SWITCH_QOS_TB-5-TRUST_DEVICE_LOST affecting 7941 phones only

[Will Pettit]

Hi, 

We've got a weird problem that seems to only affect 7941 and 7970 phones. We've getting a lot of errors in the logs on the switches:

Feb 20 14:17:34: %SWITCH_QOS_TB-5-TRUST_DEVICE_LOST: cisco-phone no longer detec
ted on port Fa2/0/21, operational port trust state is now untrusted.
Feb 20 14:19:12: %SWITCH_QOS_TB-5-TRUST_DEVICE_LOST: cisco-phone no longer detec
ted on port Fa2/0/23, operational port trust state is now untrusted.
Feb 20 14:26:12: %SWITCH_QOS_TB-5-TRUST_DEVICE_LOST: cisco-phone no longer detec
ted on port Fa2/0/6, operational port trust state is now untrusted.
Feb 20 14:30:10: %SWITCH_QOS_TB-5-TRUST_DEVICE_DETECTED: cisco-phone detected on
 port Fa2/0/6, port's configured trust state is now operational.
Feb 20 14:35:32: %SWITCH_QOS_TB-5-TRUST_DEVICE_DETECTED: cisco-phone detected on
 port Fa2/0/21, port's configured trust state is now operational.
Feb 20 14:35:55: %SWITCH_QOS_TB-5-TRUST_DEVICE_DETECTED: cisco-phone detected on
 port Fa2/0/23, port's configured trust state is now operational.

When you look at the devices that are affected by this, it's only 7941 and 7970 phones. These phones are experiencing "robot" voices and the call quality is terrible.

This was only affecting one particular switch stack (3750's - 5 in a stack mixture of v1 and v2's, all on the latest firmware). This is now affecting another site on another 3750 switch stack (on older firmware). The phones are all on the latest firmware and we've tried rolling back the firmware, but it's still happening.

Struggling to get a support case logged as the individual phones and switches aren't on support, but the CUCM servers are.

Any ideas what might be causing this?

[Divina Vitorino]

Please share with us the configuration of any interface showed in the error and your QoS config.

[Will Pettit]

All the ports have our standard config on them:

interface FastEthernet1/0/6
 switchport access vlan 309
 switchport voice vlan 415
 no logging event link-status
 srr-queue bandwidth share 10 10 60 20
 srr-queue bandwidth shape 10 0 0 0
 priority-queue out
 mls qos trust device cisco-phone
 mls qos trust cos
 no snmp trap link-status
 auto qos voip cisco-phone
 storm-control broadcast level 5.00
 storm-control multicast level 5.00
 spanning-tree portfast
 service-policy input EndUser
end

global qos:

mls qos map policed-dscp  24 26 46 to 0
mls qos map cos-dscp 0 8 16 24 32 46 48 56
mls qos srr-queue input bandwidth 90 10
mls qos srr-queue input threshold 1 8 16
mls qos srr-queue input threshold 2 34 66
mls qos srr-queue input buffers 67 33
mls qos srr-queue input cos-map queue 1 threshold 2 1
mls qos srr-queue input cos-map queue 1 threshold 3 0
mls qos srr-queue input cos-map queue 2 threshold 1 2
mls qos srr-queue input cos-map queue 2 threshold 2 4 6 7
mls qos srr-queue input cos-map queue 2 threshold 3 3 5
mls qos srr-queue input dscp-map queue 1 threshold 2 9 10 11 12 13 14 15
mls qos srr-queue input dscp-map queue 1 threshold 3 0 1 2 3 4 5 6 7
mls qos srr-queue input dscp-map queue 1 threshold 3 32
mls qos srr-queue input dscp-map queue 2 threshold 1 16 17 18 19 20 21 22 23
mls qos srr-queue input dscp-map queue 2 threshold 2 33 34 35 36 37 38 39 48
mls qos srr-queue input dscp-map queue 2 threshold 2 49 50 51 52 53 54 55 56
mls qos srr-queue input dscp-map queue 2 threshold 2 57 58 59 60 61 62 63
mls qos srr-queue input dscp-map queue 2 threshold 3 24 25 26 27 28 29 30 31
mls qos srr-queue input dscp-map queue 2 threshold 3 40 41 42 43 44 45 46 47
mls qos srr-queue output cos-map queue 1 threshold 3 5
mls qos srr-queue output cos-map queue 2 threshold 3 3 6 7
mls qos srr-queue output cos-map queue 3 threshold 3 2 4
mls qos srr-queue output cos-map queue 4 threshold 2 1
mls qos srr-queue output cos-map queue 4 threshold 3 0
mls qos srr-queue output dscp-map queue 1 threshold 3 40 41 42 43 44 45 46 47
mls qos srr-queue output dscp-map queue 2 threshold 3 24 25 26 27 28 29 30 31
mls qos srr-queue output dscp-map queue 2 threshold 3 48 49 50 51 52 53 54 55
mls qos srr-queue output dscp-map queue 2 threshold 3 56 57 58 59 60 61 62 63
mls qos srr-queue output dscp-map queue 3 threshold 3 16 17 18 19 20 21 22 23
mls qos srr-queue output dscp-map queue 3 threshold 3 32 33 34 35 36 37 38 39
mls qos srr-queue output dscp-map queue 4 threshold 1 8
mls qos srr-queue output dscp-map queue 4 threshold 2 9 10 11 12 13 14 15
mls qos srr-queue output dscp-map queue 4 threshold 3 0 1 2 3 4 5 6 7
mls qos queue-set output 1 threshold 1 138 138 92 138
mls qos queue-set output 1 threshold 2 138 138 92 400
mls qos queue-set output 1 threshold 3 36 77 100 318
mls qos queue-set output 1 threshold 4 20 50 67 400
mls qos queue-set output 2 threshold 1 149 149 100 149
mls qos queue-set output 2 threshold 2 118 118 100 235
mls qos queue-set output 2 threshold 3 41 68 100 272
mls qos queue-set output 2 threshold 4 42 72 100 242
mls qos queue-set output 1 buffers 10 10 26 54
mls qos queue-set output 2 buffers 16 6 17 61
mls qos

Thanks

[Divina Vitorino]

It seems that you are experiencing a conflict between auto qos and and the qos policy that you are using. you are using both commands: 

auto qos voip cisco-phone

mls qos trust device cisco-phone

You have to choose if you'll use your qos settings for cisco-phone or auto qos. In fact, I'd use auto qos. Works just fine for IP Phones. 

[russell.sage]

I have this problem across 6941 and 7841 phones running SCCP and SIP. Like you I also have the same configuration of auto and manual qos. Did you change your qos policy and if so did it resolve your issue.

[Will Pettit]

I removed the "mls qos trust device cisco-phone" command from the ports and it worked for most but not all of them. In most cases we just swapped the 7941 for another model and then deployed that somewhere else. Doesn't happen on all switch stacks, even though we've got the same setups/configs on all our switch stacks.

[LeeAnnChilders]

I ran into this issue with a cat5 cable on a 1G phone. After swapping it out, issues were resolved.