The haproxy is currently a container that hops around on random servers.

• Marc, 17.10.21 01:15

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I have been trying to get a simple health check in haproxy to work. But somehome the haproxy request is differently handled then a curl request, which generates a socket error in haproxy. [...]

For stats, you can use "socat" to talk to haproxy's stat socket instead of using its HTTP interface. For example, with "stats socket /var/lib/haproxy/stats" in haproxy's config, you can then do:

echo "show stat" | socat - "UNIX-CONNECT:/var/lib/haproxy/stats"

Maybe there is a way to also expose your health check status on a local socket instead of an HTTP listener? This would at least eliminate having to deal with missing or superfluous CR/LFs, spaces, etc.

Just a thought.

HTH, Thomas

Not sure where to report this as bug. Does it work if you change the script to look like:

printf 'HTTP/1.1 200 OK\r\nContent-Length: 0\r\n\r\n' exit 0

Aki

On 19/10/2021 23:29 Marc marc@f1-outsourcing.eu wrote:

Should this be filed as a bug somewhere?

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I have been trying to get a simple health check in haproxy to work. But somehome the haproxy request is differently handled then a curl request, which generates a socket error in haproxy.

The health script echos these lines, with this config[2]

echo -ne "HTTP/1.1 200 OK\r\n"
echo -ne "Content-Length: 0\r\n"
echo -ne "\r\n"
exit 0

The curl request generates ok, haproxy generates socket error. The haproxy=yes, reuseport=yes do not seem to resolve anything. If stop dovecot and run "dovecot-health-check.sh | nc -l 192.168.10.46 5001" then the haproxy check is ok. So I guess the script is ok. But what is dovecot then doing with it's output when haproxy is requesting it?

[1] https://discourse.haproxy.org/t/httpck-on-bash-script-results-in-socket- error/5647/16

[2] service health-check { executable = script -p /usr/local/sbin/dovecot-health-check.sh inet_listener health-check { port = 5001 haproxy = no reuse_port = no } }

I noticed that your script didn't work for me, for some reason I got

-ne HTTP/1.1 200 OK

-ne Content-Length: 0

-ne

which of course does not make sense... can you try if this works? I'm guessing your script probably looks pretty much like this already...

#!/bin/bash timeout=10 trap "exit 0" QUIT { sleep $timeout kill -3 $$ 2>/dev/null } & read -r input exit_code=$? if [ ${exit_code} -eq 0 ]; then echo -n -e "HTTP/1.1 200 OK\r\n" echo -n -e "Content-Length: 0\r\n" echo -n -e "\r\n" fi exit 0

On 20/10/2021 11:55 Marc marc@f1-outsourcing.eu wrote:

No, if I stop the dovecot service. I am getting from haproxy the 'L4CON in 0ms' and when I start dovecot with the new printf in the bash script, the same error 'SOCKERR in 8ms'(not tried with the options haproxy, reuseport)

I am not sure what this haproxy=yes should do, but tcpdumps show that transmissions between curl requests and haproxy requests are handled differently. The people of haproxy say they use an OPTIONS request. I used this also with curl -X OPTIONS, but still the curl is returning ok, while haproxy keeps complaining.

...

Not sure where to report this as bug. Does it work if you change the script to look like:

printf 'HTTP/1.1 200 OK\r\nContent-Length: 0\r\n\r\n' exit 0

...

Should this be filed as a bug somewhere?

...

I have been trying to get a simple health check in haproxy to work.

But

...

...

somehome the haproxy request is differently handled then a curl request, which generates a socket error in haproxy.

The health script echos these lines, with this config[2]

echo -ne "HTTP/1.1 200 OK\r\n"
echo -ne "Content-Length: 0\r\n"
echo -ne "\r\n"
exit 0

The curl request generates ok, haproxy generates socket error. The haproxy=yes, reuseport=yes do not seem to resolve anything. If stop dovecot and run "dovecot-health-check.sh | nc -l 192.168.10.46 5001" then the haproxy check is ok. So I guess the script is ok. But what is dovecot then doing with it's output when haproxy is requesting it?

[1] https://discourse.haproxy.org/t/httpck-on-bash-script-results-in- socket- error/5647/16

[2] service health-check { executable = script -p /usr/local/sbin/dovecot-health-check.sh inet_listener health-check { port = 5001 haproxy = no reuse_port = no } }