Minimum time-to-live of entries. Should be enough to cover fragment
time-to-live on the reassembling side. This minimum time-to-live is
guaranteed if the pool size is less than inet_peer_threshold.
- Measured in jiffies(1).
+ Measured in seconds.
inet_peer_maxttl - INTEGER
Maximum time-to-live of entries. Unused entries will expire after
this period of time if there is no memory pressure on the pool (i.e.
when the number of entries in the pool is very small).
- Measured in jiffies(1).
+ Measured in seconds.
inet_peer_gc_mintime - INTEGER
Minimum interval between garbage collection passes. This interval is
in effect under high memory pressure on the pool.
- Measured in jiffies(1).
+ Measured in seconds.
inet_peer_gc_maxtime - INTEGER
Minimum interval between garbage collection passes. This interval is
in effect under low (or absent) memory pressure on the pool.
- Measured in jiffies(1).
+ Measured in seconds.
TCP variables:
+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_abc - INTEGER
Controls Appropriate Byte Count (ABC) defined in RFC3465.
ABC is a way of increasing congestion window (cwnd) more slowly
of two segments to compensate for delayed acknowledgments.
Default: 0 (off)
-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
- is 5, which corresponds to ~180seconds.
+tcp_abort_on_overflow - BOOLEAN
+ If listening service is too slow to accept new connections,
+ reset them. Default state is FALSE. It means that if overflow
+ occurred due to a burst, connection will recover. Enable this
+ option _only_ if you are really sure that listening daemon
+ cannot be tuned to accept connections faster. Enabling this
+ option can harm clients of your server.
-tcp_synack_retries - INTEGER
- Number of times SYNACKs for a passive TCP connection attempt will
- be retransmitted. Should not be higher than 255. Default value
- is 5, which corresponds to ~180seconds.
+tcp_adv_win_scale - INTEGER
+ Count buffering overhead as bytes/2^tcp_adv_win_scale
+ (if tcp_adv_win_scale > 0) or bytes-bytes/2^(-tcp_adv_win_scale),
+ if it is <= 0.
+ Default: 2
-tcp_keepalive_time - INTEGER
- How often TCP sends out keepalive messages when keepalive is enabled.
- Default: 2hours.
+tcp_allowed_congestion_control - STRING
+ Show/set the congestion control choices available to non-privileged
+ processes. The list is a subset of those listed in
+ tcp_available_congestion_control.
+ Default is "reno" and the default setting (tcp_congestion_control).
-tcp_keepalive_probes - INTEGER
- How many keepalive probes TCP sends out, until it decides that the
- connection is broken. Default value: 9.
+tcp_app_win - INTEGER
+ Reserve max(window/2^tcp_app_win, mss) of window for application
+ buffer. Value 0 is special, it means that nothing is reserved.
+ Default: 31
-tcp_keepalive_intvl - INTEGER
- How frequently the probes are send out. Multiplied by
- tcp_keepalive_probes it is time to kill not responding connection,
- after probes started. Default value: 75sec i.e. connection
- will be aborted after ~11 minutes of retries.
+tcp_available_congestion_control - STRING
+ Shows the available congestion control choices that are registered.
+ More congestion control algorithms may be available as modules,
+ but not loaded.
-tcp_retries1 - INTEGER
- How many times to retry before deciding that something is wrong
- and it is necessary to report this suspicion to network layer.
- Minimal RFC value is 3, it is default, which corresponds
- to ~3sec-8min depending on RTO.
+tcp_base_mss - INTEGER
+ The initial value of search_low to be used by the packetization layer
+ Path MTU discovery (MTU probing). If MTU probing is enabled,
+ this is the initial MSS used by the connection.
-tcp_retries2 - INTEGER
- How may times to retry before killing alive TCP connection.
- RFC1122 says that the limit should be longer than 100 sec.
- It is too small number. Default value 15 corresponds to ~13-30min
- depending on RTO.
+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.
+ Default is set as part of kernel configuration.
-tcp_orphan_retries - INTEGER
- How may times to retry before killing TCP connection, closed
- by our side. Default value 7 corresponds to ~50sec-16min
- depending on RTO. If you machine is loaded WEB server,
- you should think about lowering this value, such sockets
- may consume significant resources. Cf. tcp_max_orphans.
+tcp_dsack - BOOLEAN
+ Allows TCP to send "duplicate" SACKs.
