:~$ syncthing start
Usage:
syncthing [options]
Options:
-audit Write events to audit file
-auditfile="" Specify audit file (use “-” for stdout, “–” for stderr)
-browser-only Open GUI in browser
-generate="" Generate key and config in specified dir, then exit
-gui-address="" Override GUI address (e.g. “http://192.0.2.42:8443”)
-gui-apikey="" Override GUI API key
-home="" Set configuration directory
-logfile="-" Log file name (use “-” for stdout)
-logflags=“2” Select information in log line prefix (see below)
-no-browser Do not start browser
-no-restart Disable monitor process, managed restarts and log file writing
-paths Show configuration paths
-paused Start with all devices and folders paused
-reset-database Reset the database, forcing a full rescan and resync
-reset-deltas Reset delta index IDs, forcing a full index exchange
-unpaused Start with all devices and folders unpaused
-upgrade Perform upgrade
-upgrade-check Check for available upgrade
-upgrade-to="" Force upgrade directly from specified URL
-verbose Print verbose log output
-version Show version
The -logflags value is a sum of the following:
1 Date
2 Time
4 Microsecond time
8 Long filename
16 Short filename
I.e. to prefix each log line with date and time, set -logflags=3 (1 + 2 from
above). The value 0 is used to disable all of the above. The default is to
show time only (2).
Development Settings
The following environment variables modify Syncthing’s behavior in ways that
are mostly useful for developers. Use with care.
STNODEFAULTFOLDER Don’t create a default folder when starting for the first
time. This variable will be ignored anytime after the first
run.
STGUIASSETS Directory to load GUI assets from. Overrides compiled in
assets.
STTRACE A comma separated string of facilities to trace. The valid
facility strings listed below.
STPROFILER Set to a listen address such as “127.0.0.1:9090” to start
the profiler with HTTP access.
STCPUPROFILE Write a CPU profile to cpu-$pid.pprof on exit.
STHEAPPROFILE Write heap profiles to heap-$pid-$timestamp.pprof each time
heap usage increases.
STBLOCKPROFILE Write block profiles to block-$pid-$timestamp.pprof every 20
seconds.
STPERFSTATS Write running performance statistics to perf-$pid.csv. Not
supported on Windows.
STDEADLOCK Used for debugging internal deadlocks. Use only under
direction of a developer.
STDEADLOCKTIMEOUT Used for debugging internal deadlocks; sets debug
sensitivity. Use only under direction of a developer.
STDEADLOCKTHRESHOLD Used for debugging internal deadlocks; sets debug
sensitivity. Use only under direction of a developer.
STNORESTART Equivalent to the -no-restart argument. Disable the
Syncthing monitor process which handles restarts for some
configuration changes, upgrades, crashes and also log file
writing (stdout is still written).
STNOUPGRADE Disable automatic upgrades.
STHASHING Select the SHA256 hashing package to use. Possible values
are “standard” for the Go standard library implementation,
“minio” for the github.com/minio/sha256-simd implementation,
and blank (the default) for auto detection.
GOMAXPROCS Set the maximum number of CPU cores to use. Defaults to all
available CPU cores.
GOGC Percentage of heap growth at which to trigger GC. Default is
100. Lower numbers keep peak memory usage down, at the price
of CPU usage (i.e. performance).
Debugging Facilities
The following are valid values for the STTRACE variable:
beacon - Multicast and broadcast discovery
config - Configuration loading and saving
connections - Connection handling
db - The database layer
dialer - Dialing connections
discover - Remote device discovery
events - Event generation and logging
http - REST API
main - Main package
model - The root hub
nat - NAT discovery and port mapping
pmp - NAT-PMP discovery and port mapping
protocol - The BEP protocol
scanner - File change detection and hashing
sha256 - SHA256 hashing package
stats - Persistent device and folder statistics
sync - Mutexes
upgrade - Binary upgrades
upnp - UPnP discovery and port mapping
versioner - File versioning