Cisco 3020 switch connect to to cisco 6509

[Dsmit]

I have a C-class enclosure with a cisco 3020 switch installed, I am trying to connect it directly to a Cisco 6509 switch, but cant get the trunk up,I get a link light on the 3020 side but not the 6505, checked fibre, I am however able to connect the 3020 to another switch and that work and can connect the 6509 to other swithed using same port and that alos work, wondering if there is an incompatability issue between the to swithes, has any one else experience something similar, thanks

[OLARU Dan]

Check both transceivers at the ends of the link are configured 1000Mbps FDx, or that both are in AUTO and are not administratively shutdown. Encapsulations used should be the same and also Flow Control setting should be the same for both transceivers.

[OLARU Dan]

Also you can't connect LX to SX transceivers, SX transceivers would not work on Singlemode fibers, LX distance specs say 550 meters on Multimode fibers and usually they require Mode Conditioning Patches.

Check and clean the ends of the patcords and of the fiber pigtails in the f/o patch panels.