+
+tcp_ecn - BOOLEAN
+ Enable Explicit Congestion Notification in TCP.
+
+tcp_fack - BOOLEAN
+ Enable FACK congestion avoidance and fast retransmission.
+ The value is not used, if tcp_sack is not enabled.
tcp_fin_timeout - INTEGER
Time to hold socket in state FIN-WAIT-2, if it was closed
because they eat maximum 1.5K of memory, but they tend
to live longer. Cf. tcp_max_orphans.
-tcp_max_tw_buckets - INTEGER
- Maximal number of timewait sockets held by system simultaneously.
- If this number is exceeded time-wait socket is immediately destroyed
- and warning is printed. This limit exists only to prevent
- simple DoS attacks, you _must_ not lower the limit artificially,
- but rather increase it (probably, after increasing installed memory),
- if network conditions require more than default value.
+tcp_frto - INTEGER
+ Enables Forward RTO-Recovery (F-RTO) defined in RFC4138.
+ F-RTO is an enhanced recovery algorithm for TCP retransmission
+ timeouts. It is particularly beneficial in wireless environments
+ where packet loss is typically due to random radio interference
+ rather than intermediate router congestion. F-RTO is sender-side
+ only modification. Therefore it does not require any support from
+ the peer.
+
+ If set to 1, basic version is enabled. 2 enables SACK enhanced
+ F-RTO if flow uses SACK. The basic version can be used also when
+ SACK is in use though scenario(s) with it exists where F-RTO
+ interacts badly with the packet counting of the SACK enabled TCP
+ flow.
+
+tcp_frto_response - INTEGER
+ When F-RTO has detected that a TCP retransmission timeout was
+ spurious (i.e, the timeout would have been avoided had TCP set a
+ longer retransmission timeout), TCP has several options what to do
+ next. Possible values are:
+ 0 Rate halving based; a smooth and conservative response,
+ results in halved cwnd and ssthresh after one RTT
+ 1 Very conservative response; not recommended because even
+ though being valid, it interacts poorly with the rest of
+ Linux TCP, halves cwnd and ssthresh immediately
+ 2 Aggressive response; undoes congestion control measures
+ that are now known to be unnecessary (ignoring the
+ possibility of a lost retransmission that would require
+ TCP to be more cautious), cwnd and ssthresh are restored
+ to the values prior timeout
+ Default: 0 (rate halving based)
-tcp_tw_recycle - BOOLEAN
- Enable fast recycling TIME-WAIT sockets. Default value is 0.
- It should not be changed without advice/request of technical
- experts.
+tcp_keepalive_time - INTEGER
+ How often TCP sends out keepalive messages when keepalive is enabled.
+ Default: 2hours.
-tcp_tw_reuse - BOOLEAN
- Allow to reuse TIME-WAIT sockets for new connections when it is
- safe from protocol viewpoint. Default value is 0.
- It should not be changed without advice/request of technical
- experts.
+tcp_keepalive_probes - INTEGER
+ How many keepalive probes TCP sends out, until it decides that the
+ connection is broken. Default value: 9.
+
+tcp_keepalive_intvl - INTEGER
+ How frequently the probes are send out. Multiplied by
+ tcp_keepalive_probes it is time to kill not responding connection,
+ after probes started. Default value: 75sec i.e. connection
+ will be aborted after ~11 minutes of retries.
+
+tcp_low_latency - BOOLEAN
+ If set, the TCP stack makes decisions that prefer lower
+ latency as opposed to higher throughput. By default, this
+ option is not set meaning that higher throughput is preferred.
+ An example of an application where this default should be
+ changed would be a Beowulf compute cluster.
+ Default: 0
tcp_max_orphans - INTEGER
Maximal number of TCP sockets not attached to any user file handle,
more aggressively. Let me to remind again: each orphan eats
up to ~64K of unswappable memory.
-tcp_abort_on_overflow - BOOLEAN
- If listening service is too slow to accept new connections,
- reset them. Default state is FALSE. It means that if overflow
- occurred due to a burst, connection will recover. Enable this
- option _only_ if you are really sure that listening daemon
- cannot be tuned to accept connections faster. Enabling this
- option can harm clients of your server.
