using parallel varnishes

[Martin Boer]

Per Buer wrote:
> On Fri, Jun 18, 2010 at 7:02 AM, Don Faulkner <dfaulkner at pobox.com> wrote:
>   
>> I like the setup. But for some reason I think it needs to be:
>>
>> web server -> load balancer -> cache -> load balancer -> ssl endpoint
>>     
>
>
> One thing to consider; almost any server that is still within warranty
> can deliver at least 1Gbps of traffic through Varnish, on new hardware
> reaching 10Gbps shouldn't be that big a deal (is there someone out
> there with 10Gbps hardware that would like to help us test? :-). So,
> you should ask yourself - do you really need a load balancer in front
> of Varnish? Having more Varnish server than you need will decrease
> your hit rate (unless you're hashing on the URL) and will increase
> your response time. It will also add to the complexity of the setup.
> Relying on a simple cluster of just two servere where just the IP
> address moves in case of failure will in a lot of scenarios lead to
> better performance and better uptime.
>
>   
The reason we want the double loadbalancer setup is that with 2 active 
varnishes one can fail without having 90+ % increase of hits to the 
backend servers for as long as it takes to get the backup-varnish loaded 
up.

We don't have a lot of traffic but during peakhours having a slow 
website will scare away potential paying customers instantly.
The setup we plan is simple enough protocol/application wise.
The complexity is in the number of SSL entrances we need for all of our 
brands, not in the network setup.
I can understand what it should do which automatically means it's quite 
simple. :)

Regards,
Martin