CS1K and phones drop one way 3 secs

[mucca]

Hello guys , anyone seen this problem ,one way communication for a few seconds then the other end is back to normal ?
It is intermittent and I do not think it is a QOS issue as they do not experience any wierd sound once conversation has commenced.they have 3 X 5500 switches accross 3 floors and the problem is not related to any particular floor or switch.

Any help much appreciated,
thanks in advance.

Mucca

 

[biv343]

Any MLT/SMLT involved in the environment? I've experienced that issue myself when using SMLT at the core without disabling spanning tree on the uplink ports. Thats my first guess without many details.

 

[mucca]

Big thanks biv343 , not sure if that is the issue but I will check it out tomorrow , any more info much appreciated ,

Mucca

 

[vanraider81]

Hello Mucca,

On top of Biv343's suggestion, another check you can make is to confirm both devices, switch and phone, are configured for auto negotiate. If one device is not, you will end up in a half duplex scenario (duplex mismatch). This can cause problems.

 

[VinceWhirlwind]

A duplex mismatch will not give you one-way voice.

I'd also check what version of code you have on your switches - as mentioned above, some very weird stuff goes on with SMLT sometimes.

 

[vanraider81]

I agree that it wouldn't be one way speech path on a sustained basis, it is only a suggestion with the limited details.

However, depending on traffic levels that are possibly going on, packets can be dropped based on the duplex, this can result in certain voice problems.

Agree that switch versions should be checked as well.