WRED - anyone have experience configuring and using this?

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Having TCP congestion on an Metro E circuit.  I'm trying to fix bursty traffic flows
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Ted

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Posted 4 years ago

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Ted

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I believe I won't be able to use WRED, our switches are 8810's with G48Xc, G48Tc and 10G8Xc's.  MSM's are 48c's.  Can someone confirm this for me?  We have a dr 1 gig ETH link connecting our cores to our DR site on an X450a.  Files servers, db servers, vm replication, and monitoring traverse this link.  Is there other TCP congestion options I can use?  The pipe is only partially utilized but does burst up enough to drop extensive packets on the outbound interface.

Thank you,
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Sumit Tokle, Alum

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Ted

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Thanks for the clarification.  Got ideas how to deal with bursty TCP traffic traversing our direct connection?
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Sumit Tokle, Alum

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If it's bursty traffic then I don't think you have more options here instaead of dropping the packet on egress ports.

However, you could increase the port buffer space and see if this would help. 

By default, 25% buffer space is allocated on every port.

configure port <port-list> shared-packet-buffer [<percent>

 
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Ted

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I'll try this.  Thank you again.
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Ted

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Do you info on how much to allow?  As in should I bump it up in increments or skip to 75%?  I don't know what overhead this causes.  Are you aware of any risk with adjusting the buffer size?

Thank you.
Ted