[Freeswitch-users] Live Upgrade Techniques

[John Dalgliesh]

On Thu, 11 Jun 2009 at 22:57 -0500, Brian West wrote:
> On Jun 11, 2009, at 10:35 PM, John Dalgliesh wrote:
>> On Thu, 11 Jun 2009 at 16:33 -0400, Michael Giagnocavo wrote:
>>> 
>>> Well, if you're running multiple machines, waiting for it to drainstop
>>> isn't that big of a deal unless you're in some sort of hurry, right?
>>> Give it an hour or so to drainstop, then kill 'em.
>> 
>> Yes that's exactly what I'm trying to do. The problem is some people will
>> only try one IP address.
>
> Clients that don't properly implement SRV/NAPTR and fail over need to be 
> smacked.  :)  (not customers but software that fails to do that)

Yes I'm sure much of their software can do this but it has been set up for 
static numeric IPs. And getting the IP changed is a week-long process for 
some customers!

>>> Would it not be simpler to try to do something with re-invites or REFER,
>>> assuming your endpoints support it?
>> 
>> That was actually plan A. I already added a property in sip_profile called
>> failover_redirect, which specifies another server to try if FS can't
>> allocate any more sessions (e.g. too busy, paused, shutdown asap, etc.),
>> by sending back a SIP 302 Moved Temporarily response, instead of 503 Max
>> Calls In Progress.
>
> You can't send a 302 to a call thats already established.

Yes and I don't want to touch established calls - those calls can stay 
there until they drop. This is sent to new requests when 
switch_core_session_request fails in mod_sofia.

>> Turns out not all my endpoints support it :(
>
> AKA broken endpoints.  :)

Some are broken. Some just have this feature disabled. For 'security 
reasons'. You know the drill.


{P^/
John