topic Re: Changing Speed in Operating System - OpenVMS

Changing Speed

BRUCE BROWN_2 — Mon, 07 Apr 2008 14:09:39 GMT

Hi

I want to increase the speed on 3X-DEGXA-TB Nic
from 100 full to 1GB. The node is a ES47 running VMS 7.3.2.

How do I accomplish this?

Many Tks

Bruce

Re: Changing Speed

Ian Miller. — Mon, 07 Apr 2008 14:41:06 GMT

See LANCP SET DEVICE/SPEED

Is the device not set to autoneg ?

Re: Changing Speed

Peter Zeiszler — Mon, 07 Apr 2008 14:45:51 GMT

Be aware that sometime when you set the speed on the card you have to set the speed on the switch or it will lose communication. Doing auto negotiate together will normally pull the highest matching speed but sometimes you have to manually set it at both ends.

mc lancp show dev /param

Look at Line Duplex and Line Speed. That should show the current settings.

mc lancp
help set dev /speed
help set dev

Re: Changing Speed

Peter Zeiszler — Mon, 07 Apr 2008 14:48:46 GMT

Forgot to mention - you can also set the speed at the >>> prompt. Remember to set there too if you need to. If you try "set ewa0_mode" see what options it gives you. (I think thats the boot prompt command)

If your only connection to the system is through your network and you lose your network, then be ready to goto the console.

Re: Changing Speed

Robert Brooks_1 — Mon, 07 Apr 2008 22:55:58 GMT

Standard refrain -- For virtually all modern ethernet cards connected to a modern networking switch that is running a relatively recent version of VMS with current patches, your easiest route to happiness is simply setting
the relevant console variable to autonegotiate and setting the relevant port to autonegotiate.

The above advice comes from the guy who writes and maintains the ethernet drivers for VMS (that's not me; I'm just passing along his learned words). V7.3-2 with current patches falls under the "relatively recent version of VMS" caveat I noted above.

If this doesn't work, the ethernet driver guy would like to hear about it, since it has worked pretty hard to make this as transparent as possible. Note that nowhere in the above suggestion is there a need to fiddle with anything via LANCP.

-- Rob

Re: Changing Speed

John Gillings — Sun, 13 Apr 2008 23:39:18 GMT

Autonegotiate is effectively mandatory for GB ethernet. If it's not enabled you get no flow control, which will cause things to break.

IMHO it's silly to not enable autonegotiate on all your 100MB ethernet adapters, switches, hubs, routers, etc... (I've seen WAY too many problems caused by duplex mismatches resulting from hard set adapters), but ultimately it's the choice of the system manager.

But, Gigabit is a whole new ballgame. Autonegotiate is not negotiable! Just turn it on.