1SYNCTHING-FAQ(7) Syncthing SYNCTHING-FAQ(7)
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6 syncthing-faq - Frequently Asked Questions
7 • General
9 • What is Syncthing?
11 • Is it “syncthing”, “Syncthing” or “SyncThing”?
13 • What things are synced?
15 • Is synchronization fast?
17 • How does Syncthing differ from BitTorrent/Resilio Sync?
19 • Is there an iOS client?
21 • Should I keep my device IDs secret?
23 • Troubleshooting
25 • Where are the Syncthing logs?
27 • Why is the sync so slow?
29 • Why does it use so much CPU?
31 • Why is the setup more complicated than BitTorrent/Resilio Sync?
33 • Why do I get “Host check error” in the GUI/API?
35 • My Syncthing database is corrupt
37 • Why do I see Syncthing twice in task manager?
39 • How can I view the history of changes?
41 • Does the audit log contain every change?
43 • Why does Syncthing connect to this unknown/suspicious address?
45 • I am seeing the error message “folder marker missing”. What do I
47 do?
48 • Usage
50 • What if there is a conflict?
52 • How do I serve a folder from a read only filesystem?
54 • I really hate the .stfolder directory, can I remove it?
56 • Am I able to nest shared folders in Syncthing?
58 • How do I rename/move a synced folder?
60 • How do I configure multiple users on a single machine?
62 • Does Syncthing support syncing between folders on the same system?
64 • When I do have two distinct Syncthing-managed folders on two hosts,
66 how does Syncthing handle moving files between them?
67 • Can I help initial sync by copying files manually?
69 • Is Syncthing my ideal backup application?
71 • How can I exclude files with brackets ([]) in the name?
73 • How do I access the web GUI from another computer?
75 • I don’t like the GUI or the theme. Can it be changed?
77 • How do I upgrade Syncthing?
79 • Where do I find the latest release?
81 • How do I run Syncthing as a daemon process on Linux?
83 • How do I increase the inotify limit to get my filesystem watcher to
85 work?
86 • How do I reset the GUI password?
88
90 What is Syncthing?
91 Syncthing is an application that lets you synchronize your files across
92 multiple devices. This means the creation, modification or deletion of
93 files on one machine will automatically be replicated to your other de‐
94 vices. We believe your data is your data alone and you deserve to
95 choose where it is stored. Therefore Syncthing does not upload your
96 data to the cloud but exchanges your data across your machines as soon
97 as they are online at the same time.
98 Is it “syncthing”, “Syncthing” or “SyncThing”?
100 It’s Syncthing, although the command and source repository is spelled
101 syncthing so it may be referred to in that way as well. It’s definitely
102 not SyncThing, even though the abbreviation st is used in some circum‐
103 stances and file names.
104 What things are synced?
106 The following things are always synchronized:
107 • File contents
109 • File modification times
111 The following may be synchronized or not, depending:
113 • File permissions (when supported by file system; on Windows only the
115 read only bit is synchronized)
116 • Symbolic links (synced, except on Windows, but never followed)
118 • File or directory owners and groups (when enabled)
120 • Extended attributes (when enabled)
122 • POSIX or NFS ACLs (as part of extended attributes)
124 The following are not synchronized;
126 • Directory modification times (not preserved)
128 • Hard links (followed, not preserved)
130 • Windows junctions (synced as ordinary directories; require enabling
132 in the configuration on a per-folder basis)
133 • Resource forks (not preserved)
135 • Windows ACLs (not preserved)
137 • Devices, FIFOs, and other specials (ignored)
139 • Sparse file sparseness (will become sparse, when supported by the OS
141 & filesystem)
142 • Syncthing internal files and folders (e.g. .stfolder, .stignore,
144 .stversions, temporary files, etc.)
145 Is synchronization fast?
147 Syncthing segments files into pieces, called blocks, to transfer data
148 from one device to another. Therefore, multiple devices can share the
149 synchronization load, in a similar way to the torrent protocol. The
150 more devices you have online, the faster an additional device will re‐
151 ceive the data because small blocks will be fetched from all devices in
152 parallel.
153 Syncthing handles renaming files and updating their metadata in an ef‐
155 ficient manner. This means that renaming a file will not cause a re‐
156 transmission of that file. Additionally, appending data to existing
157 files should be handled efficiently as well.
158 Temporary files are used to store partial data downloaded from other
160 devices. They are automatically removed whenever a file transfer has
161 been completed or after the configured amount of time which is set in
162 the configuration file (24 hours by default).
