[SAC] errors with Trac

[Paul Spencer]

On 2009-10-02, at 3:20 AM, Christopher Schmidt wrote:

> On Thu, Oct 01, 2009 at 05:33:10PM -0400, Paul Spencer wrote:
>> We replaced our router with a fancy new dual-wan VPN router and it  
>> was
>> configured to load balance outgoing traffic between a DSL and a cable
>> connection (each having a different external IP address, one static  
>> and
>> one dynamic).  I thought this happened some time before we started
>> experiencing this problem and had forgotten about it.
>>
>> The solution appears to be to direct all outgoing traffic to the  
>> osgeo
>> servers trac, www and svn to use only one of the connections.  It is
>> still unclear what is different between OSGeo's setup and the setup  
>> on
>> openlayers.org and our own trac/svn but I suspect that somehow the
>> authentication is being done with some affinity to the user's IP  
>> address,
>> which in our case was changing essentially randomly between  
>> subsequent
>> requests.  I have not confirmed this
>
> I'm surprised that your own trac and the OL trac weren't equally  
> affected; in
> my experience, I've always had trac get cranky when I switch  
> connections, but
> since I only do it a coule times a day, that's obviously not  
> particularly
> scientific.
>
> Trac version may also play a role; if your trac is newer, the behavior
> may have changed.
>

we just upgraded to 0.11.5 a couple of days ago, but before that we  
were on the same version as OSGeo so I think trac version is not a  
factor.

I am convinced the problem is with our router, I think it should be  
maintaining some sort of session affinity for users connecting to  
specific IPs within a given timeframe by routing them out the same WAN  
connection.  For whatever reason, I think this is working for some  
destinations but not for others.

In any case, I apologize for the extra noise this created but  
hopefully if someone else starts reporting a similar issue this may be  
the cause/resolution for them as well :)

Cheers

Paul

__________________________________________

    Paul Spencer
    Chief Technology Officer
    DM Solutions Group Inc
    http://research.dmsolutions.ca/