0/0 0/0 32 40 1/10
af32 0/0 0/0 0/0 28 40 1/10
af33 0/0 0/0 0/0 24 40 1/10
af41 0/0 0/0 0/0 32 40 1/10
af42 0/0 0/0 0/0 28 40 1/10
af43 0/0 0/0 0/0 24 40 1/10
cs1 0/0 0/0 0/0 22 40 1/10
cs2 0/0 0/0 0/0 24 40 1/10
cs3 0/0 0/0 0/0 26 40 1/10
cs4 0/0 0/0 0/0 28 40 1/10
cs5 0/0 0/0 0/0 30 40 1/10
cs6 1593/122843 0/0 0/0 32 40 1/10
cs7 0/0 0/0 0/0 34 40 1/10
ef 0/0 0/0 0/0 36 40 1/10
rsvp 0/0 0/0 0/0 36 40 1/10
default 6816750/1036381477 21/17228 37/31356 20 40 1/10

___________________
Router Config:

!
class-map match-any VoIP
match ip dscp ef
match ip dscp af41
!
policy-map voipQoS
class VoIP
priority 768
class class-default
fair-queue
random-detect dscp-based
!
interface FastEthernet0/0
no ip address
speed auto
!
interface FastEthernet0/0.1
encapsulation dot1Q 1 native
ip address x.x.x.x x.x.x.x
!
interface Serial0/0
bandwidth 1544
no ip address
service-policy output voipQoS
encapsulation frame-relay
no ip mroute-cache
service-module t1 timeslots 1-24
frame-relay lmi-type ansi
!
interface Serial0/0.1 point-to-point
ip address x.x.x.x x.x.x.x
frame-relay interface-dlci 100 IETF
!

Switch Config:

interface FastEthernet0/1
switchport mode trunk
switchport priority extend trust
no ip address
duplex full
speed 100
spanning-tree portfast
!

 

[kenmiecomputer]

yeah, sorry about that.

See the link below that talks about a tool that can determine when a marking has been changed. Now, if I only had a copy...

http://www.geant.net/server/show/nav.00700a009005

Looks like I may have to get TAC involved. Once we get it working I'll let you know what it took to make it work...

 

[kenmiecomputer]

Some success, if I ping with a TOS of 184 from the switch to yahoo.com I now see the packets getting prioritized on the router (FINALLY!). However, if I ping from the server (on port GIG02) I don't see it, nor do I see it when the switch pings one of the remote sites, ie, the firewall is sending the packets to the remote site via a VPN tunnel and the router never sees them, that I can work around. For now I need to figure out why the switch can successfully send a ping that gets priority but a device connected to the switch can not...

 

[ADB100]

The DSCP values will be lost when transmitted through a tunnel. Cisco have copy the DSCP values from the encrypted packets to the tunnel packets when using GRE but it isn't a standard. I think you are a bit knackered here unless the SonicWALL does something similar.

Andy

 

[ETBOY]

Hi ADB100,

How can i configure QOS or what kind of QoS should i configure in routers when I have GRE tunnels.?

Best Regards
MC

 

[ADB100]

I can't remember where this functionality was added to IOS but with GRE tunnels the TOS field is copiued from the encapsulated packet to the GRE IP Packet. There is a document on CCO regarding it but I would have to check.

If you are looking at just prioritising all GRE packets I am not sure?

Andy