Syncthing Configuration

Syncthing Configuration

Synopsis

$HOME/.config/syncthing
$HOME/Library/Application Support/Syncthing
%LOCALAPPDATA%\Syncthing

Description

New in version 1.5.0: Database and config can now be set separately. Previously the database was always located in the same directory as the config.

Syncthing uses a single directory to store configuration and crypto keys. Syncthing also has a database, which is often stored in this directory too. The config location defaults to $HOME/.config/syncthing (Unix-like), $HOME/Library/Application Support/Syncthing (Mac), or %LOCALAPPDATA%\Syncthing (Windows). It can be changed at runtime using the --config flag. In this directory the following files are located:

config.xml

The configuration file, in XML format.

cert.pem, key.pem

The device’s ECDSA public and private key. These form the basis for the device ID. The key must be kept private.

https-cert.pem, https-key.pem

The certificate and key for HTTPS GUI connections. These may be replaced with a custom certificate for HTTPS as desired.

csrftokens.txt

A list of recently issued CSRF tokens (for protection against browser cross site request forgery).

The database is stored either in the same directory as the config (usually the default), but may also be located in one of the following directories (Unix-like platforms only):

If a database exists in the old default location, that location is still used.
If $XDG_DATA_HOME is set, use $XDG_DATA_HOME/syncthing.
If ~/.local/share/syncthing exists, use that location.
Use the old default location (same as config).

The location of the database can be changed using the --data flag. The --home flag sets both config and database locations at the same time. The database contains the following files:

index-***.db

A directory holding the database with metadata and hashes of the files currently on disk and available from peers.

Config File Format

The following shows an example of a default configuration file (IDs will differ):

Note

The config examples are present for illustration. Do not copy them entirely to use as your config. They are likely out-of-date and the values may no longer correspond to the defaults.

<configuration version="30">
    <folder id="default" label="Default Folder" path="/Users/jb/Sync/" type="sendreceive" rescanIntervalS="3600" fsWatcherEnabled="true" fsWatcherDelayS="10" ignorePerms="false" autoNormalize="true">
        <filesystemType>basic</filesystemType>
        <device id="3LT2GA5-CQI4XJM-WTZ264P-MLOGMHL-MCRLDNT-MZV4RD3-KA745CL-OGAERQZ"></device>
        <minDiskFree unit="%">1</minDiskFree>
        <versioning></versioning>
        <copiers>0</copiers>
        <pullerMaxPendingKiB>0</pullerMaxPendingKiB>
        <hashers>0</hashers>
        <order>random</order>
        <ignoreDelete>false</ignoreDelete>
        <scanProgressIntervalS>0</scanProgressIntervalS>
        <pullerPauseS>0</pullerPauseS>
        <maxConflicts>-1</maxConflicts>
        <disableSparseFiles>false</disableSparseFiles>
        <disableTempIndexes>false</disableTempIndexes>
        <paused>false</paused>
        <weakHashThresholdPct>25</weakHashThresholdPct>
        <markerName>.stfolder</markerName>
        <copyOwnershipFromParent>false</copyOwnershipFromParent>
        <modTimeWindowS>0</modTimeWindowS>
        <maxConcurrentWrites>2</maxConcurrentWrites>
        <disableFsync>false</disableFsync>
        <blockPullOrder>standard</blockPullOrder>
        <copyRangeMethod>standard</copyRangeMethod>
    </folder>
    <device id="3LT2GA5-CQI4XJM-WTZ264P-MLOGMHL-MCRLDNT-MZV4RD3-KA745CL-OGAERQZ" name="syno" compression="metadata" introducer="false" skipIntroductionRemovals="false" introducedBy="">
        <address>dynamic</address>
        <paused>false</paused>
        <autoAcceptFolders>false</autoAcceptFolders>
        <maxSendKbps>0</maxSendKbps>
        <maxRecvKbps>0</maxRecvKbps>
        <maxRequestKiB>0</maxRequestKiB>
        <remoteGUIPort>0</remoteGUIPort>
    </device>
    <gui enabled="true" tls="false" debugging="false">
        <address>127.0.0.1:8384</address>
        <apikey>k1dnz1Dd0rzTBjjFFh7CXPnrF12C49B1</apikey>
        <theme>default</theme>
    </gui>
    <ldap></ldap>
    <options>
        <listenAddress>default</listenAddress>
        <globalAnnounceServer>default</globalAnnounceServer>
        <globalAnnounceEnabled>true</globalAnnounceEnabled>
        <localAnnounceEnabled>true</localAnnounceEnabled>
        <localAnnouncePort>21027</localAnnouncePort>
        <localAnnounceMCAddr>[ff12::8384]:21027</localAnnounceMCAddr>
        <maxSendKbps>0</maxSendKbps>
        <maxRecvKbps>0</maxRecvKbps>
        <reconnectionIntervalS>60</reconnectionIntervalS>
        <relaysEnabled>true</relaysEnabled>
        <relayReconnectIntervalM>10</relayReconnectIntervalM>
        <startBrowser>true</startBrowser>
        <natEnabled>true</natEnabled>
        <natLeaseMinutes>60</natLeaseMinutes>
        <natRenewalMinutes>30</natRenewalMinutes>
        <natTimeoutSeconds>10</natTimeoutSeconds>
        <urAccepted>0</urAccepted>
        <urSeen>0</urSeen>
        <urUniqueID></urUniqueID>
        <urURL>https://data.syncthing.net/newdata</urURL>
        <urPostInsecurely>false</urPostInsecurely>
        <urInitialDelayS>1800</urInitialDelayS>
        <restartOnWakeup>true</restartOnWakeup>
        <autoUpgradeIntervalH>12</autoUpgradeIntervalH>
        <upgradeToPreReleases>false</upgradeToPreReleases>
        <keepTemporariesH>24</keepTemporariesH>
        <cacheIgnoredFiles>false</cacheIgnoredFiles>
        <progressUpdateIntervalS>5</progressUpdateIntervalS>
        <limitBandwidthInLan>false</limitBandwidthInLan>
        <minHomeDiskFree unit="%">1</minHomeDiskFree>
        <releasesURL>https://upgrades.syncthing.net/meta.json</releasesURL>
        <overwriteRemoteDeviceNamesOnConnect>false</overwriteRemoteDeviceNamesOnConnect>
        <tempIndexMinBlocks>10</tempIndexMinBlocks>
        <trafficClass>0</trafficClass>
        <defaultFolderPath>~</defaultFolderPath>
        <setLowPriority>true</setLowPriority>
        <maxFolderConcurrency>0</maxFolderConcurrency>
        <crashReportingURL>https://crash.syncthing.net/newcrash</crashReportingURL>
        <crashReportingEnabled>true</crashReportingEnabled>
        <stunKeepaliveStartS>180</stunKeepaliveStartS>
        <stunKeepaliveMinS>20</stunKeepaliveMinS>
        <stunServer>default</stunServer>
        <databaseTuning>auto</databaseTuning>
        <maxConcurrentIncomingRequestKiB>0</maxConcurrentIncomingRequestKiB>
    </options>
</configuration>

