1 files changed, 12 insertions, 1 deletions

diff --git a/man5/opentracker.conf.5 b/man5/opentracker.conf.5
index 67e624f..9a836ae 100644
--- a/man5/opentracker.conf.5
+++ b/man5/opentracker.conf.5
@@ -79,7 +79,18 @@ Specifies the path to the stats location. You can configure opentracker to appea
 Specifies the IP address or network of the reverse proxies. Opentracker will take the X-Forwarded-For address instead of the source IP address. Can be added more than once.
 .Pp
 .It livesync.cluster.listen Ar ip_address:port
-Specifies the IP address and port opentracker will listen on for incoming live sync packets to keep a cluster of opentrackers synchronized.
+Specifies the IP address and port opentracker will listen on for incoming live
+sync packets to keep a cluster of opentrackers synchronized. Every member of a
+cluster has to agree on the port, which is also the one packets are sent to.
+.Pp
+.It livesync.cluster.group Ar ip_address
+Specifies the multicast group a cluster talks in. For reaosns of backwards
+comaptibility with legacy trackers, it defaults to 224.0.23.5, which,
+technically sits in a range IANA assigns on request.
+
+A cluster of its own is better served by an address out of 239.192.0.0/14,
+which RFC 2365 sets aside for private use. Packets carry a ttl of 1 either
+way and never leave the local link.
 .Pp
 .It livesync.cluster.node_ip Ar ip_address
 Specifies one trusted IP address for sync between trackers running in a cluster. Can be added more than once.