Switch

[CSCO10320953]

You are about to configure fast ethernet on an adapter to connect to a switch. What are valid configuration pairs?

Switch: Autoneg On -?Client: Autoneg On

Switch:?100HD -?Client: Autoneg On

Switch:?100FD -?Client: Autoneg On

Switch:?100FD -?Client: 100FD

[ankbhasi]

Hi Friend,

The best combinations are

Switch: Autoneg On -?Client: Autoneg On

Switch:?100FD -?Client: Autoneg On

Switch:?100FD -?Client: 100FD

Any of the 3 above combinations work fine. But sometime auto auto on both sides does not work well due to negotiation problem on link so you can keep any of the 2

Switch:?100FD -?Client: Autoneg On

Switch:?100FD -?Client: 100FD

and it will work fine.

HTH

Ankur

*Pls rate helpfull post

[royalblues]

Friend,

I would like to add to the above post, that if you hard code any one side and keep the other side to autonegotiate, the link always will work on Half Duplex.

So i dont think it is a best option.

HTH

Narayan

[glen.grant]

I would disagree with the switch as 100/FD and the client as auto this creates a speed/duplex mismatch as the client side will default to 100/half. This will cause problems ...

[jeff.teoch]

If you hard code on switch, it's best for you to hard code on client as well. As for servers, it's best practice to hard code both sides.

[mahmoodmkl]

Hi

I agree with royalblues as if u hardcode one end and leave the other end to auto it will be half-duplex.

Thanks

Mahmood

[schm196]

Auto/Auto and 100FD/100FD are the only valid configurations, with preference to 100FD/100FD fix configuration when using third-party NICs that may run into auto-negotiation issues. Forcing one end to a fix setting causes alignment errors, FCS errors, or late collisions on the interfaces if the other is left to attempt auto-negotiation. See http://www.cisco.com/warp/public/473/53.shtml#SpeedDuplex_mismatch for the official take on this.