Configuration Element

<configuration version="30">
    <folder></folder>
    <device></device>
    <gui></gui>
    <ldap></ldap>
    <options></options>
    <ignoredDevice>5SYI2FS-LW6YAXI-JJDYETS-NDBBPIO-256MWBO-XDPXWVG-24QPUM4-PDW4UQU</ignoredDevice>
    <ignoredFolder>bd7q3-zskm5</ignoredFolder>
</configuration>

This is the root element. It has one attribute:

version

The config version. Increments whenever a change is made that requires migration from previous formats.

It contains the elements described in the following sections and these two additional child elements:

ignoredDevice

Contains the ID of the device that should be ignored. Connection attempts from this device are logged to the console but never displayed in the web GUI.

ignoredFolder

Contains the ID of the folder that should be ignored. This folder will always be skipped when advertised from a remote device, i.e. this will be logged, but there will be no dialog about it in the web GUI.

Folder Element

<folder id="default" label="Default Folder" path="/Users/jb/Sync/" type="sendreceive" rescanIntervalS="3600" fsWatcherEnabled="true" fsWatcherDelayS="10" ignorePerms="false" autoNormalize="true">
    <filesystemType>basic</filesystemType>
    <device id="3LT2GA5-CQI4XJM-WTZ264P-MLOGMHL-MCRLDNT-MZV4RD3-KA745CL-OGAERQZ"></device>
    <minDiskFree unit="%">1</minDiskFree>
    <versioning></versioning>
    <copiers>0</copiers>
    <pullerMaxPendingKiB>0</pullerMaxPendingKiB>
    <hashers>0</hashers>
    <order>random</order>
    <ignoreDelete>false</ignoreDelete>
    <scanProgressIntervalS>0</scanProgressIntervalS>
    <pullerPauseS>0</pullerPauseS>
    <maxConflicts>-1</maxConflicts>
    <disableSparseFiles>false</disableSparseFiles>
    <disableTempIndexes>false</disableTempIndexes>
    <paused>false</paused>
    <weakHashThresholdPct>25</weakHashThresholdPct>
    <markerName>.stfolder</markerName>
    <copyOwnershipFromParent>false</copyOwnershipFromParent>
    <modTimeWindowS>0</modTimeWindowS>
    <maxConcurrentWrites>2</maxConcurrentWrites>
    <disableFsync>false</disableFsync>
    <blockPullOrder>standard</blockPullOrder>
    <copyRangeMethod>standard</copyRangeMethod>
</folder>

