ipv4: improve documentation of ip_no_pmtu_disc

Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 3c12d9a7ed00391d5c3f49ef80d7b1ae9abc40fe..8a984e994e61616a9dba0a4f425a5b4371b3ae99 100644 (file)
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -16,8 +16,12 @@ ip_default_ttl - INTEGER
        Default: 64 (as recommended by RFC1700)
 
 ip_no_pmtu_disc - BOOLEAN
-       Disable Path MTU Discovery.
-       default FALSE
+       Disable Path MTU Discovery. If enabled and a
+       fragmentation-required ICMP is received, the PMTU to this
+       destination will be set to min_pmtu (see below). You will need
+       to raise min_pmtu to the smallest interface MTU on your system
+       manually if you want to avoid locally generated fragments.
+       Default: FALSE
 
 min_pmtu - INTEGER
        default 552 - minimum discovered Path MTU