Fedora kernel-2.6.17-1.2142_FC4 patched with stable patch-2.6.17.4-vs2.0.2-rc26.diff

[linux-2.6.git] / Documentation / networking / ip-sysctl.txt

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index a2c893a..f12007b 100644 (file)
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -46,6 +46,29 @@ ipfrag_secret_interval - INTEGER
        for the hash secret) for IP fragments.
        Default: 600
 
        for the hash secret) for IP fragments.
        Default: 600
 

+ipfrag_max_dist - INTEGER
+       ipfrag_max_dist is a non-negative integer value which defines the 
+       maximum "disorder" which is allowed among fragments which share a 
+       common IP source address. Note that reordering of packets is 
+       not unusual, but if a large number of fragments arrive from a source 
+       IP address while a particular fragment queue remains incomplete, it 
+       probably indicates that one or more fragments belonging to that queue 
+       have been lost. When ipfrag_max_dist is positive, an additional check 
+       is done on fragments before they are added to a reassembly queue - if 
+       ipfrag_max_dist (or more) fragments have arrived from a particular IP 
+       address between additions to any IP fragment queue using that source 
+       address, it's presumed that one or more fragments in the queue are 
+       lost. The existing fragment queue will be dropped, and a new one 
+       started. An ipfrag_max_dist value of zero disables this check.
+
+       Using a very small value, e.g. 1 or 2, for ipfrag_max_dist can
+       result in unnecessarily dropping fragment queues when normal
+       reordering of packets occurs, which could lead to poor application 
+       performance. Using a very large value, e.g. 50000, increases the 
+       likelihood of incorrectly reassembling IP fragments that originate 
+       from different IP datagrams, which could result in data corruption.
+       Default: 64
+

 INET peer storage:
 
 inet_peer_threshold - INTEGER
 INET peer storage:
 
 inet_peer_threshold - INTEGER


@@ -78,6 +101,11 @@ inet_peer_gc_maxtime - INTEGER
 
 TCP variables: 
 
 
 TCP variables: 
 

+tcp_abc - INTEGER
+       Controls Appropriate Byte Count defined in RFC3465. If set to
+       0 then does congestion avoid once per ack. 1 is conservative
+       value, and 2 is more agressive.
+

 tcp_syn_retries - INTEGER
        Number of times initial SYNs for an active TCP connection attempt
        will be retransmitted. Should not be higher than 255. Default value
 tcp_syn_retries - INTEGER
        Number of times initial SYNs for an active TCP connection attempt
        will be retransmitted. Should not be higher than 255. Default value


@@ -304,63 +332,12 @@ tcp_low_latency - BOOLEAN
        changed would be a Beowulf compute cluster.
        Default: 0
 
        changed would be a Beowulf compute cluster.
        Default: 0
 

-tcp_westwood - BOOLEAN
-        Enable TCP Westwood+ congestion control algorithm.
-       TCP Westwood+ is a sender-side only modification of the TCP Reno 
-       protocol stack that optimizes the performance of TCP congestion 
-       control. It is based on end-to-end bandwidth estimation to set 
-       congestion window and slow start threshold after a congestion 
-       episode. Using this estimation, TCP Westwood+ adaptively sets a 
-       slow start threshold and a congestion window which takes into 
-       account the bandwidth used  at the time congestion is experienced. 
-       TCP Westwood+ significantly increases fairness wrt TCP Reno in 
-       wired networks and throughput over wireless links.   
-        Default: 0
-
-tcp_vegas_cong_avoid - BOOLEAN
-       Enable TCP Vegas congestion avoidance algorithm.
-       TCP Vegas is a sender-side only change to TCP that anticipates
-       the onset of congestion by estimating the bandwidth. TCP Vegas
-       adjusts the sending rate by modifying the congestion
-       window. TCP Vegas should provide less packet loss, but it is
-       not as aggressive as TCP Reno.
-       Default:0
-
-tcp_bic - BOOLEAN
-       Enable BIC TCP congestion control algorithm.
-       BIC-TCP is a sender-side only change that ensures a linear RTT
-       fairness under large windows while offering both scalability and
-       bounded TCP-friendliness. The protocol combines two schemes
-       called additive increase and binary search increase. When the
-       congestion window is large, additive increase with a large
-       increment ensures linear RTT fairness as well as good
-       scalability. Under small congestion windows, binary search
-       increase provides TCP friendliness.
-       Default: 0
-
-tcp_bic_low_window - INTEGER
-       Sets the threshold window (in packets) where BIC TCP starts to
-       adjust the congestion window. Below this threshold BIC TCP behaves
-       the same as the default TCP Reno. 
-       Default: 14
-
-tcp_bic_fast_convergence - BOOLEAN
-       Forces BIC TCP to more quickly respond to changes in congestion
-       window. Allows two flows sharing the same connection to converge
-       more rapidly.
-       Default: 1
-
-tcp_default_win_scale - INTEGER
-       Sets the minimum window scale TCP will negotiate for on all
-       conections.
-       Default: 7
-

