failover / fault-tolerant configurations

[alex clemesha]

On Wed, May 21, 2008 at 1:25 PM, J Davis <mrsalty0 at gmail.com> wrote:
> If you have multiple machines running identically configured instances of
> nginx, then you can configure the IP failover using something like wackamole
> or heartbeat.
> You won't need anything special for the nginx configuration.
Ok, thanks.  I've glanced at both wackamole and heartbeat before, but
I will now give them a closer look.


> Session affinity can be enable in nginx using ip_hash directive of the nginx
> upstream module.
> One thing this will not get you is session failover. In other words, if your
> active instance of nginx dies the current information about session affinity
> will also be lost.
I had a feeling this might be the case.  Are there any
specific ways one can minimize / eliminate the loss of the
current session information, or is this not possible with Nginx?

Thanks Jake,

-Alex


>
> http://wiki.codemongers.com/NginxHttpUpstreamModule#ip_hash
> http://www.backhand.org/wackamole/
> http://www.linux-ha.org/
>
> -Jake
>
> On Wed, May 21, 2008 at 3:22 PM, alex clemesha <clemesha at gmail.com> wrote:
>>
>> Hi,
>>
>> I'm looking for more information on setting up 2 Nginx instances
>> in a failover active/active configuration.
>>
>> The scenario that I'm trying to accomplish is this:
>>
>> 2 Nginx instances, both doing some sort of Session affinity
>> with, say the
>> http://wiki.codemongers.com/NginxHttpUpstreamRequestHashModule
>> module.
>>
>> If one of the Nginx instance fails, I hope to have the second keep
>> handling incoming requests.
>>
>> ---
>>
>> Now, I'm not sure if I'm verbalizing what I'm trying to do correctly,
>> but my general goal is to create a fault - tolerant setup.
>>
>> Any advice is appreciated, especially any advice of best practices
>> in this general arena, Nginx limitations, or alternate configurations.
>>
>>
>> thanks,
>> Alex
>>
>
>