diff --git a/postfix/main.cf b/postfix/main.cf
index 261a71ce..0ead2587 100644
--- a/postfix/main.cf
+++ b/postfix/main.cf
@@ -11,7 +11,7 @@ alias_maps = hash:/etc/aliases
 alias_database = hash:/etc/aliases
 mydestination = localhost.localdomain, localhost
 relayhost = 
-mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
+mynetworks = 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128 172.17.42.1/16
 mailbox_size_limit = 0
 recipient_delimiter = +
 inet_interfaces = all