> Using HA-Proxy version 1.5.6 2014/10/18 on CentOS 6, recently updated, etc.
Upgrade anyway, you may be hitting a bug thats already fixed:
~/haproxy-1.5$ git log --oneline v1.5.6.. | grep agent
bfb8f88 BUG/MEDIUM: Do not consider an agent check as failed on L7 error
8eccbf7 MEDIUM/BUG: Only explicitly report "DOWN (agent)" if the agent health
is zero
5ed62d6 BUG/MEDIUM: Do not set agent health to zero if server is disabled in
config
1f96a87 BUG/MEDIUM: checks: fix conflicts between agent checks and ssl
healthchecks
~/haproxy-1.5$
Regards,
Lukas