assuming debian11 (rsyslog to sysklogd)
note /dev/log is reachable even when chroot is enabled
ls -lF /var/lib/haproxy/dev/log
this is thanks to the rsyslog AddUnixListenSocket setting
cat /etc/rsyslog.d/49-haproxy.conf
the default setup prints to /var/log/haproxy.log by default
so with rsyslog on debian11, everything is fine already – however if you want GNU syslogd or sysklogd, you need to send logs through UDP
vi /etc/syslog.conf
local0.* -/var/log/haproxy.log
cd /etc/haproxy/ vi haproxy.cfg
we need the logs to be sent to local syslog daemon
log 127.0.0.1 local0
systemctl status rsyslog
systemctl status haproxy
tail -F /var/log/haproxy.log
https://www.haproxy.com/blog/introduction-to-haproxy-logging
https://www.haproxy.com/documentation/haproxy-configuration-manual/latest/#8
https://www.haproxy.com/documentation/haproxy-configuration-manual/latest/#4-log-format
https://www.haproxy.com/documentation/haproxy-configuration-manual/latest/#4-log-format-sd
https://www.haproxy.com/documentation/haproxy-configuration-manual/latest/#4-log-tag
https://serverfault.com/questions/937035/what-is-the-meaning-of-these-haproxy-configuration-lines
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/load_balancer_administration/s1-haproxy-logging#doc-wrapper ==> rsyslog & path to chroot /dev/log
https://www.haproxy.com/blog/haproxy-log-customization
https://ahmadallish.substack.com/p/json-logging-in-haproxy-the-right-way-3636297d2d49
FW https://medium.com/thirddev/json-logging-in-haproxy-the-right-way-3636297d2d49