504 Timeouts not changing after restarting the service

Help!
1

Morning
I have been playing with HAProxy for a few months now, I set up proof of concept which clearly showed how amazing it is, followed by a minor production deployment, to now a full blown HAProxy active /passive deployment on our intranet.

However end users have been experiencing the 504 timeout issue, here is an example from the log:
haproxy[1865]: x.x.x.x:50479 [03/Jul/2019:08:27:09.382] http_front http_back/server.server.com 0/0/1/-1/50002 504 195 - - sH-- 42/40/1/0/0 0/0 “POST /cgi-bin/lansaweb?wam=G_UVE&webrtn=display&ml=LANSA:XHTML&partHTTP/1.1”

In the HAProxy config I had set 50000ms as the timeout for both the client and the server - the reason for this is that some requests require a significant amount of time to compile from a backend db - our sites are spread across the country…

So I increased the timeouts:

timeout connect 500
timeout client 1200000
timeout server 1200000

However even after restarting HAProxy - the 504 apperas to be still set at 50000 as evidenced above.

any help / advice would be greatly appreciated.

Many thanks

2

You probably have an old haproxy process running with the old configuration. Because haproxy uses REUSEPORT, parallel binds to the same port are allowed and the linux kernel then load-balances between the old and the new instance, causing inconsistent behavior.

3

thank you for that - how can I check that is the case, and if so how do I kill it off - or is it just a case of rebooting the HAProxy?

4

Stop haproxy and then killall haproxy. This of course will completely interrupt any services.

Otherwise you need to check ps, netstat or ss output.