1.. SPDX-License-Identifier: GPL-2.0
2
3=====================
4MPTCP Sysfs variables
5=====================
6
7/proc/sys/net/mptcp/* Variables
8===============================
9
10enabled - BOOLEAN
11	Control whether MPTCP sockets can be created.
12
13	MPTCP sockets can be created if the value is 1. This is a
14	per-namespace sysctl.
15
16	Default: 1 (enabled)
17
18add_addr_timeout - INTEGER (seconds)
19	Set the timeout after which an ADD_ADDR control message will be
20	resent to an MPTCP peer that has not acknowledged a previous
21	ADD_ADDR message.
22
23	The default value matches TCP_RTO_MAX. This is a per-namespace
24	sysctl.
25
26	Default: 120
27
28checksum_enabled - BOOLEAN
29	Control whether DSS checksum can be enabled.
30
31	DSS checksum can be enabled if the value is nonzero. This is a
32	per-namespace sysctl.
33
34	Default: 0
35
36allow_join_initial_addr_port - BOOLEAN
37	Allow peers to send join requests to the IP address and port number used
38	by the initial subflow if the value is 1. This controls a flag that is
39	sent to the peer at connection time, and whether such join requests are
40	accepted or denied.
41
42	Joins to addresses advertised with ADD_ADDR are not affected by this
43	value.
44
45	This is a per-namespace sysctl.
46
47	Default: 1
48
49pm_type - INTEGER
50
51	Set the default path manager type to use for each new MPTCP
52	socket. In-kernel path management will control subflow
53	connections and address advertisements according to
54	per-namespace values configured over the MPTCP netlink
55	API. Userspace path management puts per-MPTCP-connection subflow
56	connection decisions and address advertisements under control of
57	a privileged userspace program, at the cost of more netlink
58	traffic to propagate all of the related events and commands.
59
60	This is a per-namespace sysctl.
61
62	* 0 - In-kernel path manager
63	* 1 - Userspace path manager
64
65	Default: 0
66
67stale_loss_cnt - INTEGER
68	The number of MPTCP-level retransmission intervals with no traffic and
69	pending outstanding data on a given subflow required to declare it stale.
70	The packet scheduler ignores stale subflows.
71	A low stale_loss_cnt  value allows for fast active-backup switch-over,
72	an high value maximize links utilization on edge scenarios e.g. lossy
73	link with high BER or peer pausing the data processing.
74
75	This is a per-namespace sysctl.
76
77	Default: 4
78