speed-duplex 100-full

[aitmoulay]

Hello everyone,

I want to know the correct configuration to the port level
Ethernet switches HP procuvre, regarding the channel
Communication:

Is it advisable to leave the port by car, or configure
by speed-duplex 100-full (ports of switches are connected to
IP phones connect to their PC tower).

And for inter switch connections is what the recommendation. The
left in the car or the specified speed and mode.

Thank you for your advice.

[Michael_Breuer]

Hello,

you can leave both ends in autoconfiguration. That means that speed will be auto sensed and duplex mode negotiated. Just in case of problem you should think about setting a fix value. If you set it to a fix value you have to ensure that both ends are set to the same value to avoid duplex mismatches.

Cheers,

Michael

[rick jones]

I have "never" had autonegotiation problems with ProCurve switches, but then I may lead a charmed life. Still, unless and until you *know* that one side or the other does not autonegotiate correctly and cannot be repaired to do so, my personal opinion is to leave both ends at autonegotiate enabled. More in the attached boilerplate.

[Pieter 't Hart]

Hi Rick,

I second your stand to use auto first and only when problems are detected or suspected use fixed settings.

Nice text in your "boilerplate", i'll keep this for reference.
Only I think the text is not complete.
auto + auto = hapiness isn't allways the situation.
It doesn't handle connecting a 100-auto to 1000-auto port.
If the 100 negotiates from 100 down, and the 1000 from 1000 down, the may miss the wanted configuration.

Also some vendors they negotiate up instead of down (but it's about procurve in the original post)

[aitmoulay]

Ok, thank you very much,

Voila now to ports interconnecting switches of it are all auto-negotiation, for cons I switches which have ports 1G, and the park there are computers with PC card 100 and network with other network cards 1000 so I put all the ports of switches that connects posts by speed-duplex 100-full. For all runs with 100, is that I leave the configuration as AC or preferably I change ports in auto-negotiation?

[Richard Brodie_1]

"If the 100 negotiates from 100 down, and the 1000 from 1000 down, the may miss the wanted configuration."

That isn't how autonegotiation works though; the devices exchange capability data, and the highest common operating mode is picked. They don't jump around trying different speeds.

Unless one of the devices has a bug in the autonegotiation, it should just fine.

[Pieter 't Hart]

Hi Richard,
You're Right.

[rick jones]

Well, the boilerplate was first written before 1000Base-T existed :) That bit about gigabit was a later afterthought.

I've always thought that there were two (or more) separate things going-on:

1) autosense - pick the speed used on the wire
2) autonegotiate - pick full or half duplex

but it does seem very common to lump those two things together.