topic Re: What is LDCP? in Switches, Hubs, and Modems

What is LDCP?

David Söderlund — Mon, 29 Mar 2004 08:02:40 GMT

HP support asked me to switch of LDCP if I was not to use it. What is LDCP?
/David Soderlund

Re: What is LDCP?

cxtwo — Mon, 29 Mar 2004 11:16:32 GMT

Do you mean LACP? Essentially, it's used for forming trunks (combining ports to increase bandwidth) I think its also defined in the IEEE standard 802.3ad. This might be useful for a switch to switch link (if you want a high bandwidth connection in your core) or if you have a server with say 4 network cards that you want to combine into one link to increase bandwidth...

hth

Re: What is LDCP?

Stuart Teo — Mon, 29 Mar 2004 21:46:28 GMT

supplementary: if you're used to cisco lingo, LACP is the IEEE's answer to cisco's propietary PAgP(FEC). cisco also calls a trunk "an etherchannel".

Re: What is LDCP?

Magnus Johansson_1 — Tue, 30 Mar 2004 02:30:12 GMT

Another intresting thing is that LACP is enabled on all ports default, but when I have talked to HP suppurt one of the first things they tells me is to disable LACP on all ports, why not have it disabled default if this is the case?

/Magnus

Re: What is LDCP?

SCOOTER — Tue, 30 Mar 2004 04:00:54 GMT

Magnus,

This is usual a Marketing thingy. Marketing want's to have it enabled but the enigneers do not. And as usual Marketing wins. It's stupid but we have to live with it.

SCOOTER

Re: What is LDCP?

Gonzo Granello — Tue, 30 Mar 2004 04:35:01 GMT

Scooter is right, marketing wins. Maybe not entirely. LACP is supposed to be a automated trunking mechanism and the IEEE spec dictates that it needs to be on by default - otherwise it won't do you much good. Now, if you don't use it, then it makes sense to turn it off since otherwise the ports are blocked longer than needed and the eventlog fills up with lacp msgs.

I would however agree that there needs to be an easier way to turn it off.....

///Andreas

Re: What is LDCP?

OLARU Dan — Tue, 30 Mar 2004 07:41:57 GMT

LACP stands for Link Aggregation Control Protocol.

Re: What is LDCP?

David Söderlund — Tue, 30 Mar 2004 12:36:04 GMT

Tnx to you all. Q answered!
/David

Re: What is LDCP?

Gonzo Granello — Tue, 30 Mar 2004 15:54:55 GMT

David,

points would be nice if it was helpful...

///Andreas

Re: What is LDCP?

Magnus Johansson_1 — Wed, 31 Mar 2004 01:48:54 GMT

It is not hard to turn it of, the problem is that the configfile gets realy long and hard to read...

"no interface all lacp" is the command to use to disable LACP on all interfaces at the same time.

/Magnus

Re: What is LDCP?

Sandy Wise — Thu, 01 Apr 2004 11:44:06 GMT

will the command "no interface all lacp" cause a reboot or require a reboot?

Re: What is LDCP?

Stuart Teo — Thu, 01 Apr 2004 11:49:06 GMT

Turning off passive LACP will not need a reboot. I'm not sure why you were asked to turn off passive LACP. I leave them on and everything works fine. Of course I have an occasional scenerio where I may have a serve attempting to negotiate an LACP trunk. By leaving them turned on, the sysadmins don't have to call me.

Re: What is LDCP?

Magnus Johansson_1 — Fri, 02 Apr 2004 00:52:00 GMT

There is a lot of error-messages filling up the logs, that makes it harder to troubleshoot.

The recomendation came from at least two different persons from HP-support when I have started cases there.

Nowdays we allways turn it of.

/Magnus