mirror of
https://github.com/octoleo/syncthing.git
synced 2024-12-22 02:48:59 +00:00
120 lines
4.1 KiB
Groff
120 lines
4.1 KiB
Groff
.\" Man page generated from reStructuredText.
|
|
.
|
|
.
|
|
.nr rst2man-indent-level 0
|
|
.
|
|
.de1 rstReportMargin
|
|
\\$1 \\n[an-margin]
|
|
level \\n[rst2man-indent-level]
|
|
level margin: \\n[rst2man-indent\\n[rst2man-indent-level]]
|
|
-
|
|
\\n[rst2man-indent0]
|
|
\\n[rst2man-indent1]
|
|
\\n[rst2man-indent2]
|
|
..
|
|
.de1 INDENT
|
|
.\" .rstReportMargin pre:
|
|
. RS \\$1
|
|
. nr rst2man-indent\\n[rst2man-indent-level] \\n[an-margin]
|
|
. nr rst2man-indent-level +1
|
|
.\" .rstReportMargin post:
|
|
..
|
|
.de UNINDENT
|
|
. RE
|
|
.\" indent \\n[an-margin]
|
|
.\" old: \\n[rst2man-indent\\n[rst2man-indent-level]]
|
|
.nr rst2man-indent-level -1
|
|
.\" new: \\n[rst2man-indent\\n[rst2man-indent-level]]
|
|
.in \\n[rst2man-indent\\n[rst2man-indent-level]]u
|
|
..
|
|
.TH "SYNCTHING-LOCALDISCO" "7" "Dec 14, 2024" "v1.28.1" "Syncthing"
|
|
.SH NAME
|
|
syncthing-localdisco \- Local Discovery Protocol v4
|
|
.SH MODE OF OPERATION
|
|
.sp
|
|
Each participating device periodically sends an Announcement packet. It also
|
|
keeps a table of the announcements it has seen. There is no way to solicit a
|
|
reply; the only message type is Announcement.
|
|
.sp
|
|
On multihomed hosts the announcement packets should be sent on each interface
|
|
on which Syncthing will accept connections.
|
|
.sp
|
|
The announcement packet is sent over UDP.
|
|
.sp
|
|
For IPv4, the Announcement packet is broadcast either to the link\-specific
|
|
broadcast address, or to the generic link\-local broadcast address
|
|
\fB255.255.255.255\fP, with destination port 21027.
|
|
.sp
|
|
For IPv6, the Announcement packet is multicast to the transient link\-local
|
|
multicast address \fBff12::8384\fP, with destination port 21027.
|
|
.sp
|
|
It is recommended that local discovery Announcement packets be sent on a 30
|
|
to 60 second interval, possibly with immediate transmissions when a
|
|
previously unknown device is discovered or a device has restarted (see the
|
|
\fBinstance_id\fP field).
|
|
.SH DEVICE ID
|
|
.sp
|
|
The device ID is the SHA\-256 (32 bytes) of the device X.509 certificate. See
|
|
\fI\%Understanding Device IDs\fP in the Syncthing documentation.
|
|
.SH ANNOUNCEMENT PACKET
|
|
.sp
|
|
The Announcement packet has the following structure:
|
|
.INDENT 0.0
|
|
.INDENT 3.5
|
|
.sp
|
|
.EX
|
|
0 1 2 3
|
|
0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
|
|
+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+
|
|
| Magic |
|
|
+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+
|
|
/ /
|
|
\e Announce Message \e
|
|
/ /
|
|
+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+\-+
|
|
.EE
|
|
.UNINDENT
|
|
.UNINDENT
|
|
.sp
|
|
There is no explicit length field as the length is given by the length of
|
|
the discovery announcement packet itself.
|
|
.sp
|
|
The Magic field is a 32 bit word representing 0x2EA7D90B in network (big
|
|
endian) byte order. It identifies the packet as being a Syncthing discovery
|
|
protocol packet.
|
|
.sp
|
|
The Announce Message contents are in protocol buffer format using the
|
|
following schema:
|
|
.INDENT 0.0
|
|
.INDENT 3.5
|
|
.sp
|
|
.EX
|
|
message Announce {
|
|
bytes id = 1;
|
|
repeated string addresses = 2;
|
|
int64 instance_id = 3;
|
|
}
|
|
.EE
|
|
.UNINDENT
|
|
.UNINDENT
|
|
.sp
|
|
The \fBid\fP field contains the Device ID of the sending device.
|
|
.sp
|
|
The \fBaddresses\fP field contains a list of addresses where the device can be
|
|
contacted. Direct connections will typically have the \fBtcp://\fP scheme.
|
|
Relay connections will typically use the \fBrelay://\fP scheme.
|
|
.sp
|
|
When interpreting addresses with an unspecified address, e.g.,
|
|
\fBtcp://0.0.0.0:22000\fP or \fBtcp://:42424\fP, the source address of the
|
|
discovery announcement is to be used.
|
|
.sp
|
|
The \fBinstance_id\fP field is set to a randomly generated ID at client
|
|
startup. Other devices on the network can detect a change in instance ID
|
|
between two announces and conclude that the announcing device has restarted.
|
|
.SH AUTHOR
|
|
The Syncthing Authors
|
|
.SH COPYRIGHT
|
|
2014-2019, The Syncthing Authors
|
|
.\" Generated by docutils manpage writer.
|
|
.
|