We have 2 x 6500's and have a prefab fibre cable with SFP connectors. We plug GBIC's into the 6500's and the SFP cable into the Gig1/1 port which are the SFP ports but the ports do not come up.
Does the fibre need to be crossed or can we enter some mdix config commands to deal with this?
Gary
Gary,
To connect any two GBICs (or SFP modules), you should connect TX on one switch to RX on another. Just think logically - one fiber SENDS a light, so, another should RECEIVE it.
Practically, fiber patch cords are color coded. So, if on the one end you connect "Black/White", then on another end you should connect White/Black.
Good luck,
Mike
The 6500 has an mdix auto command in the gig interfaces but it does not do anything.
Is the only option to alter the cables.
Gary,
You can not "swap" TX and RX signals on the Fiber GBICs. Physically you have light source on the one jack, and light receiver on the another. Just swap cable connectors to have TXRX for the both ends and it will work.
Mike
I can't speak for any particular cables however FO patch leads are usually "crossover".
This is what most people want since the task is often to connect two identical switch ports.
"Straight through" patch leads would have to be specially ordered.
If you think about it you always (well pretty much) have an odd number of leads.
I am making the rest up.
Port - Patch - Port ---- 1 lead Port - Patch - Infrastructure-cable - Patch- Port --- 3 leads Port - Patch - Infra-cable - Patch - Infra-cable - Patch - Port --- 5 leads etc. etc.
So if they are all crossover they you always get the right thing and all ports are identical.
Not so bad really.
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