[reSIProcate] DUM SRV failover behavior

[Jason Fischl]

If you use UDP, it will take 32 seconds for the transaction to fail
which will result in a 408 response being generated and sent up to the
TU. The next time you try this transaction, it will not use the A
record that previously failed.

On 10/26/06, Shaun Dawson <scdawson at gmail.com> wrote:
> Jason, resiprocate devels,
>
>   Sorry to revive this issue, but there's something that I still don't
> completely understand.
>
>   Does this mean that if I am willing to wait more than 32 seconds for
> an SRV failure in UDP, that DUM _will_ fail over?  Or is that not the
> case?
>
>   It seems that in my app, I am seeing the latter behavior, when I
> would expect the former.
>
> thanks!
>
> Shaun
>
> On 8/7/06, Jason Fischl <jason at counterpath.com> wrote:
> > Under what circumstances are you trying to failover? If you are using
> > udp and the first server is not responding at all, the timeout will
> > take 32 seconds to occur so you will never fail over.
> >
> > If you use a connection-oriented protocol, you will get an ICMP error
> > when you try to connect and it will immediately failover. It would
> > failover with UDP if the server sent an explicit error.
> >
> > We've considered changing this behavior so that UDP would failover
> > sooner but this would imply not waiting the full 64*T1 for a timeout.
> > Note that the DNS caching and blacklisting will ensure that the failed
> > server is not retried on a subsequent transaction.
> >
> > Jason
> >
> >
> >
> >
> > On 8/7/06, Shaun Dawson <scdawson at gmail.com> wrote:
> > > All,
> > >
> > >  I've been having trouble getting the DUM to fail over to a secondary SIP
> > > proxy using SRV records.  Before I get too crazy trying to to poke further
> > > into the problem, does anyone know that this expressedly does or does not
> > > work?
> > >
> > >  thanks,
> > >    Shaun
> > >
> > > _______________________________________________
> > > resiprocate-devel mailing list
> > > resiprocate-devel at list.sipfoundry.org
> > > https://list.sipfoundry.org/mailman/listinfo/resiprocate-devel
> > >
> > >
> >
>