One or more folder elements must be present in the file. Each element describes one folder. The following attributes may be set on the folder element:

The folder ID, must be unique. (mandatory)

label

The label of a folder is a human readable and descriptive local name. May be different on each device, empty, and/or identical to other folder labels. (optional)

path

The path to the directory where the folder is stored on this device; not sent to other devices. (mandatory)

type

Controls how the folder is handled by Syncthing. Possible values are:

sendreceive

The folder is in default mode. Sending local and accepting remote changes. Note that this type was previously called “readwrite” which is deprecated but still accepted in incoming configs.

sendonly

The folder is in “send only” mode – it will not be modified by Syncthing on this device. Note that this type was previously called “readonly” which is deprecated but still accepted in incoming configs.

receiveonly

The folder is in “receive only” mode – it will not propagate changes to other devices.

rescanIntervalS

The rescan interval, in seconds. Can be set to zero to disable when external plugins are used to trigger rescans.

fsWatcherEnabled

If enabled this detects changes to files in the folder and scans them.

fsWatcherDelayS

The duration during which changes detected are accumulated, before a scan is scheduled (only takes effect if fsWatcherEnabled is true).

ignorePerms

True if the folder should ignore permissions.

autoNormalize

Automatically correct UTF-8 normalization errors found in file names.

The following child elements may exist:

device

These must have the id attribute and can have an introducedBy attribute, identifying the device that introduced us to share this folder with the given device. If the original introducer unshares this folder with this device, our device will follow and unshare the folder (subject to skipIntroductionRemovals being false on the introducer device). All mentioned devices are those that will be sharing the folder in question. Each mentioned device must have a separate device element later in the file. It is customary that the local device ID is included in all folders. Syncthing will currently add this automatically if it is not present in the configuration file.

minDiskFree

The minimum required free space that should be available on the disk this folder resides. The folder will be stopped when the value drops below the threshold. Accepted units are %, kB, MB, GB and TB. Set to zero to disable.

versioning

Specifies a versioning configuration.

Device Element

<device id="5SYI2FS-LW6YAXI-JJDYETS-NDBBPIO-256MWBO-XDPXWVG-24QPUM4-PDW4UQU" name="syno" compression="metadata" introducer="false" skipIntroductionRemovals="false" introducedBy="2CYF2WQ-AKZO2QZ-JAKWLYD-AGHMQUM-BGXUOIS-GYILW34-HJG3DUK-LRRYQAR">
    <address>dynamic</address>
    <paused>false</paused>
    <autoAcceptFolders>false</autoAcceptFolders>
    <maxSendKbps>0</maxSendKbps>
    <maxRecvKbps>0</maxRecvKbps>
    <maxRequestKiB>0</maxRequestKiB>
    <remoteGUIPort>0</remoteGUIPort>
</device>
<device id="2CYF2WQ-AKZO2QZ-JAKWLYD-AGHMQUM-BGXUOIS-GYILW34-HJG3DUK-LRRYQAR" name="syno local" compression="metadata" introducer="false" skipIntroductionRemovals="false" introducedBy="">
    <address>tcp://192.0.2.1:22001</address>
    <paused>true</paused>
    <allowedNetwork>192.168.0.0/16</allowedNetwork>
    <autoAcceptFolders>false</autoAcceptFolders>
    <maxSendKbps>100</maxSendKbps>
    <maxRecvKbps>100</maxRecvKbps>
    <maxRequestKiB>65536</maxRequestKiB>
    <remoteGUIPort>8384</remoteGUIPort>
</device>

One or more device elements must be present in the file. Each element describes a device participating in the cluster. It is customary to include a device element for the local device; Syncthing will currently add one if it is not present. The following attributes may be set on the device element:

The device ID. (mandatory)

name

A friendly name for the device. (optional)

compression

Whether to use protocol compression when sending messages to this device. The possible values are:

metadata

Compress metadata packets, such as index information. Metadata is usually very compression friendly so this is a good default.

always

Compress all packets, including file data. This is recommended if the folders contents are mainly compressible data such as documents or text files.

never

Disable all compression.

introducer

Set to true if this device should be trusted as an introducer, i.e. we should copy their list of devices per folder when connecting.

