X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=Documentation%2Fnetworking%2Fip-sysctl.txt;h=c97932c88ea3a39b8547d67df667061c9b677a30;hb=8ed1dc44d3e9e8387a104b1ae8f92e9a3fbf1b1e;hp=8a984e994e61616a9dba0a4f425a5b4371b3ae99;hpb=a6ddeee32dadec066e910c7dcd237be732535fc2;p=~andy%2Flinux

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index 8a984e994e6..c97932c88ea 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -15,17 +15,47 @@ ip_default_ttl - INTEGER
 	forwarded) IP packets. Should be between 1 and 255 inclusive.
 	Default: 64 (as recommended by RFC1700)
 
-ip_no_pmtu_disc - BOOLEAN
-	Disable Path MTU Discovery. If enabled and a
+ip_no_pmtu_disc - INTEGER
+	Disable Path MTU Discovery. If enabled in mode 1 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.
+
+	In mode 2 incoming Path MTU Discovery messages will be
+	discarded. Outgoing frames are handled the same as in mode 1,
+	implicitly setting IP_PMTUDISC_DONT on every created socket.
+
+	Mode 3 is a hardend pmtu discover mode. The kernel will only
+	accept fragmentation-needed errors if the underlying protocol
+	can verify them besides a plain socket lookup. Current
+	protocols for which pmtu events will be honored are TCP, SCTP
+	and DCCP as they verify e.g. the sequence number or the
+	association. This mode should not be enabled globally but is
+	only intended to secure e.g. name servers in namespaces where
+	TCP path mtu must still work but path MTU information of other
+	protocols should be discarded. If enabled globally this mode
+	could break other protocols.
+
+	Possible values: 0-3
 	Default: FALSE
 
 min_pmtu - INTEGER
 	default 552 - minimum discovered Path MTU
 
+ip_forward_use_pmtu - BOOLEAN
+	By default we don't trust protocol path MTUs while forwarding
+	because they could be easily forged and can lead to unwanted
+	fragmentation by the router.
+	You only need to enable this if you have user-space software
+	which tries to discover path mtus by itself and depends on the
+	kernel honoring this information. This is normally not the
+	case.
+	Default: 0 (disabled)
+	Possible values:
+	0 - disabled
+	1 - enabled
+
 route/max_size - INTEGER
 	Maximum number of routes allowed in the kernel.  Increase
 	this when using large numbers of interfaces and/or routes.
@@ -160,6 +190,16 @@ tcp_app_win - INTEGER
 	buffer. Value 0 is special, it means that nothing is reserved.
 	Default: 31
 
+tcp_autocorking - BOOLEAN
+	Enable TCP auto corking :
+	When applications do consecutive small write()/sendmsg() system calls,
+	we try to coalesce these small writes as much as possible, to lower
+	total amount of sent packets. This is done if at least one prior
+	packet for the flow is waiting in Qdisc queues or device transmit
+	queue. Applications can still use TCP_CORK for optimal behavior
+	when they know how/when to uncork their sockets.
+	Default : 1
+
 tcp_available_congestion_control - STRING
 	Shows the available congestion control choices that are registered.
 	More congestion control algorithms may be available as modules,
@@ -1078,6 +1118,13 @@ bindv6only - BOOLEAN
 
 	Default: FALSE (as specified in RFC3493)
 
+anycast_src_echo_reply - BOOLEAN
+	Controls the use of anycast addresses as source addresses for ICMPv6
+	echo reply
+	TRUE:  enabled
+	FALSE: disabled
+	Default: FALSE
+
 IPv6 Fragmentation:
 
 ip6frag_high_thresh - INTEGER