On wo, 2014-09-10 at 11:47 +0200, Pavlos Parissis wrote: > On 10/09/2014 07:02 πμ, Juho Mäkinen wrote: > > Thanks Pavlos for your help. Fortunately (and embarrassedly for me) the > > mistake was not anywhere near haproxy but instead my haproxy configure > > template system had a bug which mixed up the backend name and ip > > address. Because of this haproxy showed different names for those > > servers which were actually down and that threw me into way off when I > > investigated this issue, blinded by the actual problem which was always > > so near of my sight. :( > > > > This is one of the reason I use hostname rather IPs. I know people say > that DNS lookup has some cost but in my environment with ~300 pools and > ~2K servers, we didn't notice any major problem. But, I have to say that > I never looked at possible slow downs due to DNS lookups. > > Other Load balancers, F5 for instance, are strongly suggest to use IPs. >
I don't think you need to worry about DNS lookups with haproxy. As I understand it, all lookups are done while starting haproxy, after that it will just use the IP address directly. > > > haproxy shows the server name in the server log when it reports health > > check statuses. Example: > > "Health check for server comet/comet-172.16.4.209:3500 succeeded, > > reason: Layer7 check passed, code: 200, info: "OK", check duration: 2ms, > > status: 3/3 UP." > > > > This could be improved by also showing the actual ip and port in the > > log. Suggestion: > > "Health check for server comet/comet-172.16.4.209:3500 > > (172.16.4.209:3500 <http://172.16.4.209:3500>) succeeded, reason: Layer7 > > check passed, code: 200, info: "OK", check duration: 2ms, status: 3/3 UP." > > > > I don't know C, but I think it should be relative easy to implement. > > > > As a side question: The documentation was a bit unclear. If I have > > > nbproc > 1 and I use the admin socket to turn servers administrative > > > status down or up, do I need to do it to separated admin sockets per > > > haproxy process, or can I just use one admin socket? > > > > > > > You need a different socket. Each process can only be managed by a > > dedicated stats socket. There isn't any kind of aggregation where you > > issue a command to 1 stats socket and this command is pushed to all > > processes. Next release will address this kind of issues. > > > > > > Thank you, good to know! > > > > - Garo > > > >
