diff --git a/doc/html/man5/3proxy.cfg.5.html b/doc/html/man5/3proxy.cfg.5.html
index 0af8364..d91f020 100644
--- a/doc/html/man5/3proxy.cfg.5.html
+++ b/doc/html/man5/3proxy.cfg.5.html
@@ -825,6 +825,26 @@ the external address for this request to <ip>.
It can be chained with another parent type. It’s
useful to set the external IP based on ACL or make it
random.
+extport does not redirect the request; it sets the range
+the local port of outgoing connections is taken from, given
+as FIRST-LAST inclusive in place of the port
+argument, with 0.0.0.0 as the address, for example parent
+1000 extport 0.0.0.0 40000-40100. Where the system can
+be asked to pick the port itself (Linux
+IP_LOCAL_PORT_RANGE) it does, otherwise a port is
+picked at random from the range and retried if it is already
+in use, up to ten times. It can be chained with another
+parent type, and the access rule it belongs to decides which
+requests it applies to, so allow * * * * UDPASSOC
+followed by parent 1000 extport 0.0.0.0 40000-40100
+limits it to UDP associations. The range is applied when the
+outgoing connection is made, so a kept alive connection
+carrying several requests uses the rule that matched when it
+was opened.
+intport is the same for sockets bound on the side facing
+the client: the port a UDP association tells the client to
+send its datagrams to, and the FTP proxy data connection.
+
tcp simply redirect connection. TCP is always last in
chain. This type of proxy is a simple TCP redirection, it
does not support parent authentication.