I have used the above directive in my configuration file under defaults. And it has made not even the slightest difference in seeing messages like the following getting printed from our http client:
HTTP/1.0 408 Request Time-outCache-Control: no-cacheConnection: closeContent-Type: text/html <html><body><h1>408 Request Time-out</h1>Your browser didn't send a complete request in time.</body></html> I am running HaProxy 1.5.8 Here are my defaults: defaults log global mode http balance leastconn option httplog retries 1 option redispatch option log-health-checks timeout client 1m timeout connect 30s timeout server 1m timeout check 10000 # suppress the html response in 408 timeout errors errorfile 408 /dev/null