Ethernet Switches & Routers

Video: Configuring Dynamic Link Aggregation Groups (LAGs)

by on ‎06-20-2016 07:41 AM - edited on ‎03-20-2017 09:42 AM by Community Manager (652 Views)

In this video, we'll show you how to configure dynamic Link Aggregation Groups (LAGs) on Brocade campus switches.

 

 

Video Transcript:

 

0:00 - This is brocade campus feature explainer series, I’m Terry Henry. This time around

0:03 - we're going to talk about dynamic link aggregation. So dynamic link aggregation

0:08 - uses 802.3ad as a standard which the protocol is LACP. So the way it

0:16 - works is that one end will send a LACP control packet or a LACPDU to the remote

0:24- end and it has to get a reply back in order to bring the port up. So the

0:29 - benefit to using dynamics is that in a static environment the once you create

0:36 - that static LAG and deploy it if the other end is not

0:40 - deployed or the cables plugged into the wrong place or the other end is

0:45 - misconfigured you can create a loop and eventually bring your network down

0:49 - whereas dynamic LAG and LACP will help check the other end

0:54 - make sure that it's plugged into the right port to make sure that it's good

0:57 - the configuration is correct and then but the port in a forwarding state so it

1:01 - protects you against those sort of issues.

1:03 - So in order to configure this we're going into config t, we’ll have to do both ends

1:09 - here, so we create our LAG you just say LAG you give it a name so a descriptive name

1:15 - always help so that you can look at it later

1:18 - so we're going to call it To7250-2

1:22 - so we're going to identify what the remote end is this lag. And then you've

1:26 - got a couple options you can see a dynamic which is what we are going to

1:30 - create you've got to keep alive which would be used

1:34 - instead of udld in a multi-vendor environment usually and lastly you can

1:39 - create a static if you wish but would you were just going to create dynamic.

1:43 - And then you can you can assign an ID here if you want but I’m just going to

1:47 - let the system give me a

1:49 - generated ID. So then I’m in my LAG sub configuration here so we need to do

1:55 - a couple things

1:56 - there's many many options here

2:00 - but what we what we must configure is the port's, a primary port and then

2:07 - deploy it otherwise the other things are just optional. So we will assign our

2:11 - ports to it supports e 1/2/1 and then I can make into a range here or I

2:18 - can just do it another port so I can put in multiple ports so I’m going to say

2:22 - e 1/2/3 because they're not in a group together if it was you know 1/2/2

2:30 - 1/2/3 I could have done that to but in this case I'm just going

2:34 - to add those ports and then I have to have a primary port so that the purpose

2:39 - of the primary port is a couple things one is it's where your primer your

2:43 - broadcast on unicast and multicast go

2:46 - and secondly it is where the configuration goes. So if I go in and

2:51 - shut down the primary port under the interface

2:54 - it's going to shut down all the ports in the LAG so it is the controlling port

2:59 - if you will.

3:00 - So we're just going to set a primary here and then you give it the port

3:05 - number so you'll notice that there's no E here, you don't do a primary ethernet

3:09 - 1/2/1 so that's just something to watch out for.

3:15 - And then lastly we need to deploy it so we just do a deploy here and it tells me

3:21 - that it's deployed successfully.

3:23 – Ok, so I'm not worried about a loop even if my ports were up at this point

3:27 - they're never going to go into forwarding state because the remote end has not yet

3:31 - been configured so if we do a show lag, well just do a show lag

3:38 - I could have done a specific one so what we see here is we built this lag

3:43 - To7250-2, its dynamic and it's deployed.

3:47 - Here's my ports 1/2/1 and 1/2/ 3.

3:51 - So I got two ports, the primary port is 1/2/1

3:54 - the key here you could specify key if you wish I let the system create a key

3:59 - for me

4:00 - and then we can look at our ports so in this case my ports are down there

4:03 - physically unplugged at this point so I don't see a speed and duplex etcetera and

4:09 - then under the configuration here

4:11 - the operational state is down.

4:15 - So there's a couple of different choices for operational state so the next thing

4:19 - I'm gonna do is plug those cables in and we'll see what happens.

4:23 - So keep in mind that the remote end is still not configured at this point,

4:30 - so those ports should not go into an operational state and they do not

4:35 - so you'll see here that the operational state now that those ports are up is

4:40 - either they're up and the state is blocked so they're lacp blocked. There blocked by link

4:44 - aggregation and they're in inactive state.

4:47 - So if we actually go and look at one of those interfaces show interface

4:51 - e 1/2/1 for example the port is up the line protocol is down because it's

4:59 - lacp blocked and we can see that how long it's been blocked for it so it's

5:03 - been lacp block for 28 seconds as of right now.

5:07 - You'll also see down here is a member of an active trunk port and who the primary

5:14 - port is and what it’s configured for so active versus configured in these two.

5:19 - Ok so we've got one end up and running it's waiting for the remote side to come

5:24 - up and send an LACP reply packet so I'm going to move my console over to the

5:29 - second switch and we're basically going to build the same configuration on the

5:34 - remote end. So in config t

5:37 - we will do a lag

5:40 - To7250-1 so I remember what it is and assign it is dynamic

5:47 – ok. So now again we put our ports in we have this we're using the same ports in

5:52 - this case e 1/2/1

5:55 – 1/2/3

6:02 - we assign our primary 1/2/1 again no E there. And then lastly we

6:09 - deploy it, so it says it supports successfully. So now if I look at the

6:15 - show Lag output so I have my lag deployed dynamic it's deployed

6:23 - here's the ports, port count 2, here's the primary port its hash based same key

6:29 - this key of course is a locally significant so it doesn't matter if the

6:34 - key does or does not match on across the two sides that is only for the local

6:38 - device to differentiate group supports from each other and then we look at

6:43 - our ports 1/2/1 and 1/2/3 so they are up and forwarding full-duplex 10 gig trunk

6:49 - number one VLAN ID. And then if we look at the ports

6:56 - we can see that they are now in an operational state so this means that

7:01 - that my trunk is now up and working as opposed to it being inactive

7:06 - meaning lacp blocked or down

7:10 - meaning the ports are physically down for whatever reason and then lastly if

7:15 - we look at the partner info and pdu statistics we can see that

7:21 - we're sending and receiving LACPDU so we know that that's

7:27 - operational and then if I look at the interfaces 1/2/1 rather

7:33 - than saying lacp blocked under protocol

7:37 - the port is now up and up. We see active trunk here with the primary port and

7:42 - configure port with the primary port so that's it relatively straight forward

7:48 - thanks for joining.