Qos Issue in Cisco 3550

[thiru.vel10]

HI All,

I am facing Voice Quality issue in Cisco Ip phone.  However I don’t have any issue while calling between extension in the same Site.  I am facing voice quality issue while traffic flowing through the MPLS over GRE tunnel. Its working fine If I am removing the mls Qos in Cisco 3550 Interface.

Core Switch 4006.

Access layer Switch 3550.

L3 between Core and Access layer Switch.

sh mls qos int fa0/12 statis  

FastEthernet0/12  

Ingress  

  dscp: incoming   no_change  classified policed    dropped (in bytes)  

    46: 35393978   3387798    33358      0          0  

    0 : 2355401    2340850    14282944   0          0  

Others: 1315189175 1173684911 159208693  0          0  

Egress  

  dscp: incoming   no_change  classified policed    dropped (in bytes)  

    46: 29636772      n/a       n/a      0          0  

    0 : 24254784      n/a       n/a      0          0  

Others: 3608870199    n/a       n/a      0          0  

I removed the Qos on 4500 switches and mapped the cos 5 to queue 4 on 3550 but this did not fix the issue.

It was working fine and suddenly the voice quality issue happen. 

[Kishore Chennupati]

hi,

can you post the config of the interface. Are you just enabling mls qos or are you actually trusting the markings from the phone as well. Is mls qos enabled globally on your switch?

HTH

Kishore

[thiru.vel10]

Hi Kishore

i enabled the mls Qos in Globally ,

mls qos map cos-dscp 0 8 16 26 32 46

mls qos min-reserve 5 170

mls qos min-reserve 6 10

mls qos min-reserve 7 65

mls qos min-reserve 8 26

mls qos

switchport access vlan 10

switchport mode access

switchport voice vlan 11

mls qos trust cos

wrr-queue bandwidth 20 1 80 1

wrr-queue min-reserve 1 5

wrr-queue min-reserve 2 6

wrr-queue min-reserve 3 7

wrr-queue min-reserve 4 8

wrr-queue cos-map 1 0 1 2

wrr-queue cos-map 3 3 4 6 7

wrr-queue cos-map 4 5

priority-queue out

spanning-tree portfast

If i am removing the mls qos in interface ., the Voice quality is Improved ...

Switch Model 3550

IOS : c3550-i5q3l2-mz.121-20.EA1

I have tried to Upgraded the IOS but no Luck ....