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ECMP and queue trees

Posted: Thu Jun 08, 2006 2:58 pm
by Bobo_Minky
My question is possibly a silly one, but it is something that i am having a hard time figureing out. If you use ECMP (equal cost multipath routing) with 2 identical connections lets say 1 meg each for arguments sake. What this the total amount of bandwidth that i use at the top of my queue tree. See my reasoning is that it cant be 2 megs because ECMP is making my connection wider so to speak and not higher (meaning i could have 2 users downloading at 1 meg each max but not 1 user downloading at 2 megs since it isnt bonding). This is a fairly important point for me as i dont know how to setup my queue tree limits and how mikrotik manages those limits in a queue tree.

Help would be greatly appreciated

The Bobo_Minky

Posted: Thu Jun 08, 2006 4:25 pm
by Eugene
One thing to think of is that ECMP works not with users, but with _connections_.

Eugene

Posted: Thu Jun 08, 2006 5:04 pm
by fatonk
Yes, Eugene is right this has to do with connections not with users, in your case your client to reach 2 Meg download has to make more tha one connection.

regards.

Posted: Thu Jun 08, 2006 11:18 pm
by Bobo_Minky
sorry to say but i dont think you get what im asking or im not asking it right, when i said users i meant in releation to their queue in the queue tree. If i set the top of my queue tree to 2MB then surely mikrotik asumes that it has 2MB of bandwidth and not 2 x 1MB of bandwidth? So if i make a tree with lets say a parent with 2MB and 2 child queues at 1MB each will that work correctly with ECMP? Or will it cause calculation problems because the connection isnt 2MB high so to speak but 2MB wide meaning 2 simultaneous 1MB connections.

Posted: Thu Jun 08, 2006 11:54 pm
by savage
My first impressions would be 1mb (a chain is only as strong as it's weakest link?). However,

It might be duplicate work, but can you not assign a parent to a interface? I'm not 100% on this.

I'd create a 1mb perant for each interface, with duplicate queues underneath it - one queue per interface... It won't give you a magical 2mb/sec download speed obviously, but it should balance things out fairly well...