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New Member

pvst problems and routing issues

I am having what seems to be routing issues between vlans on the central office to the branch office. No network changes were made to cause this. And everything the ISP has checked is OK. It looks normal everywhere also so I have done a packet capture on the WAN interface and i see a lot of PSVT+ activity each second. Could problems with PVST+ resemble inter vlan routing issues?

Cisco Employee

Re: pvst problems and routing issues

Please explain the exact problem being faced.

-amit singh

New Member

Re: pvst problems and routing issues

Basic config

The service provider is giving us layer 2 connectivity between all our sites. The central office is a cisco 3750 running as VTP server for vlan creation. SVI?s are created on the 3750 for vlan routing between the sites for phones and data. Vlan 122 ip address for Austin Data. Vlan 222 ip add for Austin phones. Vlan 15 ip address for broadcast equip. Vlan 14 ip for printers. On the Austin router the following interfaces are inter vlan 122 ip add and inter vlan 222 ip There are static routes that point back to the 3750 that show that they are directly connected.


All pc clients gateway receive the and the phones get The pc clients are intermittently (every 5 min) are losing connectivity to everything that is beyond gateway. The phones have not been identified with lost connectivity to CM at central office or locally. Austin pc clients can not see devices on other vlans locally. Central users can not connect to Austin pc clients unless they are on same vlan.

The type of config is currently working at 4 other branch offices.