-
-tcp_syncookies - BOOLEAN
- Only valid when the kernel was compiled with CONFIG_SYNCOOKIES
- Send out syncookies when the syn backlog queue of a socket
- overflows. This is to prevent against the common 'syn flood attack'
- Default: FALSE
-
- Note, that syncookies is fallback facility.
- It MUST NOT be used to help highly loaded servers to stand
- against legal connection rate. If you see synflood warnings
- in your logs, but investigation shows that they occur
- because of overload with legal connections, you should tune
- another parameters until this warning disappear.
- See: tcp_max_syn_backlog, tcp_synack_retries, tcp_abort_on_overflow.
-
- syncookies seriously violate TCP protocol, do not allow
- to use TCP extensions, can result in serious degradation
- of some services (f.e. SMTP relaying), visible not by you,
- but your clients and relays, contacting you. While you see
- synflood warnings in logs not being really flooded, your server
- is seriously misconfigured.
-
-tcp_stdurg - BOOLEAN
- Use the Host requirements interpretation of the TCP urg pointer field.
- Most hosts use the older BSD interpretation, so if you turn this on
- Linux might not communicate correctly with them.
- Default: FALSE
-
tcp_max_syn_backlog - INTEGER
Maximal number of remembered connection requests, which are
still did not receive an acknowledgment from connecting client.
and 128 for low memory machines. If server suffers of overload,
try to increase this number.
-tcp_window_scaling - BOOLEAN
- Enable window scaling as defined in RFC1323.
+tcp_max_tw_buckets - INTEGER
+ Maximal number of timewait sockets held by system simultaneously.
+ If this number is exceeded time-wait socket is immediately destroyed
+ and warning is printed. This limit exists only to prevent
+ simple DoS attacks, you _must_ not lower the limit artificially,
+ but rather increase it (probably, after increasing installed memory),
+ if network conditions require more than default value.
-tcp_timestamps - BOOLEAN
- Enable timestamps as defined in RFC1323.
+tcp_mem - vector of 3 INTEGERs: min, pressure, max
+ min: below this number of pages TCP is not bothered about its
+ memory appetite.
-tcp_sack - BOOLEAN
- Enable select acknowledgments (SACKS).
+ pressure: when amount of memory allocated by TCP exceeds this number
+ of pages, TCP moderates its memory consumption and enters memory
+ pressure mode, which is exited when memory consumption falls
+ under "min".
-tcp_fack - BOOLEAN
- Enable FACK congestion avoidance and fast retransmission.
- The value is not used, if tcp_sack is not enabled.
+ max: number of pages allowed for queueing by all TCP sockets.
-tcp_dsack - BOOLEAN
- Allows TCP to send "duplicate" SACKs.
+ Defaults are calculated at boot time from amount of available
+ memory.
-tcp_ecn - BOOLEAN
- Enable Explicit Congestion Notification in TCP.
+tcp_moderate_rcvbuf - BOOLEAN
+ If set, TCP performs receive buffer auto-tuning, attempting to
+ automatically size the buffer (no greater than tcp_rmem[2]) to
+ match the size required by the path for full throughput. Enabled by
+ default.
+
+tcp_mtu_probing - INTEGER
+ Controls TCP Packetization-Layer Path MTU Discovery. Takes three
+ values:
+ 0 - Disabled
+ 1 - Disabled by default, enabled when an ICMP black hole detected
+ 2 - Always enabled, use initial MSS of tcp_base_mss.
+
+tcp_no_metrics_save - BOOLEAN
+ By default, TCP saves various connection metrics in the route cache
+ when the connection closes, so that connections established in the
+ near future can use these to set initial conditions. Usually, this
+ increases overall performance, but may sometimes cause performance
+ degradation. If set, TCP will not cache metrics on closing
+ connections.
+
+tcp_orphan_retries - INTEGER
+ How may times to retry before killing TCP connection, closed
+ by our side. Default value 7 corresponds to ~50sec-16min
+ depending on RTO. If you machine is loaded WEB server,
+ you should think about lowering this value, such sockets
+ may consume significant resources. Cf. tcp_max_orphans.
tcp_reordering - INTEGER
Maximal reordering of packets in a TCP stream.
On retransmit try to send bigger packets to work around bugs in
certain TCP stacks.
-tcp_wmem - vector of 3 INTEGERs: min, default, max
- min: Amount of memory reserved for send buffers for TCP socket.
- Each TCP socket has rights to use it due to fact of its birth.
