AW: AW: proxy failover/load balance

[Plüm, Rüdiger, VIS <ru...@vodafone.com>]

-----Ursprüngliche Nachricht-----
Von: Robby Pedrica 

> Hi Rudiger,
>
> I've applied patches and recompiled. My results are as follows:
> 
> 1. apache starts up with the member 'b' disabled now
> 2. if I shutdown the working member 'a' httpd, then manager shows the change only when you try and access the web site. Moves from state ok to err
> 3. If I bring the member 'a' back up again ( start httpd ) then manager shows the move from err to ok only after trying to access the site.

2. and 3. work as designed. httpd only changes the status for a worker to err if a request failed in the middle or if it tried to assign a request
to this worker and that failed. Once the worker is in error state httpd will not try to assign a new request to this worker for "retry" seconds
(see parameter explanation at http://httpd.apache.org/docs/2.2/mod/mod_proxy.html#proxypass). After that grace period the worker gets new requests
assigned again and will switch back to ok once it processed the assigned request successfully.

> 
> This is definitely an improvement even if failover isn't working because at least we can manually failover ...

Considering my explanation above, what do you mean by "failover isn't working"?

Regards

Rüdiger

Re: AW: AW: proxy failover/load balance

[Jim Jagielski <ji...@jaguNET.com>]

I think we're in agreement that the current "failover" does
not work as it should with HTTP, and is quite
cumbersome to get it to work. :)

I hope to later on this week work on code that has
a real "hot standby" status, and avoids the requirement
for sticky sessions. It won't replace what's in
there now (for AJP) but will make it easier
to implement failover for simple tasks.