GUI Element

<gui enabled="true" tls="false" debugging="false">
    <address>127.0.0.1:8384</address>
    <apikey>l7jSbCqPD95JYZ0g8vi4ZLAMg3ulnN1b</apikey>
    <theme>default</theme>
</gui>

There must be exactly one gui element. The GUI configuration is also used by the REST API and the Event API. The following attributes may be set on the gui element:

enabled

If not true, the GUI and API will not be started.

tls

If set to true, TLS (HTTPS) will be enforced. Non-HTTPS requests will be redirected to HTTPS. When this is set to false, TLS connections are still possible but it is not mandatory.

debugging

This enables Profiling and additional debugging endpoints in the REST API.

The following child elements may be present:

address

Set the listen address. One address element must be present. Allowed address formats are:

IPv4 address and port (127.0.0.1:8384)

The address and port is used as given.

IPv6 address and port ([::1]:8384)

The address and port is used as given. The address must be enclosed in square brackets.

Wildcard and port (0.0.0.0:12345, [::]:12345, :12345)

These are equivalent and will result in Syncthing listening on all interfaces via both IPv4 and IPv6.

UNIX socket location (/var/run/st.sock)

If the address is an absolute path it is interpreted as the path to a UNIX socket. (Added in v0.14.52.)

unixSocketPermissions

In the case that a UNIX socket location is used for address, set this to an octal to override the default permissions of the socket.

user

Set to require authentication.

password

Contains the bcrypt hash of the real password.

apikey

If set, this is the API key that enables usage of the REST interface.

insecureAdminAccess

If true, this allows access to the web GUI from outside (i.e. not localhost) without authorization. A warning will displayed about this setting on startup.

theme

The name of the theme to use.

authMode

Authentication mode to use. If not present authentication mode (static) is controlled by presence of user/password fields for backward compatibility.

static

Authentication using user and password.

ldap

LDAP authentication. Requires ldap top level config section to be present.

LDAP Element

<ldap>
    <address>localhost:389</address>
    <bindDN>cn=%s,ou=users,dc=syncthing,dc=net</bindDN>
    <transport>nontls</transport>
    <insecureSkipVerify>false</insecureSkipVerify>
</ldap>

The ldap element contains LDAP configuration options.

address

LDAP server address (server:port).

bindDN

BindDN for user authentication. Special %s variable should be used to pass username to LDAP.

transport

nontls

Non secure connection.

tls

TLS secured connection.

starttls

StartTLS connection mode.

insecureSkipVerify

Skip verification (true or false).

Options Element

<options>
    <listenAddress>default</listenAddress>
    <globalAnnounceServer>default</globalAnnounceServer>
    <globalAnnounceEnabled>true</globalAnnounceEnabled>
    <localAnnounceEnabled>true</localAnnounceEnabled>
    <localAnnouncePort>21027</localAnnouncePort>
    <localAnnounceMCAddr>[ff12::8384]:21027</localAnnounceMCAddr>
    <maxSendKbps>0</maxSendKbps>
    <maxRecvKbps>0</maxRecvKbps>
    <reconnectionIntervalS>60</reconnectionIntervalS>
    <relaysEnabled>true</relaysEnabled>
    <relayReconnectIntervalM>10</relayReconnectIntervalM>
    <startBrowser>true</startBrowser>
    <natEnabled>true</natEnabled>
    <natLeaseMinutes>60</natLeaseMinutes>
    <natRenewalMinutes>30</natRenewalMinutes>
    <natTimeoutSeconds>10</natTimeoutSeconds>
    <urAccepted>0</urAccepted>
    <urSeen>0</urSeen>
    <urUniqueID></urUniqueID>
    <urURL>https://data.syncthing.net/newdata</urURL>
    <urPostInsecurely>false</urPostInsecurely>
    <urInitialDelayS>1800</urInitialDelayS>
    <restartOnWakeup>true</restartOnWakeup>
    <autoUpgradeIntervalH>12</autoUpgradeIntervalH>
    <upgradeToPreReleases>false</upgradeToPreReleases>
    <keepTemporariesH>24</keepTemporariesH>
    <cacheIgnoredFiles>false</cacheIgnoredFiles>
    <progressUpdateIntervalS>5</progressUpdateIntervalS>
    <limitBandwidthInLan>false</limitBandwidthInLan>
    <minHomeDiskFree unit="%">1</minHomeDiskFree>
    <releasesURL>https://upgrades.syncthing.net/meta.json</releasesURL>
    <overwriteRemoteDeviceNamesOnConnect>false</overwriteRemoteDeviceNamesOnConnect>
    <tempIndexMinBlocks>10</tempIndexMinBlocks>
    <trafficClass>0</trafficClass>
    <defaultFolderPath>~</defaultFolderPath>
    <setLowPriority>true</setLowPriority>
    <maxFolderConcurrency>0</maxFolderConcurrency>
    <crashReportingURL>https://crash.syncthing.net/newcrash</crashReportingURL>
    <crashReportingEnabled>true</crashReportingEnabled>
    <stunKeepaliveStartS>180</stunKeepaliveStartS>
    <stunKeepaliveMinS>20</stunKeepaliveMinS>
    <stunServer>default</stunServer>
    <databaseTuning>auto</databaseTuning>
    <maxConcurrentIncomingRequestKiB>0</maxConcurrentIncomingRequestKiB>
</options>

