Hi On 03.06.2013 23:36, Ali Majdzadeh wrote: > Hello All, > I am totally new to HAProxy. What I am looking for is a solution for > HTTP load balancing and according to what I have read about HAProxy, I > think this is the right choice. There are a lot of cases where haproxy is fine. > Concerning HTTP, HAProxy is session-aware. HAProxy supports different methods for persistence, e.g. Cookie insertion.
> Does this mean that all the requests initiated from a specific client > goes only to a specific back-end server? That is what persistence should do. > What happens if suddenly the back-end server fails? For example, > suppose that a user is downloading a file from a back-end web server > and the same file exists on another back-end web server. I think it will cause the download to be aborted, but Iam not 100% sure. You can tell haproxy to break persistence in the case of a failure. > The load on these two servers is balanced by HAProxy. Now, what > happens if the first web server dies whilst the file is being > downloaded? Does the download continues from the second server from > where it was interrupted? I am not sure whether I have got the correct > understanding of session-awareness feature in HAProxy. I do appreciate > your comments. session awareness needs to be done at application level, e.g. you could have a central memcache or datebase that stores your session data. In case of a failure, the next request could go to another server, which explicitly breaks persistence. But because you have a central session store that doesnt matter. Please have a look at http://code.google.com/p/haproxy-docs/wiki/redispatch As I sad earlier, If you have a download and the server dies, this will cause the download to be aborted. And this has nothing to do with session awareness. > Thanks in advance. > > *Ali Majdzadeh Kohbanani* > *Managing Director* > *Abshar Data Processing* > > *Tel:+982144160700 > * > *Tel/Fax: +982144160701 > * > *Cell:+989123614728* > *[email protected] <mailto:[email protected]> > * > *http://www.abshar.biz* > cheers, thomas
