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Re: is odd number of links in lag group ok


From: Ben Cannon <ben () 6by7 net>
Date: Wed, 16 May 2018 16:32:34 -0700

While it goes without saying that you need the same (can be 5!) number of links to each router in a multichassis LAG, 
what isn’t so obvious are things like port groups etc.

If you have an oversubscribed platform, you might need to look at running each wire in a LAG to different port groups, 
and then look at things like switch ASICs and span those as well.

Even try to span diverse slots/modules if you can.

But 5 6 or 4 per chassis shouldn’t make a huge difference. 

-Ben

On May 16, 2018, at 3:48 PM, Wayne Bouchard <web () typo org> wrote:

As others have noted, there can be implementation specific issues that
you can't necessarily predict but most typically when I hear "odd vs
even" discussions, usually the caveat is not a trunk but a redundant
connection. Putting three links on router A and two links on router B
obviously doesn't work well.

On Tue, May 15, 2018 at 10:15:19AM -0500, Aaron Gould wrote:
I have (2) 10 gig links bundled in a lag to my upstream internet provider.
and we need more internet capacity.  Is it cool to add a third 10 gig to my
existing 20 gig lag internet connection?



I'm asking since I heard in the past something negative about odd numbers of
lag members.  .but I also have heard that it's not a big deal.  Let me know
please



-Aaron





---
Wayne Bouchard
web () typo org
Network Dude
http://www.typo.org/~web/


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