- Default: 4K
+tcp_retries1 - INTEGER
+ How many times to retry before deciding that something is wrong
+ and it is necessary to report this suspicion to network layer.
+ Minimal RFC value is 3, it is default, which corresponds
+ to ~3sec-8min depending on RTO.
- default: Amount of memory allowed for send buffers for TCP socket
- by default. This value overrides net.core.wmem_default used
- by other protocols, it is usually lower than net.core.wmem_default.
- Default: 16K
+tcp_retries2 - INTEGER
+ How may times to retry before killing alive TCP connection.
+ RFC1122 says that the limit should be longer than 100 sec.
+ It is too small number. Default value 15 corresponds to ~13-30min
+ depending on RTO.
- max: Maximal amount of memory allowed for automatically selected
- send buffers for TCP socket. This value does not override
- net.core.wmem_max, "static" selection via SO_SNDBUF does not use this.
- Default: 128K
+tcp_rfc1337 - BOOLEAN
+ If set, the TCP stack behaves conforming to RFC1337. If unset,
+ we are not conforming to RFC, but prevent TCP TIME_WAIT
+ assassination.
+ Default: 0
tcp_rmem - vector of 3 INTEGERs: min, default, max
min: Minimal size of receive buffer used by TCP sockets.
pressure.
Default: 8K
- default: default size of receive buffer used by TCP sockets.
+ default: initial size of receive buffer used by TCP sockets.
This value overrides net.core.rmem_default used by other protocols.
Default: 87380 bytes. This value results in window of 65535 with
default setting of tcp_adv_win_scale and tcp_app_win:0 and a bit
max: maximal size of receive buffer allowed for automatically
selected receiver buffers for TCP socket. This value does not override
- net.core.rmem_max, "static" selection via SO_RCVBUF does not use this.
- Default: 87380*2 bytes.
+ net.core.rmem_max. Calling setsockopt() with SO_RCVBUF disables
+ automatic tuning of that socket's receive buffer size, in which
+ case this value is ignored.
+ Default: between 87380B and 4MB, depending on RAM size.
-tcp_mem - vector of 3 INTEGERs: min, pressure, max
- min: below this number of pages TCP is not bothered about its
- memory appetite.
+tcp_sack - BOOLEAN
+ Enable select acknowledgments (SACKS).
- pressure: when amount of memory allocated by TCP exceeds this number
- of pages, TCP moderates its memory consumption and enters memory
- pressure mode, which is exited when memory consumption falls
- under "min".
+tcp_slow_start_after_idle - BOOLEAN
+ If set, provide RFC2861 behavior and time out the congestion
+ window after an idle period. An idle period is defined at
+ the current RTO. If unset, the congestion window will not
+ be timed out after an idle period.
+ Default: 1
- max: number of pages allowed for queueing by all TCP sockets.
+tcp_stdurg - BOOLEAN
+ Use the Host requirements interpretation of the TCP urgent pointer field.
+ Most hosts use the older BSD interpretation, so if you turn this on
+ Linux might not communicate correctly with them.
+ Default: FALSE
- Defaults are calculated at boot time from amount of available
- memory.
+tcp_synack_retries - INTEGER
+ Number of times SYNACKs for a passive TCP connection attempt will
+ be retransmitted. Should not be higher than 255. Default value
+ is 5, which corresponds to ~180seconds.
-tcp_app_win - INTEGER
- Reserve max(window/2^tcp_app_win, mss) of window for application
- buffer. Value 0 is special, it means that nothing is reserved.
- Default: 31
+tcp_syncookies - BOOLEAN
+ Only valid when the kernel was compiled with CONFIG_SYNCOOKIES
+ Send out syncookies when the syn backlog queue of a socket
+ overflows. This is to prevent against the common 'SYN flood attack'
+ Default: FALSE
-tcp_adv_win_scale - INTEGER
- Count buffering overhead as bytes/2^tcp_adv_win_scale
- (if tcp_adv_win_scale > 0) or bytes-bytes/2^(-tcp_adv_win_scale),
- if it is <= 0.
- Default: 2
+ Note, that syncookies is fallback facility.
+ It MUST NOT be used to help highly loaded servers to stand
+ against legal connection rate. If you see SYN flood warnings
+ in your logs, but investigation shows that they occur
+ because of overload with legal connections, you should tune
+ another parameters until this warning disappear.
