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New Member

call interuption


I have a problem when I try to add switch WS-C2960-24PC-L (for IP phones) in cluster group which is defined on HSRP group of two 3550 switches. Claster group now has 16 members.

New WS-C2960-24PC-L swich and core WS-C3550-12G swich are connected over optic cable with GLC-SX-MM conector on 2960 side and WS-G5484 conector on 3550 side.

Only on new switch (this problem was never noticed on old switches) ip phones sometimes worked with problems (local and calles over PSTN were interupted very offen after several seconds,1-2 minutes).

Conigurations od central and new switch are in attachment.

IOS of core switch is c3550-i9q3l2-mz.121-13.EA1a.

How can I detect problem?

Best regards,
Miroslav Petkovic

  • IP Telephony
New Member

Re: call interuption


In this system there are callmanager 3.3 in production, two 3550 central  switches in HSRP, 16 other switches which are connected with optical  links to 3550 central switches.

It was cluster of 15 switches  (cluster group) configured on WS-C3550-12G - central + 14 other  switches. There are two existing switches which are not members of the  cluster, but devices which are connected work correctly.

I had to  connect 3 new WS-C2960-24PC-L switches in system, and to move exsiting  pnones and computers in new part of the building.

Problem which I  describe was happened when I connected first switch in system, and this  problem was never happened in other parts of the system. I configured  this switch as a part of cluster group (like last member of cluster - I  saw that 16 is maximum number of switches in cluster). In some part of  the day everithing work correctly, but occasionally local and calles  over PSTN (only with phones on this switch) were interupted after  several seconds,1-2 minutes, PCs (only on this switch) lose file  transfer connection. In callmanager ip phones didn't lose registration.

Situation  was worse when I tried to configure new switches independent from  cluster group. Haw I can debug this problem?

Best regards,

Miroslav Petkovic

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