Re: Balancing bytes in/out
On Sat, Aug 15, 2009 at 10:32:40AM +0800, Nelson Serafica wrote: > Its only http and https. The site is not a forum but a site with a lots of > transaction such as accounting, etc. > > When I tried to use leastconn, it affects some transaction such as > authentication. backend says he was successfully disconnected while the web > interface says he was still logon so I revert to round-robin and everything > back to normal except not balance bytes or traffic. The load-balancing algorithm cannot have such an impact on the functional behaviour of the site. Either all algos fail (with varying failure rates) or all work. Your description makes me think that your site may require persistence, and that using a different algo most often hides a pending issue. You'd better double check before you're hit by a bigger problem ! Regards, Willy
Re: Balancing bytes in/out
Its only http and https. The site is not a forum but a site with a lots of transaction such as accounting, etc. When I tried to use leastconn, it affects some transaction such as authentication. backend says he was successfully disconnected while the web interface says he was still logon so I revert to round-robin and everything back to normal except not balance bytes or traffic. It will depend on the type of traffic and application in fact. A site such as a forum or similar where people never go away can indeed stick users for a long time to a server. But after all, that's the precise reason you're using cookies in the first place.
Re: Balancing bytes in/out
On Thu, Aug 13, 2009 at 05:21:28AM -0400, John Lauro wrote: > The biggest issue probably is that you are using cookies that will tie a > client to a server. For me, I noticed it often takes over 3 days to get the > first 80% of the traffic off if I mark a server as soft down as people never > reboot or close the browser. If you have more random traffic and less > regular visitors it might not take so long. It will depend on the type of traffic and application in fact. A site such as a forum or similar where people never go away can indeed stick users for a long time to a server. But after all, that's the precise reason you're using cookies in the first place. A site where people consult some information (eg: online sales) will not have this behaviour because people don't stay that long. > Leastconn is more accurate for how the servers look at that moment in time. Leastconn is only accurate for long sessions. In fact, it's still accurate enough for short sessions because it does roundrobin between servers at an equal number of sessions, but it should really be avoided for short sessions such as HTTP. It's fine for SQL, LDAP, TSE, ... though. > However, it does not take into account all clients that closed the session > but have a cookie for a server, and it's only used for clients that don't > already have a cookie. Round robin or one of the other methods might work > better, but it can take close to a week for you to know if it's any better > or not as a large number of your users are already tied to a specific server > with a cookie. I used to use roundrobin and I think it worked better with > cookies, but currently I don't have any traffic requiring cookies and so > leastconnn has been working better. Anyway, given the differences between the two counters, I don't even think the LB algo is the cause. We don't have the other columns, but I'd suspect that one of the servers is regularly offline due to failed health-checks while the other one is not. Regards, Willy
Re: Balancing bytes in/out
FYI, I think the default unit for times in haproxy is ms not seconds, so these are not correct, AFAIK. clitimeout 6 # 16.6 Hrs. 60 seconds srvtimeout 3 # 8.33 Hrs. 30 seconds contimeout 4000 # 1.11 Hrs. 4 seconds On 8/12/09 10:22 PM, Nelson Serafica wrote: clitimeout 6 # 16.6 Hrs. srvtimeout 3 # 8.33 Hrs. contimeout 4000 # 1.11 Hrs.
RE: Balancing bytes in/out
> Is there something I need to change in my config. I set it as leastconn > to balance traffic but it isn't. Can haproxy knows to transfer request > to other back end when it knows it has a much more traffic compare to > other server? > It can not transfer to a different server when you tie the client down to a server with a cookie. If you can narrow down which traffic has to be tied down to a specific server, I think you could ignore the cookie for the other traffic and have better balance.
RE: Balancing bytes in/out
The biggest issue probably is that you are using cookies that will tie a client to a server. For me, I noticed it often takes over 3 days to get the first 80% of the traffic off if I mark a server as soft down as people never reboot or close the browser. If you have more random traffic and less regular visitors it might not take so long. Leastconn is more accurate for how the servers look at that moment in time. However, it does not take into account all clients that closed the session but have a cookie for a server, and it's only used for clients that don't already have a cookie. Round robin or one of the other methods might work better, but it can take close to a week for you to know if it's any better or not as a large number of your users are already tied to a specific server with a cookie. I used to use roundrobin and I think it worked better with cookies, but currently I don't have any traffic requiring cookies and so leastconnn has been working better. > -Original Message- > From: Nelson Serafica [mailto:ntseraf...@gmail.com] > Sent: Thursday, August 13, 2009 1:23 AM > To: HAproxy Mailing Lists > Subject: Balancing bytes in/out > > I just install and run haproxy for almost 3 months now and found no > problem with it. Its just that I just notice that in my MRTG, the > traffic is not the same. HAPROXY has SERVER A and SERVER B as backend > web server. In the mrtg, SERVER B has a lot traffic compare to SERVER > A. I have enable stats and I notice that Bytes IN/OUT is not almost > equal (see attachment). Here is the config of my haproxy: > > listen WEB_SERVERS 1.2.3.4:80 > mode http > clitimeout 6 # 16.6 Hrs. > srvtimeout 3 # 8.33 Hrs. > contimeout 4000 # 1.11 Hrs. > balance leastconn > option forwardfor > option httpclose > cookie igx insert nocache indirect > server WEBA 2.3.4.5:80 cookie igx1 maxconn 2500 inter 1000 > fastinter 200 fall 2 check > server WEBB 2.3.4.6:80 cookie igx2 maxconn 2500 inter 1000 > fastinter 200 fall 2 check > stats uri /my_stats > stats realm Global\ statistics > stats auth stats:password > global > maxconn 1 # Total Max Connections. > log 127.0.0.1 local0 > log 127.0.0.1 local1 notice > daemon > nbproc 1 # Number of processes > userhaproxy > group haproxy > chroot /var/chroot/haproxy > defaults > log global > option httplog > modetcp > clitimeout 6 # 16.6 Hrs. > srvtimeout 3 # 8.33 Hrs. > contimeout 4000 # 1.11 Hrs. > retries 3 > option redispatch > option httpclose > > Is there something I need to change in my config. I set it as leastconn > to balance traffic but it isn't. Can haproxy knows to transfer request > to other back end when it knows it has a much more traffic compare to > other server? > > > No virus found in this incoming message. > Checked by AVG - www.avg.com > Version: 8.5.392 / Virus Database: 270.13.47/2289 - Release Date: > 08/12/09 18:12:00
