Configuration of port sharing (LAG) member ports

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Setting up LAGs is dead easy in XOS.  But, I have a couple questions about it:

1:  When I take a previously used port and add it to a LAG using port sharing, what happens to whatever VLAN egressing configurations that port had before I added it to the LAG?

And, there's a corollary:

2.  It used to be a good practice to match LAG port VLAN egressing configurations on the individual member ports.  Is this still a thing in XOS?
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Jesse Ohlsson

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Posted 2 years ago

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Patrick Voss, Alum

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Hello Jesse,

Here are the answers to your questions:

1) A majority of the configuration is removed once you add it to a lag. It should prompt this when the port is added.
2) If you are referring to VLAN configuration, I would leave the ports as unconfigured. This way you can prevent an traffic related issues should the lag split.
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Jesse Ohlsson

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Thanks, Patrick.  That simplifies things considerably.  I like simple.  Makes me look like I know what I'm doing
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Erik Auerswald, Embassador

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Hi Jesse,

regarding question 2, EOS and EXOS differ in this regard. While an EOS LAG automatically falls back to individual ports if the LAG cannot be formed, EXOS uses the LAG (port sharing) even if the LAG does not form.

There is a new LACP Fallback feature in EXOS that allows one port in a dynamic LAG (port sharing) to come up even w/o receiving LACP. But this still uses the LAG configuration, not the physical port configuration.

While EOS uses an additional logical port lag.0.X for the LAG, EXOS re-uses the handle of the physical master port, disabling configuration of non-master member ports. Thus EXOS cannot have differing configurations for the LAG and its ports.