 tcp_tso_win_divisor - INTEGER
        This allows control over what percentage of the congestion window
        can be consumed by a single TSO frame.
        The setting of this parameter is a choice between burstiness and
        building larger TSO frames.
 tcp_tso_win_divisor - INTEGER
        This allows control over what percentage of the congestion window
        can be consumed by a single TSO frame.
        The setting of this parameter is a choice between burstiness and
        building larger TSO frames.

-       Default: 8
+       Default: 3

 
 tcp_frto - BOOLEAN
        Enables F-RTO, an enhanced recovery algorithm for TCP retransmission
 
 tcp_frto - BOOLEAN
        Enables F-RTO, an enhanced recovery algorithm for TCP retransmission


@@ -368,11 +345,23 @@ tcp_frto - BOOLEAN
        where packet loss is typically due to random radio interference
        rather than intermediate router congestion.
 
        where packet loss is typically due to random radio interference
        rather than intermediate router congestion.
 

+tcp_congestion_control - STRING
+       Set the congestion control algorithm to be used for new
+       connections. The algorithm "reno" is always available, but
+       additional choices may be available based on kernel configuration.
+

 somaxconn - INTEGER
        Limit of socket listen() backlog, known in userspace as SOMAXCONN.
        Defaults to 128.  See also tcp_max_syn_backlog for additional tuning
        for TCP sockets.
 
 somaxconn - INTEGER
        Limit of socket listen() backlog, known in userspace as SOMAXCONN.
        Defaults to 128.  See also tcp_max_syn_backlog for additional tuning
        for TCP sockets.
 

+tcp_workaround_signed_windows - BOOLEAN
+       If set, assume no receipt of a window scaling option means the
+       remote TCP is broken and treats the window as a signed quantity.
+       If unset, assume the remote TCP is not broken even if we do
+       not receive a window scaling option from them.
+       Default: 0
+

 IP Variables:
 
 ip_local_port_range - 2 INTEGERS
 IP Variables:
 
 ip_local_port_range - 2 INTEGERS


@@ -401,10 +390,14 @@ ip_dynaddr - BOOLEAN
        Default: 0
 
 icmp_echo_ignore_all - BOOLEAN
        Default: 0
 
 icmp_echo_ignore_all - BOOLEAN

+       If set non-zero, then the kernel will ignore all ICMP ECHO
+       requests sent to it.
+       Default: 0
+

 icmp_echo_ignore_broadcasts - BOOLEAN
 icmp_echo_ignore_broadcasts - BOOLEAN

-       If either is set to true, then the kernel will ignore either all
-       ICMP ECHO requests sent to it or just those to broadcast/multicast
-       addresses, respectively.
+       If set non-zero, then the kernel will ignore all ICMP ECHO and
+       TIMESTAMP requests sent to it via broadcast/multicast.
+       Default: 1

 
 icmp_ratelimit - INTEGER
        Limit the maximal rates for sending ICMP packets whose type matches
 
 icmp_ratelimit - INTEGER
        Limit the maximal rates for sending ICMP packets whose type matches


