les 100

[hughzy]

Hi can anyone help me. i have a 3550 connected using a fast ethernet port and then going over a les 100 line to a cat 6500 and into a fast ethernet module. they are configured with switchport trunk encapsulation dot1q,switchport mode trunk.

problem is the port on the 6500 keeps shutting down when data goes through it.

[lgijssel]

Is a les100 some kind of high-speed leased line? In that case, you might have troubles with the dot1Q frame tagging.

Please try to configure the ports as access ports to see if the link on the 6500 remains up.

There is no need for a trunk link. You have two L3 capable switches and could setup a routed connection between them. You can do this by defining a separate IP subnet and VLAN belonging only to this link.

Regards,

Leo

[hughzy]

Yes it is, thanx i will give it a try

[#4]

hugh

I would check with BT to ensure the equipment supplied supports the dot1q etc and is set correctly.

the LES 100 unit is just an ethernet fibre driver

I would suggest also speaking to the CISCO health team who can help.I can forward you the details if you require.