Re: [lvs-users] UDP persistence woes

To: " users mailing list." <lvs-users@xxxxxxxxxxxxxxxxxxxxxx>
Subject: Re: [lvs-users] UDP persistence woes
From: Graeme Fowler <graeme@xxxxxxxxxxx>
Date: Tue, 18 Nov 2008 17:07:55 +0000
On Tue, 2008-11-18 at 10:40 -0600, Michael Pfeuffer wrote:
> Thanks for the quick reply.  Unfortunately, using 'sh' didn't make any 
> difference.  FWIW, the test traffic is all coming from the same source 
> address, to that may explain why.

Yep, that would explain it.

You could artificially reduce the UDP protocol timeout for testing:

ipvsadm --set <tcp> <tcpfin> <udp>  (see man ipvsadm for info)

but you can't make it less than 1 second.

Also, because UDP is stateless, a "session" is viewed as traffic
arriving from $host with $source_port to a given VIP/Port within the UDP
timeout detailed above. This causes problems with SIP signalling data in
some cases because it has a tendency to be sourced from port 5060, to
port 5060 and is quite regular.

If you have a larger spread of clients, over time things will become
roughly balanced according to your RS weights.


<Prev in Thread] Current Thread [Next in Thread>