Link aggregation on a procurve 2848 switch

[Peter Thorn]

I apologize up front for perhaps asking a newbie question...
I have a procurve 2848 switch and have updated the firmware to the latest version (I_08_98.swi) and rebooted it.
As my mac os x xserve (10.4.7) supports link aggregation and the newest firmware for the switch also should support it, I would like to use that feature, but I get the message (on the server) that the switch isn't configured to use link aggregation or doesn't support it.
How do I activate it? is LACP the same? - if so, how do I activate that? (the command in the manual "interface c5 [or whatever portnumber] lacp active" returns "invalid input: interface").

TIA,
Peter

[Mohieddin Kharnoub]

Hi

For Port Aggregation configuration steps, check this:
ftp://ftp.hp.com/pub/networking/software/Mgmt-Oct2005-59906023-Chap12.pdf

BUT
forget about C, just remove it and put the port number, C is for the modular switches.
So configuarion should be like this:
2848(config)#trunk 1-2 trk1 --- this creates a trunk of ports 1 and 2 with trk1 name.

Then you should add this trunk to a Vlan that you want your server to be in.

2848(config)#vlan 2 untag trk1 --- assuming the server should be in vlan 2.

Note:
1- You can change the Trunk mode from the default TRUNK, to LACP or FEC (cisco proprietary).
2- All ports by default has passive LACP.

Just read the configuration steps in the link above and see whats suitable for your setup.

Good Luck !!!

[Peter Thorn]

Thanks for the quick reply
Please be patient, as I have problems understanding it fully :-)

2848(config)#trunk 1-2 trk1 --- this creates a trunk of ports 1 and 2 with trk1 name.

- the (config)# part of the command above - I assume that it refers to the CLI prompt when I telnet into the switch? (I ask just to be sure I don't have to access into some config mode first - the examples in pdf isn't stringent in its use)
- do I have to trunk the ports when I use LACP? From what I read from your reply, I have to trunk the ports first, then convert them to LACP?

2848(config)#vlan 2 untag trk1 --- assuming the server should be in vlan 2.

- this is where it really shows that I'm a newbie... It is the only switch on the network, and only one VLAN exsist, so is that part neccesary?

Thanks again,
Peter

[Mohieddin Kharnoub · Accepted solution]

Hi

I will try to explain in details :)

-Trunking: is grouping more than one physical port (at least 2) to form a logical port (Trunk), used for getting higher speed, redundancy and load sharing.

-Trunking uses many protocols like the standard one LACP IEEE 802.3ad , and Cisco one.

-Usually trunking used with server by teaming multiple ethernet cards to the switch, and they usually recommend to keep LACP passive on server trunks.

-LACP has 2 modes, Passive (default) and Active.

Now
for your case, be sure what do you want to do exactly, then read the link i gave you before, it explains in details how to do it.

Note:
To learn how to configure the switch ? so yo ucan know that (config)# is a prompt, read this:
ftp://ftp.hp.com/pub/networking/software/Mgmt-Oct2005-59906023-Chap04.pdf

I hope that was helpful, anyway if you have any problems, then this is the right place to share it with the people.

Don't forget to assign points to posts that hepled you.

Good Luck !!!

[André Beck]

Hi,

> -Usually trunking used with server by teaming
> multiple ethernet cards to the switch, and
> they usually recommend to keep LACP passive
> on server trunks.

> -LACP has 2 modes, Passive (default) and
> Active.

I first thought LACP passive as provided by default on access layer ProCurves would be a good idea. Sadly it isn't, due to the braindead implementation. If a number of ports form a LACP trunk due to passive LACP triggered by a host talking active LACP, the trunk doesn't inherit essential port parameters, especially not the VLAN port assignment. It always ends up untagged in VID 1 - something completely useless except in trivial networks. I call this BAD - broken as designed. But it's consequent, considering the identical behavior of dual personality ports upon plugging/removing an SFP. Consequent, but still a PITA.

Andre.

[Peter Thorn]

Just to follow up with the solution, so others might use it:
- first telnet to the switch
- then enter config mode by writing "config"
- activate lacp on the appropiate ports eg. "int e 33-34 lacp active" (which obviously is activation for port 33 and 34)
- check that it works by writing "show lacp" which should list if the port is active or passive.

That's it - no need for manual trunking.

Peter

[Jason Buscema]

I'm currently testing this feature out on 2 G5s running 10.4.7. I've got a 4108gl and lacp active on the ports. I see the lacp status is active, it establishes a dynamic trunk group and it has a lacp partner for my two machines. So far so good. My issue has to do with throughput. I was expecting an increase in bandwidth between the two machines w/ link aggregrate enabled, but the speed is just the same if I was to go back to a single nic. Am I missing something? I have not rebooted the switch.

[Peter Thorn]

What does it say in the Status field in the Network setting on the server - does it show both connections with green light and no problems?

Peter