Re: Algorithms and Hashing

Patrick Viet a écrit :
> On Wed, Mar 12, 2008 at 8:10 PM, Michael Rennt <m.rennt#gmx.net> wrote:
>
>
>> I see that the server identifier is stored inside the cookies. This is pretty
>> good, as it keeps stickyness even when there's a failover to another equally
>> configured loadbalancer.
>>
>
>
>> The only question left for now: How is all the hashing and distribution implemented?
>>
>> I see that the source IP (or whatever other parameter) is hashed and divided by
>> the total weight of all servers. But what if a new server is added?
>> Won't the stickiness be completely different after that, messing up any existing
>> stickiness?
>>
>
> The hashing choice is done only if there isn't already a persistency cookie.
> Therefore the old sessions don't move, and the new sessions will
> benefit from the extra server.
> You should really try the software. Nothing beats experience.
>
> Patrick
>
>

I was asking this because we are using tcp mode which don't use cookie for persistency so the only thing that is important, I think, is to define the backend server in the same order on my 2 haproxy. That way a particular client with is hash will always end up on them same backend server.

I will do more testing but in tcp mode the important thing in a ha setup is to define alle the server in the same order.

I'M correct here ?

Thanks

-- 
Guillaume Bourque, B.Sc.,
consultant, infrastructures technologiques
Logisoft Technologies inc.
514 576-7638
http://www.logisoftech.com