+ See: tcp_max_syn_backlog, tcp_synack_retries, tcp_abort_on_overflow.
-tcp_rfc1337 - BOOLEAN
- If set, the TCP stack behaves conforming to RFC1337. If unset,
- we are not conforming to RFC, but prevent TCP TIME_WAIT
- assassination.
- Default: 0
+ syncookies seriously violate TCP protocol, do not allow
+ to use TCP extensions, can result in serious degradation
+ of some services (f.e. SMTP relaying), visible not by you,
+ but your clients and relays, contacting you. While you see
+ SYN flood warnings in logs not being really flooded, your server
+ is seriously misconfigured.
-tcp_low_latency - BOOLEAN
- If set, the TCP stack makes decisions that prefer lower
- latency as opposed to higher throughput. By default, this
- option is not set meaning that higher throughput is preferred.
- An example of an application where this default should be
- changed would be a Beowulf compute cluster.
- Default: 0
+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
+ is 5, which corresponds to ~180seconds.
+
+tcp_timestamps - BOOLEAN
+ Enable timestamps as defined in RFC1323.
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: 3
-
-tcp_frto - BOOLEAN
- Enables F-RTO, an enhanced recovery algorithm for TCP retransmission
- timeouts. It is particularly beneficial in wireless environments
- where packet loss is typically due to random radio interference
- rather than intermediate router congestion.
+ 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: 3
-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.
+tcp_tw_recycle - BOOLEAN
+ Enable fast recycling TIME-WAIT sockets. Default value is 0.
+ It should not be changed without advice/request of technical
+ experts.
-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_tw_reuse - BOOLEAN
+ Allow to reuse TIME-WAIT sockets for new connections when it is
+ safe from protocol viewpoint. Default value is 0.
+ It should not be changed without advice/request of technical
+ experts.
+
+tcp_window_scaling - BOOLEAN
+ Enable window scaling as defined in RFC1323.
+
+tcp_wmem - vector of 3 INTEGERs: min, default, max
+ min: Amount of memory reserved for send buffers for TCP sockets.
+ Each TCP socket has rights to use it due to fact of its birth.
+ Default: 4K
+
+ default: initial size of send buffer used by TCP sockets. This
+ value overrides net.core.wmem_default used by other protocols.
+ It is usually lower than net.core.wmem_default.
+ Default: 16K
+
+ max: Maximal amount of memory allowed for automatically tuned
+ send buffers for TCP sockets. This value does not override
+ net.core.wmem_max. Calling setsockopt() with SO_SNDBUF disables
+ automatic tuning of that socket's send buffer size, in which case
+ this value is ignored.
+ Default: between 64K and 4MB, depending on RAM size.
tcp_workaround_signed_windows - BOOLEAN
If set, assume no receipt of a window scaling option means the
not receive a window scaling option from them.
Default: 0
-tcp_slow_start_after_idle - BOOLEAN
- If set, provide RFC2861 behavior and time out the congestion
- window after an idle period. An idle period is defined at
- the current RTO. If unset, the congestion window will not
- be timed out after an idle period.
- Default: 1
+tcp_dma_copybreak - INTEGER
+ Lower limit, in bytes, of the size of socket reads that will be
+ offloaded to a DMA copy engine, if one is present in the system
+ and CONFIG_NET_DMA is enabled.
+ Default: 4096
+
+UDP variables:
+
+udp_mem - vector of 3 INTEGERs: min, pressure, max
+ Number of pages allowed for queueing by all UDP sockets.
+
+ min: Below this number of pages UDP is not bothered about its
+ memory appetite. When amount of memory allocated by UDP exceeds
+ this number, UDP starts to moderate memory usage.
+
+ pressure: This value was introduced to follow format of tcp_mem.
+
+ max: Number of pages allowed for queueing by all UDP sockets.
+
+ Default is calculated at boot time from amount of available memory.
+
+udp_rmem_min - INTEGER
+ Minimal size of receive buffer used by UDP sockets in moderation.
+ Each UDP socket is able to use the size for receiving data, even if
+ total pages of UDP sockets exceed udp_mem pressure. The unit is byte.
+ Default: 4096
+
+udp_wmem_min - INTEGER
+ Minimal size of send buffer used by UDP sockets in moderation.