@@ -441,6 +434,23 @@ icmp_ignore_bogus_error_responses - BOOLEAN
        will avoid log file clutter.
        Default: FALSE
 
        will avoid log file clutter.
        Default: FALSE
 

+icmp_errors_use_inbound_ifaddr - BOOLEAN
+
+       If zero, icmp error messages are sent with the primary address of
+       the exiting interface.
+ 
+       If non-zero, the message will be sent with the primary address of
+       the interface that received the packet that caused the icmp error.
+       This is the behaviour network many administrators will expect from
+       a router. And it can make debugging complicated network layouts
+       much easier. 
+
+       Note that if no primary address exists for the interface selected,
+       then the primary address of the first non-loopback interface that
+       has one will be used regarldess of this setting.
+
+       Default: 0
+

 igmp_max_memberships - INTEGER
        Change the maximum number of multicast groups we can subscribe to.
        Default: 20
 igmp_max_memberships - INTEGER
        Change the maximum number of multicast groups we can subscribe to.
        Default: 20


@@ -616,6 +626,11 @@ arp_ignore - INTEGER
        The max value from conf/{all,interface}/arp_ignore is used
        when ARP request is received on the {interface}
 
        The max value from conf/{all,interface}/arp_ignore is used
        when ARP request is received on the {interface}
 

+arp_accept - BOOLEAN
+       Define behavior when gratuitous arp replies are received:
+       0 - drop gratuitous arp frames
+       1 - accept gratuitous arp frames
+

 app_solicit - INTEGER
        The maximum number of probes to send to the user space ARP daemon
        via netlink before dropping back to multicast probes (see
 app_solicit - INTEGER
        The maximum number of probes to send to the user space ARP daemon
        via netlink before dropping back to multicast probes (see


@@ -714,6 +729,33 @@ accept_ra - BOOLEAN
        Functional default: enabled if local forwarding is disabled.
                            disabled if local forwarding is enabled.
 
        Functional default: enabled if local forwarding is disabled.
                            disabled if local forwarding is enabled.
 

+accept_ra_defrtr - BOOLEAN
+       Learn default router in Router Advertisement.
+
+       Functional default: enabled if accept_ra is enabled.
+                           disabled if accept_ra is disabled.
+
+accept_ra_pinfo - BOOLEAN
+       Learn Prefix Inforamtion in Router Advertisement.
+
+       Functional default: enabled if accept_ra is enabled.
+                           disabled if accept_ra is disabled.
+
+accept_ra_rt_info_max_plen - INTEGER
+       Maximum prefix length of Route Information in RA.
+
+       Route Information w/ prefix larger than or equal to this
+       variable shall be ignored.
+
+       Functional default: 0 if accept_ra_rtr_pref is enabled.
+                           -1 if accept_ra_rtr_pref is disabled.
+
+accept_ra_rtr_pref - BOOLEAN
+       Accept Router Preference in RA.
+
+       Functional default: enabled if accept_ra is enabled.
+                           disabled if accept_ra is disabled.
+

 accept_redirects - BOOLEAN
        Accept Redirects.
 
 accept_redirects - BOOLEAN
        Accept Redirects.
 


@@ -724,8 +766,8 @@ autoconf - BOOLEAN
        Autoconfigure addresses using Prefix Information in Router 
        Advertisements.
 
        Autoconfigure addresses using Prefix Information in Router 
        Advertisements.
 

-       Functional default: enabled if accept_ra is enabled.
-                           disabled if accept_ra is disabled.
+       Functional default: enabled if accept_ra_pinfo is enabled.
+                           disabled if accept_ra_pinfo is disabled.

 
 dad_transmits - INTEGER
        The amount of Duplicate Address Detection probes to send.
 
 dad_transmits - INTEGER
        The amount of Duplicate Address Detection probes to send.


@@ -768,6 +810,12 @@ mtu - INTEGER
        Default Maximum Transfer Unit
        Default: 1280 (IPv6 required minimum)
 
        Default Maximum Transfer Unit
        Default: 1280 (IPv6 required minimum)
 

+router_probe_interval - INTEGER
+       Minimum interval (in seconds) between Router Probing described
+       in RFC4191.
+
+       Default: 60
+

 router_solicitation_delay - INTEGER
        Number of seconds to wait after interface is brought up
        before sending Router Solicitations.
 router_solicitation_delay - INTEGER
        Number of seconds to wait after interface is brought up
        before sending Router Solicitations.