The options element contains all other global configuration options.

listenAddress

The listen address for incoming sync connections. See Listen Addresses for allowed syntax.

globalAnnounceServer

A URI to a global announce (discovery) server, or the word default to include the default servers. Any number of globalAnnounceServer elements may be present. The syntax for non-default entries is that of a HTTP or HTTPS URL. A number of options may be added as query options to the URL: insecure to prevent certificate validation (required for HTTP URLs) and id=<device ID> to perform certificate pinning. The device ID to use is printed by the discovery server on startup.

globalAnnounceEnabled

Whether to announce this device to the global announce (discovery) server, and also use it to look up other devices.

localAnnounceEnabled

Whether to send announcements to the local LAN, also use such announcements to find other devices.

localAnnouncePort

The port on which to listen and send IPv4 broadcast announcements to.

localAnnounceMCAddr

The group address and port to join and send IPv6 multicast announcements on.

maxSendKbps

Outgoing data rate limit, in kibibytes per second.

maxRecvKbps

Incoming data rate limits, in kibibytes per second.

reconnectionIntervalS

The number of seconds to wait between each attempt to connect to currently unconnected devices.

relaysEnabled

When true, relays will be connected to and potentially used for device to device connections.

relayReconnectIntervalM

Sets the interval, in minutes, between relay reconnect attempts.

startBrowser

Whether to attempt to start a browser to show the GUI when Syncthing starts.

natEnabled

Whether to attempt to perform a UPnP and NAT-PMP port mapping for incoming sync connections.

natLeaseMinutes

Request a lease for this many minutes; zero to request a permanent lease.

natRenewalMinutes

Attempt to renew the lease after this many minutes.

natTimeoutSeconds

When scanning for UPnP devices, wait this long for responses.

urAccepted

Whether the user has accepted to submit anonymous usage data. The default, 0, mean the user has not made a choice, and Syncthing will ask at some point in the future. -1 means no, a number above zero means that that version of usage reporting has been accepted.

urSeen

The highest usage reporting version that has already been shown in the web GUI.

urUniqueID

The unique ID sent together with the usage report. Generated when usage reporting is enabled.

urURL

The URL to post usage report data to, when enabled.

urPostInsecurely

When true, the UR URL can be http instead of https, or have a self-signed certificate. The default is false.

urInitialDelayS

The time to wait from startup to the first usage report being sent. Allows the system to stabilize before reporting statistics.

restartOnWakeup

Whether to perform a restart of Syncthing when it is detected that we are waking from sleep mode (i.e. a folded up laptop).

autoUpgradeIntervalH

Check for a newer version after this many hours. Set to zero to disable automatic upgrades.

upgradeToPreReleases

If true, automatic upgrades include release candidates (see Versions & Releases).

keepTemporariesH

Keep temporary failed transfers for this many hours. While the temporaries are kept, the data they contain need not be transferred again.

cacheIgnoredFiles

Whether to cache the results of ignore pattern evaluation. Performance at the price of memory. Defaults to false as the cost for evaluating ignores is usually not significant.

progressUpdateIntervalS

How often in seconds the progress of ongoing downloads is made available to the GUI.

limitBandwidthInLan

Whether to apply bandwidth limits to devices in the same broadcast domain as the local device.