+ Each UDP socket is able to use the size for sending data, even if
+ total pages of UDP sockets exceed udp_mem pressure. The unit is byte.
+ Default: 4096
CIPSOv4 Variables:
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.
+ has one will be used regardless of this setting.
Default: 0
Allows you to write a number, which can be used as required.
Default value is 0.
-(1) Jiffie: internal timeunit for the kernel. On the i386 1/100s, on the
-Alpha 1/1024s. See the HZ define in /usr/include/asm/param.h for the exact
-value on your system.
-
Alexey Kuznetsov.
kuznet@ms2.inr.ac.ru
disabled if accept_ra is disabled.
accept_ra_pinfo - BOOLEAN
- Learn Prefix Inforamtion in Router Advertisement.
+ Learn Prefix Information in Router Advertisement.
Functional default: enabled if accept_ra is enabled.
disabled if accept_ra is disabled.
Functional default: enabled if local forwarding is disabled.
disabled if local forwarding is enabled.
+accept_source_route - INTEGER
+ Accept source routing (routing extension header).
+
+ >= 0: Accept only routing header type 2.
+ < 0: Do not accept routing header.
+
+ Default: 0
+
autoconf - BOOLEAN
Autoconfigure addresses using Prefix Information in Router
Advertisements.
Default: 1
bridge-nf-filter-vlan-tagged - BOOLEAN
- 1 : pass bridged vlan-tagged ARP/IP traffic to arptables/iptables.
+ 1 : pass bridged vlan-tagged ARP/IP/IPv6 traffic to {arp,ip,ip6}tables.
+ 0 : disable this.
+ Default: 1
+
+bridge-nf-filter-pppoe-tagged - BOOLEAN
+ 1 : pass bridged pppoe-tagged IP/IPv6 traffic to {ip,ip6}tables.
0 : disable this.
Default: 1
+proc/sys/net/sctp/* Variables:
+
+addip_enable - BOOLEAN
+ Enable or disable extension of Dynamic Address Reconfiguration
+ (ADD-IP) functionality specified in RFC5061. This extension provides
+ the ability to dynamically add and remove new addresses for the SCTP
+ associations.
+
+ 1: Enable extension.
+
+ 0: Disable extension.
+
+ Default: 0
+
+addip_noauth_enable - BOOLEAN
+ Dynamic Address Reconfiguration (ADD-IP) requires the use of
+ authentication to protect the operations of adding or removing new
+ addresses. This requirement is mandated so that unauthorized hosts
+ would not be able to hijack associations. However, older
+ implementations may not have implemented this requirement while
+ allowing the ADD-IP extension. For reasons of interoperability,
+ we provide this variable to control the enforcement of the
+ authentication requirement.
+
+ 1: Allow ADD-IP extension to be used without authentication. This
+ should only be set in a closed environment for interoperability
+ with older implementations.
+
+ 0: Enforce the authentication requirement
+
+ Default: 0
+
+auth_enable - BOOLEAN
+ Enable or disable Authenticated Chunks extension. This extension
+ provides the ability to send and receive authenticated chunks and is
+ required for secure operation of Dynamic Address Reconfiguration
+ (ADD-IP) extension.
+
+ 1: Enable this extension.
+ 0: Disable this extension.
+
+ Default: 0
+
+prsctp_enable - BOOLEAN
+ Enable or disable the Partial Reliability extension (RFC3758) which
+ is used to notify peers that a given DATA should no longer be expected.
+
+ 1: Enable extension
+ 0: Disable
+
+ Default: 1
+
+max_burst - INTEGER
+ The limit of the number of new packets that can be initially sent. It
+ controls how bursty the generated traffic can be.
+
+ Default: 4
+
+association_max_retrans - INTEGER
+ Set the maximum number for retransmissions that an association can
+ attempt deciding that the remote end is unreachable. If this value
+ is exceeded, the association is terminated.
+
+ Default: 10
+
+max_init_retransmits - INTEGER
+ The maximum number of retransmissions of INIT and COOKIE-ECHO chunks
+ that an association will attempt before declaring the destination
+ unreachable and terminating.
+
+ Default: 8
+
+path_max_retrans - INTEGER
+ The maximum number of retransmissions that will be attempted on a given
+ path. Once this threshold is exceeded, the path is considered
+ unreachable, and new traffic will use a different path when the
+ association is multihomed.
