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Connecting 2950 to existing LAN

I recently purchased a WS-C2950T-24 to add to my existing network. I have mirrored the configuration of other 2950 switches in other offices (with exception of name and subnet info that differs between sites). The existing LAN in this office is comprised of 4 cisco WS-C2924-XL switches. I can connect to all 4 of the 2924 switches but not to the 2950. Any known issues of talking between the two different types of switches?


Re: Connecting 2950 to existing LAN

Its not a good practice to enable portfast on all the interfaces. It should be done only when the connection is terminated to an end host.

I think your problem is because of the trunk between the 2924XL and the 2950. The 2924 switch supports both dot1q and ISL trunk encapsulation whereas the 2950 supports only dot1q

try this

on the 2924XL port connecting to 2950

interface fa 0/24

switchport trunk encapsulation dot1q

switchport mode trunk

on the 2950 port conencting to 2924XL

interface fa 0/24

switchport mode trunk

HTH, rate if it does


Community Member

Re: Connecting 2950 to existing LAN

i agree with royalblues here. you actually cannot enable portfast on a trunk port, you can enable backbone fast though. which cuts through some of the learning stages of spanning tree.

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