Help!! Need some advice for switch speeds!!

[bbrontosaurus]

Hey all,

A little background info:

Our client PC's are connected to a Cisco Catalyst 2950 Switch with a port speed of 10MBPS/Half Duplex. We also have a server connected to this same switch, but the switch port speed for this server is set to 100Mbps/Full Duplex. The client NIC's are set to autonegotiate. Cabling is Cat5e.


I would like to have the port speed for the client PC's changed to 100MBPS/Full Duplex. I was told the following when I requested the change to 100/Full:

"The reason that we would not want 100MB for PCs is that if there were a rogue NIC card in a PC on a 100MB port it would cause far more problems to the network."


As I don't have a networking background, I need some help in refuting this statement. Can someone point me to some whitepapers that will disprove this statement and/or offer some advice?

Thanks!

 

[spidey07]

Complete and utter BS.

Actually they are causing serious performance problems by running the switch port at 10/half and leaving the client autonegotiate. The client may infact be negotiating to 10/full. Whoever set this up is a bafoon.

All client ports should be set to auto/auto which will allow the clients to operate in 100/full and the switch will be 100/full as well. All servers should be forced to 100/full and their respective switch ports forced as well to avoid the ever rare autoconfiguration problem.

I can't offer any white papers to refute the statement you provided because it is so outrageous and has no basis in reality. The only reason I can see running clients at 10 megabit is because they're using CAT3 cable possibly. But even then you MUST force both sides of the link - this is networking 101...either both sides of the link are auto or both sides of the link are forced. Otherwise you wind up with one side of the link in full duplex but the other is not - essentially killing any performance (can actually show you only < 1 Mbs thruput). Why on god's earth would you run 10 megabit half duplex?

At least do 10/full. But in this day and age 10 megabit ethernet has been dead for about 4 years...everything runs at 100/full.

As for a rogue NIC - inform them that the 2950 has features to control any such traffic and shut the port down.
Please point feel free to copy my response.

good luck

CCNP/CCDP, 12 years network experience.

-edit- Just re-read that statement again. It simply boggles the mind that whoever said that is allowed to touch a network. Seriously.

 

[azev]

how do you to this

As for a rogue NIC - inform them that the 2950 has features to control any such traffic and shut the port down.

Thanks

 

[spidey07]

Configuring port based traffic control:

http://www.cisco.com/en/US/customer/products/hw/switches/ps628/products_configuration_guide_chapter09186a00801a6bb2.html