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Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1.. SPDX-License-Identifier: GPL-2.0
2
3=====================
4MPTCP Sysfs variables
5=====================
6
7/proc/sys/net/mptcp/* Variables
8===============================
9
10add_addr_timeout - INTEGER (seconds)
11 Set the timeout after which an ADD_ADDR control message will be
12 resent to an MPTCP peer that has not acknowledged a previous
13 ADD_ADDR message.
14
15 Do not retransmit if set to 0.
16
17 The default value matches TCP_RTO_MAX. This is a per-namespace
18 sysctl.
19
20 Default: 120
21
22allow_join_initial_addr_port - BOOLEAN
23 Allow peers to send join requests to the IP address and port number used
24 by the initial subflow if the value is 1. This controls a flag that is
25 sent to the peer at connection time, and whether such join requests are
26 accepted or denied.
27
28 Joins to addresses advertised with ADD_ADDR are not affected by this
29 value.
30
31 This is a per-namespace sysctl.
32
33 Default: 1
34
35available_path_managers - STRING
36 Shows the available path managers choices that are registered. More
37 path managers may be available, but not loaded.
38
39available_schedulers - STRING
40 Shows the available schedulers choices that are registered. More packet
41 schedulers may be available, but not loaded.
42
43blackhole_timeout - INTEGER (seconds)
44 Initial time period in second to disable MPTCP on active MPTCP sockets
45 when a MPTCP firewall blackhole issue happens. This time period will
46 grow exponentially when more blackhole issues get detected right after
47 MPTCP is re-enabled and will reset to the initial value when the
48 blackhole issue goes away.
49
50 0 to disable the blackhole detection. This is a per-namespace sysctl.
51
52 Default: 3600
53
54checksum_enabled - BOOLEAN
55 Control whether DSS checksum can be enabled.
56
57 DSS checksum can be enabled if the value is nonzero. This is a
58 per-namespace sysctl.
59
60 Default: 0
61
62close_timeout - INTEGER (seconds)
63 Set the make-after-break timeout: in absence of any close or
64 shutdown syscall, MPTCP sockets will maintain the status
65 unchanged for such time, after the last subflow removal, before
66 moving to TCP_CLOSE.
67
68 The default value matches TCP_TIMEWAIT_LEN. This is a per-namespace
69 sysctl.
70
71 Default: 60
72
73enabled - BOOLEAN
74 Control whether MPTCP sockets can be created.
75
76 MPTCP sockets can be created if the value is 1. This is a
77 per-namespace sysctl.
78
79 Default: 1 (enabled)
80
81path_manager - STRING
82 Set the default path manager name to use for each new MPTCP
83 socket. In-kernel path management will control subflow
84 connections and address advertisements according to
85 per-namespace values configured over the MPTCP netlink
86 API. Userspace path management puts per-MPTCP-connection subflow
87 connection decisions and address advertisements under control of
88 a privileged userspace program, at the cost of more netlink
89 traffic to propagate all of the related events and commands.
90
91 This is a per-namespace sysctl.
92
93 * "kernel" - In-kernel path manager
94 * "userspace" - Userspace path manager
95
96 Default: "kernel"
97
98pm_type - INTEGER
99 Set the default path manager type to use for each new MPTCP
100 socket. In-kernel path management will control subflow
101 connections and address advertisements according to
102 per-namespace values configured over the MPTCP netlink
103 API. Userspace path management puts per-MPTCP-connection subflow
104 connection decisions and address advertisements under control of
105 a privileged userspace program, at the cost of more netlink
106 traffic to propagate all of the related events and commands.
107
108 This is a per-namespace sysctl.
109
110 Deprecated since v6.15, use path_manager instead.
111
112 * 0 - In-kernel path manager
113 * 1 - Userspace path manager
114
115 Default: 0
116
117scheduler - STRING
118 Select the scheduler of your choice.
119
120 Support for selection of different schedulers. This is a per-namespace
121 sysctl.
122
123 Default: "default"
124
125stale_loss_cnt - INTEGER
126 The number of MPTCP-level retransmission intervals with no traffic and
127 pending outstanding data on a given subflow required to declare it stale.
128 The packet scheduler ignores stale subflows.
129 A low stale_loss_cnt value allows for fast active-backup switch-over,
130 an high value maximize links utilization on edge scenarios e.g. lossy
131 link with high BER or peer pausing the data processing.
132
133 This is a per-namespace sysctl.
134
135 Default: 4
136
137syn_retrans_before_tcp_fallback - INTEGER
138 The number of SYN + MP_CAPABLE retransmissions before falling back to
139 TCP, i.e. dropping the MPTCP options. In other words, if all the packets
140 are dropped on the way, there will be:
141
142 * The initial SYN with MPTCP support
143 * This number of SYN retransmitted with MPTCP support
144 * The next SYN retransmissions will be without MPTCP support
145
146 0 means the first retransmission will be done without MPTCP options.
147 >= 128 means that all SYN retransmissions will keep the MPTCP options. A
148 lower number might increase false-positive MPTCP blackholes detections.
149 This is a per-namespace sysctl.
150
151 Default: 2