163 How does Syncthing differ from BitTorrent/Resilio Sync?
165 The two are different and not related. Syncthing and BitTorrent/Resilio
166 Sync accomplish some of the same things, namely syncing files between
167 two or more computers.
168 BitTorrent Sync, now called Resilio Sync, is a proprietary peer-to-peer
170 file synchronization tool available for Windows, Mac, Linux, Android,
171 iOS, Windows Phone, Amazon Kindle Fire and BSD. [1] Syncthing is an
172 open source file synchronization tool.
173 Syncthing uses an open and documented protocol, and likewise the secu‐
175 rity mechanisms in use are well defined and visible in the source code.
176 Resilio Sync uses an undocumented, closed protocol with unknown secu‐
177 rity properties.
178 [1] https://en.wikipedia.org/wiki/Resilio_Sync
180 Is there an iOS client?
182 There are no plans by the current Syncthing team to officially support
183 iOS in the foreseeable future.
184 iOS has significant restrictions on background processing that make it
186 very hard to run Syncthing reliably and integrate it into the system.
187 However, there is a commercial packaging of Syncthing for iOS that at‐
189 tempts to work within these limitations. [2]
190 [2] https://www.mobiussync.com
192 Should I keep my device IDs secret?
194 No. The IDs are not sensitive. Given a device ID it’s possible to find
195 the IP address for that device, if global discovery is enabled on it.
196 Knowing the device ID doesn’t help you actually establish a connection
197 to that device or get a list of files, etc.
198 For a connection to be established, both devices need to know about the
200 other’s device ID. It’s not possible (in practice) to forge a device
201 ID. (To forge a device ID you need to create a TLS certificate with
202 that specific SHA-256 hash. If you can do that, you can spoof any TLS
203 certificate. The world is your oyster!)
204 SEE ALSO:
206 Understanding Device IDs
207
209 Where are the Syncthing logs?
210 Syncthing logs to stdout by default. On Windows Syncthing by default
211 also creates syncthing.log in Syncthing’s home directory (run syncthing
212 --paths to see where that is). The command line option --logfile can be
213 used to specify a user-defined logfile. If you only have access to a
214 running instance’s GUI, check under the Actions - About menu item to
215 see the used paths.
216 If you’re running a process manager like systemd, check there. If
218 you’re using a GUI wrapper integration, it may keep the logs for you.
219 Why is the sync so slow?
221 When troubleshooting a slow sync, there are a number of things to
222 check.
223 First of all, verify that you are not connected via a relay. In the
225 “Remote Devices” list on the right side of the GUI, double check that
226 you see “Address: <some address>” and not “Relay: <some address>”.
227 [image]
228 If you are connected via a relay, this is because a direct connection
230 could not be established. Double check and follow the suggestions in
231 Firewall Setup to enable direct connections.
232 Second, if one of the devices is a very low powered machine (a Rasp‐
234 berry Pi, or a phone, or a NAS, or similar) you are likely constrained
235 by the CPU on that device. See the next question for reasons Syncthing
236 likes a faster CPU.
237 Third, verify that the network connection is OK. Tools such as iperf or
239 just an Internet speed test can be used to verify the performance here.
240 Why does it use so much CPU?
242 1. When new or changed files are detected, or Syncthing starts for the
243 first time, your files are hashed using SHA-256.
244 2. Data that is sent over the network is compressed (optionally) and
246 encrypted (always). When receiving data it must be decrypted and
247 then (if compressed) decompressed.
248 3. There is a certain amount of housekeeping that must be done to track
250 the current and available versions of each file in the index data‐
251 base.
252 4. By default Syncthing uses periodic scanning every hour when watching
254 for changes or every minute if that’s disabled to detect file
255 changes. This means checking every file’s modification time and com‐
256 paring it to the database. This can cause spikes of CPU usage for
257 large folders.
258 Hashing, compression and encryption cost CPU time. Also, using the GUI
260 causes a certain amount of extra CPU usage to calculate the summary
261 data it presents. Note however that once things are in sync CPU usage
262 should be negligible.
263 To minimize the impact of this, Syncthing attempts to lower the process
265 priority when starting up.
266 To further limit the amount of CPU used when syncing and scanning, set
268 the environment variable GOMAXPROCS to the maximum number of CPU cores
269 Syncthing should use at any given moment. For example, GOMAXPROCS=2 on
270 a machine with four cores will limit Syncthing to no more than half the
271 system’s CPU power.