+
+ Default: 5
+
+rto_initial - INTEGER
+ The initial round trip timeout value in milliseconds that will be used
+ in calculating round trip times. This is the initial time interval
+ for retransmissions.
+
+ Default: 3000
+
+rto_max - INTEGER
+ The maximum value (in milliseconds) of the round trip timeout. This
+ is the largest time interval that can elapse between retransmissions.
+
+ Default: 60000
+
+rto_min - INTEGER
+ The minimum value (in milliseconds) of the round trip timeout. This
+ is the smallest time interval the can elapse between retransmissions.
+
+ Default: 1000
+
+hb_interval - INTEGER
+ The interval (in milliseconds) between HEARTBEAT chunks. These chunks
+ are sent at the specified interval on idle paths to probe the state of
+ a given path between 2 associations.
+
+ Default: 30000
+
+sack_timeout - INTEGER
+ The amount of time (in milliseconds) that the implementation will wait
+ to send a SACK.
+
+ Default: 200
+
+valid_cookie_life - INTEGER
+ The default lifetime of the SCTP cookie (in milliseconds). The cookie
+ is used during association establishment.
+
+ Default: 60000
+
+cookie_preserve_enable - BOOLEAN
+ Enable or disable the ability to extend the lifetime of the SCTP cookie
+ that is used during the establishment phase of SCTP association
+
+ 1: Enable cookie lifetime extension.
+ 0: Disable
+
+ Default: 1
+
+rcvbuf_policy - INTEGER
+ Determines if the receive buffer is attributed to the socket or to
+ association. SCTP supports the capability to create multiple
+ associations on a single socket. When using this capability, it is
+ possible that a single stalled association that's buffering a lot
+ of data may block other associations from delivering their data by
+ consuming all of the receive buffer space. To work around this,
+ the rcvbuf_policy could be set to attribute the receiver buffer space
+ to each association instead of the socket. This prevents the described
+ blocking.
+
+ 1: rcvbuf space is per association
+ 0: recbuf space is per socket
+
+ Default: 0
+
+sndbuf_policy - INTEGER
+ Similar to rcvbuf_policy above, this applies to send buffer space.
+
+ 1: Send buffer is tracked per association
+ 0: Send buffer is tracked per socket.
+
+ Default: 0
+
+sctp_mem - vector of 3 INTEGERs: min, pressure, max
+ Number of pages allowed for queueing by all SCTP sockets.
+
+ min: Below this number of pages SCTP is not bothered about its
+ memory appetite. When amount of memory allocated by SCTP exceeds
+ this number, SCTP starts to moderate memory usage.
+
+ pressure: This value was introduced to follow format of tcp_mem.
+
+ max: Number of pages allowed for queueing by all SCTP sockets.
+
+ Default is calculated at boot time from amount of available memory.
+
+sctp_rmem - vector of 3 INTEGERs: min, default, max
+ See tcp_rmem for a description.
+
+sctp_wmem - vector of 3 INTEGERs: min, default, max
+ See tcp_wmem for a description.
+
UNDOCUMENTED:
-dev_weight FIXME
-discovery_slots FIXME
-discovery_timeout FIXME
-fast_poll_increase FIXME
-ip6_queue_maxlen FIXME
-lap_keepalive_time FIXME
-lo_cong FIXME
-max_baud_rate FIXME
-max_dgram_qlen FIXME
-max_noreply_time FIXME
-max_tx_data_size FIXME
-max_tx_window FIXME
-min_tx_turn_time FIXME
-mod_cong FIXME
-no_cong FIXME
-no_cong_thresh FIXME
-slot_timeout FIXME
-warn_noreply_time FIXME
-
-$Id: ip-sysctl.txt,v 1.20 2001/12/13 09:00:18 davem Exp $
+/proc/sys/net/core/*
+ dev_weight FIXME
+
+/proc/sys/net/unix/*
+ max_dgram_qlen FIXME
+
+/proc/sys/net/irda/*
+ fast_poll_increase FIXME
+ warn_noreply_time FIXME
+ discovery_slots FIXME
+ slot_timeout FIXME
+ max_baud_rate FIXME
+ discovery_timeout FIXME
+ lap_keepalive_time FIXME
+ max_noreply_time FIXME
+ max_tx_data_size FIXME
+ max_tx_window FIXME
+ min_tx_turn_time FIXME
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff