MINOR: doc: Add docs for agent-addr configuration variable
diff --git a/doc/configuration.txt b/doc/configuration.txt
index d9ef878..c2ede71 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -10708,6 +10708,14 @@
 
   Supported in default-server: Yes
 
+agent-addr <addr>
+  The "agent-addr" parameter sets address for agent check.
+
+  You can offload agent-check to another target, so you can make single place
+  managing status and weights of servers defined in haproxy in case you can't
+  make self-aware and self-managing services. You can specify both IP or
+  hostname, it will be resolved.
+
 agent-port <port>
   The "agent-port" parameter sets the TCP port used for agent checks.