minHomeDiskFree

The minimum required free space that should be available on the partition holding the configuration and index. Accepted units are %, kB, MB, GB and TB.

releasesURL

The URL from which release information is loaded, for automatic upgrades.

alwaysLocalNet

Network that should be considered as local given in CIDR notation.

overwriteRemoteDeviceNamesOnConnect

If set, device names will always be overwritten with the name given by remote on each connection. By default, the name that the remote device announces will only be adopted when a name has not already been set.

tempIndexMinBlocks

When exchanging index information for incomplete transfers, only take into account files that have at least this many blocks.

unackedNotificationID

ID of a notification to be displayed in the web GUI. Will be removed once the user acknowledged it (e.g. an transition notice on an upgrade).

trafficClass

Specify a type of service (TOS)/traffic class of outgoing packets.

stunServer

Server to be used for STUN, given as ip:port. The keyword default gets expanded to stun.callwithus.com:3478, stun.counterpath.com:3478, stun.counterpath.net:3478, stun.ekiga.net:3478, stun.ideasip.com:3478, stun.internetcalls.com:3478, stun.schlund.de:3478, stun.sipgate.net:10000, stun.sipgate.net:3478, stun.voip.aebc.com:3478, stun.voiparound.com:3478, stun.voipbuster.com:3478, stun.voipstunt.com:3478 and stun.xten.com:3478 (this is the default).

stunKeepaliveSeconds

Interval in seconds between contacting a STUN server to maintain NAT mapping. Default is 24 and you can set it to 0 to disable contacting STUN servers.

defaultFolderPath

The UI will propose to create new folders at this path. This can be disabled by setting this to an empty string.

setLowPriority

Syncthing will attempt to lower its process priority at startup. Specifically: on Linux, set itself to a separate process group, set the niceness level of that process group to nine and the I/O priority to best effort level five; on other Unixes, set the process niceness level to nine; on Windows, set the process priority class to below normal. To disable this behavior, for example to control process priority yourself as part of launching Syncthing, set this option to false.

Listen Addresses

The following address types are accepted in sync protocol listen addresses. If you want Syncthing to listen on multiple addresses, you can either: add multiple <listenAddress> tags in the configuration file or enter several addresses separated by commas in the GUI.

Default listen addresses (default)

This is equivalent to tcp://0.0.0.0:22000, quic://0.0.0.0:22000 and dynamic+https://relays.syncthing.net/endpoint.

TCP wildcard and port (tcp://0.0.0.0:22000, tcp://:22000)

These are equivalent and will result in Syncthing listening on all interfaces, IPv4 and IPv6, on the specified port.

TCP IPv4 wildcard and port (tcp4://0.0.0.0:22000, tcp4://:22000)

These are equivalent and will result in Syncthing listening on all interfaces via IPv4 only.

TCP IPv4 address and port (tcp4://192.0.2.1:22000)

This results in Syncthing listening on the specified address and port, IPv4 only.

TCP IPv6 wildcard and port (tcp6://[::]:22000, tcp6://:22000)

These are equivalent and will result in Syncthing listening on all interfaces via IPv6 only.

TCP IPv6 address and port (tcp6://[2001:db8::42]:22000)

This results in Syncthing listening on the specified address and port, IPv6 only.

QUIC address and port (e.g. quic://0.0.0.0:22000)

Syntax is the same as for TCP, also quic4 and quic6 can be used.

Static relay address (relay://192.0.2.42:22067?id=abcd123...)

Syncthing will connect to and listen for incoming connections via the specified relay address.

Todo

Document available URL parameters.

Dynamic relay pool (dynamic+https://192.0.2.42/relays)

Syncthing will fetch the specified HTTPS URL, parse it for a JSON payload describing relays, select a relay from the available ones and listen via that as if specified as a static relay above.

Todo

Document available URL parameters.

Syncing Configuration Files

Syncing configuration files between devices (such that multiple devices are using the same configuration files) can cause issues. This is easy to do accidentally if you sync your home folder between devices. A common symptom of syncing configuration files is two devices ending up with the same Device ID.

If you want to use Syncthing to backup your configuration files, it is recommended that the files you are backing up are in a Send Only Folder to prevent other devices from overwriting the per device configuration. The folder on the remote device(s) should not be used as configuration for the remote devices.

If you’d like to sync your home folder in non-send only mode, you may add the folder that stores the configuration files to the ignore list. If you’d also like to backup your configuration files, add another folder in send only mode for just the configuration folder.