IP SLA on Catalyst switches

[jgeralsky]

Hello All,

I have some issue with IP SLA.

Here is the configuration of IP SLA :

ip sla responder

ip sla logging traps

ip sla 11

udp-jitter 10.177.0.50 5000

tos 160

tag jitter_10.177.0.50

ip sla 12

udp-jitter 10.177.0.54 5000

tos 160

tag pathEcho_10.177.0.58

history lives-kept 1

history buckets-kept 1

history filter all

and here is the result :

Time	Time Created	Message	Source	Count
13.4.2011 9:37	13.4.2011 9:05	RTR 12   (jitter_10.177.0.54): The average packet-loss is now 6.000 % (threshold:   0.100%).	10.9.208.4(1)	10

As you can see we have packet loss 6 % for packet marked with TOS 160.

I have checked our devices (catalyst 6500 & catalyst 4500) and I didn’t find any packet drops related to voice packets.

The queing mechanism is WRR 1p3q8t .

Any suggestions ?

[cadet alain]

Hi,

 have checked our devices (catalyst 6500 & catalyst 4500) and I didn’t find any packet drops related to voice packets.

Are  your voice packets marked with DSCP 40( ToS 160) ? Aren't they marked with DSCP 46 ( ToS 184) ?

Regards.

Alain.

[jgeralsky]

Hi Cadet,

Voice packets are marked with DSCP 46 but both DSCP 40 & 46 are in COS 5.

The output queing mechanism is WRR 1p3q8t .

Packets dropped on Transmit:
     BPDU packets:  0

    queue              dropped  [cos-map]
     ---------------------------------------------
     1                        0  [1 ]
     2                    28874  [0 2 ]
     3                        0  [3 4 ]
     4                        0  [5 6 7 ]

  Packets dropped on Receive:
     BPDU packets:  0

    queue              dropped  [cos-map]
     ---------------------------------------------
     1                        0  [0 1 2 3 4 5 6 7 ]

As I mentioned above, I don't see any packets dropped in queue 4 which is dedicated for COS5 as well.

The similar statistics I have for all devices.

Any idea ?

[cadet alain]

Hi,

Can you post diagram as well as post output of sh mls qos maps on both switches and show policy-map on both routers.

Regards.

Alain.