LACP connected host --- two tier MLAG --- LACP connected host

[enrico_kunert]

Hi all,

we have the following testsetup and i have a question regarding the different ping behavior as shown below... plz have a look and thank you in advance

two tier MALG with two connected LACP Hosts/switches

config as shown below....

testcases.....

thx

[Roy_Noh]

I guess there should be no loop based on your scenario, but a loop may produced by mistake on configuration or by edge switches. EXOS user guide introduces some cases and how to prevent it with ELRP egress port disable with MLAG configuration.

http://documentation.extremenetworks.com/exos_16/EXOS_16_2/Troubleshooting/c_elrp-egress-port-disabl...

[enrico_kunert]

Hi Roy,

thank you for your help.

ELRP just need to be configured at non MLAG ports, right?

greetings

[Roy_Noh]

Enrico, Sorry for late response.
Yes, I think there should be no issue if you stick to your plan.
ELRP can be helpful to detect a temporary loop just in case.
You can easily be noticed by switch logs if there's any loop.

[enrico_kunert]

Hi Roy,

I have tried to show this in this picture below - we want to migrate the EAPS Setup (BLACK) to the MLAG Setup (RED) without any interruption if possible

1. first we have the EAPS setup (black connections) - some devices are connected with LACP some just have a single connection

2. we want to configure the MLAG setup with ports shutdown - break up the EAPS - and migrate the attached devices step by step to the MLAG

to aviod loops we decided to shudown one port of any LAG/LACP connected device (e.g. the dual-homed Access Switches ) so we just have to add a single connection to the MLAG ports by adding them like this (enable mlag port <> peer isc-test-2 id 71)

so i think we dont run into any problems , if half of the MLAG ports (lsc-test-1 - lsc-test-2) are configured with (enable mlag port <> peer isc-test-2 id 71) and the others without - as long as we ensure that we do not have any LACP dual-homed devices connected to MLAG ports (lsc-test-1 - lsc-test-2) without an enabled mlag port (enable mlag port <> peer isc-test-2 id 71) configuration.

greetings