Add clamp-mss-to-pmtu option and description

1 files changed, 4 insertions, 1 deletions

diff --git a/docs/_include/interface-ip.txt b/docs/_include/interface-ip.txt
index 2c92c944..6045a7a8 100644
--- a/docs/_include/interface-ip.txt
+++ b/docs/_include/interface-ip.txt
@@ -1,5 +1,5 @@
 .. cfgcmd:: set interfaces {{ var0 }} <interface> {{ var2 }} {{ var3 }}
-  {{ var5 }} {{ var6 }} ip adjust-mss <mss>
+  {{ var5 }} {{ var6 }} ip adjust-mss <mss | clamp-mss-to-pmtu>
 
   As Internet wide PMTU discovery rarely works, we sometimes need to clamp our
   TCP MSS value to a specific value. This is a field in the TCP options part of
@@ -12,6 +12,9 @@
   .. hint:: MSS value = MTU - 20 (IP header) - 20 (TCP header), resulting in
     1452 bytes on a 1492 byte MTU.
 
+  Instead of a numberical MSS value `clamp-mss-to-pmtu` can be used to 
+  automatically set the proper value.
+
 .. cfgcmd:: set interfaces {{ var0 }} <interface> {{ var2 }} {{ var3 }}
   {{ var5 }} {{ var6 }} ip arp-cache-timeout