MLAG. ISC-link is LAG, MLAG-link is LACP.

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Hi everybody.

I have two x670 switches which are MLAG peers. The ISC link between them is LAG actually. All "clients" connect to this switches with static LAG, but I have to connect one LACP client. Is it possible to use LACP MLAG with static LAG ISC link. So much terms... My diagram below.



As I understand it, config on MLAG peers should be like that

PEER1
enable sharing 16 grouping 16 lacp
enable mlag ports 16 peer PEER2 id 100

PEER2
enable sharing 16 grouping 16 lacp
enable mlag ports 16 peer PEER1 id 100

CLIENT
configure LACP
configure lower LACP priority

Should I configure something else?
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eyeV

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Posted 4 years ago

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Masadi, Ravi, Employee

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There is no such restriction. ISC can be Static sharing and MLAG can be LACP or Static or mixed. On CLIENT also, you need to enable LACP sharing on ports connecting to both X670s
Example:
enable sharing 16 grouping 16,17 lacp
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eyeV

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Thanks!
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Bill Stritzinger, Alum

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eyeV, 

Your configuration looks good on the client side and is totally independent of the ISC link.  The unintended benefit of configuring a single port lag per switch is that you can dynamically add ports without killing the mlag port pairs for the client. 

Bill
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Ted

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I believe I have the same situation but I'm not understanding this fully.  I have an ISC link between my black diamonds (MLAG peer doesn't have lacp configured).  The sharing between them is L3-L4 lacp.  But I have MLAG client (460) set up as a static LAG.   If I understand this right I can change the client to L3-L4 lacp and configure the MLAG peer lacp-mac auto and wouldn't cause an issue - because both ends can support either static or LACP?  Is there any other benefit with LACP vs static like better load distribution than just peering the LAG connections?

Thank you
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eyeV

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Yes, you can change the client sharing to LACP and it wouldn't cause an issue. Morover, I didn't configure the mlag peer lacp-mac auto then I installed LACP. I definetly prefer static, because I like hardcoding everithing.
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Ted

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config LACP on MLAG doesn't seem easy but if I understand it right LACP will detact a bad gbic or fiber cable and will down the LAG.  I'm leaning toward static MLAG LAG too.  I have it currently set this way but our FW images support LACP LAG and was seeing if we could get some real benefit to it.   Thank you.