Jonathan, Lukas Thanks for your valuable comments. Would you please indicate some of those moving parts that could fail during a single download, Jonathan? From Lukas comments, I realized that at least some parts of the problem are related to the client agent, is that right? I mean, for example, being the primary server failed, if the client agent retries the download request, HAProxy can proxy the new request to the other back-end server and download continues from where it was interrupted, is this conclusion correct? Thanks again.\
Warm Regards, Ali *Ali Majdzadeh Kohbanani* *Managing Director* *Abshar Data Processing* *Tel:+982144160700 * * Tel/Fax: +982144160701 * *Cell:+989123614728* *[email protected] * *http://www.abshar.biz* 2013/6/4 Lukas Tribus <[email protected]> > Hi Ali, > > > Now, what happens if the first web server dies whilst the file is being > > downloaded? > > The download is interrupted. If the client uses a smart user-agent, like > a recent browser, a download manager or wget, then it will reconnect and > download from the other backend server. > > What HAProxy can do is to fail-over from on server to the other at the > next transaction. > > There is no way for HAProxy to hide a backend server failure once the > transaction is in-flight (past the HTTP header; forwarding the payload). > > > You will have to ensure that both the proxy, the backend and all > intermediate devices like switches and routers are as stable as possible > (dual PSU on different protected power feeds, ECC RAM, RAID HD, stable > kernel/applications, etc...). > > > Regards, > Lukas
