Spee and duplex configuration

[henry.saravia]

I need any recomendation interconnecting lan switches to server, what is the recomendation about the speed and duplex?, is better force this parameters or auto mode?

[Edison Ortiz]

Please refer to these documents:

http://www.cisco.com/en/US/tech/tk389/tk214/technologies_tech_note09186a0080094781.shtml

http://www.cisco.com/en/US/products/hw/switches/ps700/products_tech_note09186a00800a7af0.shtml

HTH,

__

Edison.

[Rui Carlos Antunes]

Usually forcing speed and duplex both on the switch and on the server is the way to go.

[Leo Laohoo]

Rule of thumb I am using.

Force duplex and speed (both sides) settings when switch is a 10/100/100Base (aka Triple speed) but server is a DUAL speed. This is also true when your server is triple speed and the switch is only dual.

Autonegotiate when switch and server is Triple speed.

Hope this helps.

[Danilo Dy]

For devices that have static IP Address and in fixed location (specially critical devices like routers, firewall, servers, etc), I hardcode the speed/duplex. Except for those devices that don't support hardcoding the speed/duplex (e.g. GE interface of non-Cisco devices like PacketShaper, HP Unix).

From what I understand in the past, there is no standard for auto-negotiation thats why every vendor set their own standards for auto-negotiation. Do take note that this is in the past.

I have experienced that devices from same vendor configured in auto-negotiation even using good quality cable experiences speed/duplex mismatch overtime or during maintenance (IOS/OS upgrade, System Reboot). You will be surprised that I experienced that between a Cisco Catalyst Switch and Router after two years in production and nobody touch them, suddenly they have a duplex mismatch :).