Network Duplex and Speed settings

Hello gurus,

I just want to know which is better?

Our Switch and Server can run 1Gbps but we want to limit the speed to 100Mbps due to limitations. I want to know if which one is much better coz be encounter some problem with both end.

Senario 1:
Switch: Auto-Negotiation
Server: 100/ Full duplex

Problem: Sometimes the Switch set the connection to 100Mbps Half-duplex, causing some Late collisions.

Senario 2:
Switch: 100/ Full duplex
Server: Auto-Negotiation

Problem: Sometimes the Server set the connection to 100Mbps Half-duplex, causing some FCS errors.

Senario 3:
Switch: Auto-Negotiation
Server: Auto-Negotiation

Problem: Cannot use 1Gbps Full-duplex

Senario 4:
Switch: 100/ Full duplex
Server: 100/ Full duplex

Problem: Any expected errors??? not yet tried

Please Advise

I would have thought "Scenario 4" would be the obvious choice. Also, on some switches, you can rate limit individual ports (independently of negotiated or preset speed settings) I can do this on my Netgear GS748T SmartSwitch.

Scenario 4 is right. As a rule of thumb, never have the port speed/mode fixed at one end of the link and auto at the other; this causes collisions and interface flapping as you have noted. Either fix at both ends of the link or have both ends auto