Connection between 6509E and 3750

saurabh1969 · ‎04-09-2008

I am trying to connect the new 6509E switch with 3750 using SFP module. 6509E is running 12.2(33)SXH and has a SUP720-3B and 3750 is running IOS 12.2(25)SEE2. We can't seem to establish the connectivity using port-channel or single port. Port is properly configured on both sides i.e. trunk encapsulation dot1q and switch mode trunk. What could be the problem? The switches are only 30 meters apart and we are running multimode 62.5/125 fiber between them. Is that too short and do we need to use the attenuator?

jcoke · ‎04-09-2008

That depends on what transceivers you are using in the switches. On a more basic level, are you sure the media (cable plant *and* jumpers) is good?

saurabh1969 · ‎04-10-2008

We are using GLC-SX-MM and media type on both side is SX or SFP SX. On 3745 it is 1000BaseSX SFP and on 6509E it is SX.

bmarms · ‎04-09-2008

are you using GLC-SX-MM SFP's? have you tried switching the TX and RX fiber ends at your cable plant verifying they are not backwards?

saurabh1969 · ‎04-10-2008

How do you change the ends when they are pre-made and already crimped?

saurabh1969 · ‎04-10-2008

Yes, I am using GLC-SX-MM SFP.

saurabh1969 · ‎04-10-2008

Yes they were and once I reversed them the link came up but went down within few minutes saying (err-disabled)

bmarms · ‎04-10-2008

can you post the config of the gig interfaces in question on your 6509 and your 3750?

Jason Fraioli · ‎04-10-2008

If you are seeing err-disabled, then you might have portfast enabled on your trunk along with bpduguard enabled. Try disabling bpdugaurd "no spanning-tree portfast bpdugaurd". Then clear your err-disabled state, "clear err-disable vlan". Then do a shut, no shut, on the interface.

Showing a config would definately help.