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auto vs 100/f

We have been debating whether to just force the devices (servers, workstations, etc.) and the catalyst switches to 100/F ... or just let them be in auto mode.

What would you guys recommend?


Re: auto vs 100/f

I typically recommend hard coding 100/full or 1000/full on servers and the occasional stubborn workstation (it sometimes does happen). Workstations will be fine set to auto negotiation. It can be a lot of extra overhead going to every workstation on a network and configuring the settings especially if it is a large network.




Re: auto vs 100/f

"I typically recommend hard coding 100/full or 1000/full on servers"

for 100/full yes but for CopperGig interface,

I would strongly recommend against this,

especially on Linux Operating Systems. I

normally set the switchport to auto/auto

and the CopperGig interface on the Linux

server will be 1000/full

Using ethtool, you can see below:

Settings for eth13:

Supported ports: [ TP ]

Supported link modes: 10baseT/Half 10baseT/Full

100baseT/Half 100baseT/Full


Supports auto-negotiation: Yes

Advertised link modes: 10baseT/Half 10baseT/Full

100baseT/Half 100baseT/Full


Advertised auto-negotiation: Yes

Speed: 1000Mb/s

Duplex: Full

Port: Twisted Pair


Transceiver: internal

Auto-negotiation: on

Supports Wake-on: g

Wake-on: d

Link detected: yes

Hall of Fame Super Blue

Re: auto vs 100/f

I totally agree with Mark on this and just wanted to add that with clients especially if you have laptop users it is often a real pain to hardcode them because users will then connect them into their home network to VPN into the office and they just won't work.



Re: auto vs 100/f

It is just way too much work unless you have like 25 users in your network . If you hardcode like previous posters said you have to go to every single user workstation and server and hardcode those also to 100/full. For the most part auto works pretty well nowadays. Also you would have to make arrangements for whoever installs all your new laptops and desktops that anything new would have to be hardcoded to 100/full before it goes out to the user community.