272 Why is the setup more complicated than BitTorrent/Resilio Sync?
274 Security over convenience. In Syncthing you have to setup both sides to
275 connect two devices. An attacker can’t do much with a stolen device ID,
276 because you have to add the device on the other side too. You have bet‐
277 ter control where your files are transferred.
278 This is an area that we are working to improve in the long term.
280 Why do I get “Host check error” in the GUI/API?
282 Since version 0.14.6 Syncthing does an extra security check when the
283 GUI/API is bound to localhost - namely that the browser is talking to
284 localhost. This protects against most forms of DNS rebinding attack
285 <https://en.wikipedia.org/wiki/DNS_rebinding> against the GUI.
286 To pass this test, ensure that you are accessing the GUI using an URL
288 that begins with http://localhost, http://127.0.0.1 or http://[::1].
289 HTTPS is fine too, of course.
290 If you are using a proxy in front of Syncthing you may need to disable
292 this check, after ensuring that the proxy provides sufficient authenti‐
293 cation to protect against unauthorized access. Either:
294 • Make sure the proxy sets a Host header containing localhost, or
296 • Set gui.insecureSkipHostcheck in the advanced settings, or
298 • Bind the GUI/API to a non-localhost listen port.
300 In all cases, username/password authentication and HTTPS should be
302 used.
303 My Syncthing database is corrupt
305 This is almost always a result of bad RAM, storage device or other
306 hardware. When the index database is found to be corrupt Syncthing
307 cannot operate and will note this in the logs and exit. To overcome
308 this delete the database folder inside Syncthing’s data directory and
309 re-start Syncthing. It will then need to perform a full re-hashing of
310 all shared folders. You should check your system in case the underlying
311 cause is indeed faulty hardware which may put the system at risk of
312 further data loss.
313 Why do I see Syncthing twice in task manager?
315 One process manages the other, to capture logs and manage restarts.
316 This makes it easier to handle upgrades from within Syncthing itself,
317 and also ensures that we get a nice log file to help us narrow down the
318 cause for crashes and other bugs.
319 How can I view the history of changes?
321 The web GUI contains a Recent Changes button under the device list
322 which displays changes since the last (re)start of Syncthing. With the
323 --audit option you can enable a persistent, detailed log of changes and
324 most activities, which contains a JSON formatted sequence of events in
325 the ~/.config/syncthing/audit-_date_-_time_.log file.
326 Does the audit log contain every change?
328 The audit log (and the Recent Changes window) sees the changes that
329 your Syncthing sees. When Syncthing is continuously connected it usu‐
330 ally sees every change happening immediately and thus knows which node
331 initiated the change. When topology gets complex or when your node re‐
332 connects after some time offline, Syncthing synchronises with its
333 neighbours: It gets the latest synchronised state from the neighbour,
334 which is the result of all the changes between the last known state
335 (before disconnect or network delay) and the current state at the
336 neighbour, and if there were updates, deletes, creates, conflicts,
337 which were overlapping we only see the latest change for a given file
338 or directory (and the node where that latest change occurred). When we
339 connect to multiple neighbours Syncthing decides which neighbour has
340 the latest state, or if the states conflict it initiates the conflict
341 resolution procedure, which in the end results in a consistent
342 up-to-date state with all the neighbours.
343 Why does Syncthing connect to this unknown/suspicious address?
345 If you see outgoing connections to odd and unexpected addresses these
346 are most likely connections to relay servers. Relay servers are run by
347 volunteers all over the world. They usually listen on ports 443 or
348 22067, though this is controlled by the user running it. You can com‐
349 pare the address you are concerned about with the current list of ac‐
350 tive relays <https://relays.syncthing.net>. Relays do not and can not
351 see the data transmitted via them.
352 I am seeing the error message “folder marker missing”. What do I do?
354 Syncthing uses a specific marker usually called .stfolder to determine
355 whether a folder is healthy. This is a safety check to ensure that your
356 folder is properly readable and present on disk. For example, if you
357 remove a USB drive from your computer or unmount a filesystem, then
358 syncthing must know whether you have really deleted all of your files.
359 Therefore, syncthing always checks that the .stfolder is present.
360 When this error appears, syncthing assumes that the folder has encoun‐
362 tered some type of error and will stop syncing it until the .stfolder
363 reappears. Once that happens, all changes made to the folder locally
364 will be synced (i.e. missing files will be considered deletions).
365 • If you get this error message, check the folder in question on your
367 storage. If you have unmounted the folder (or a parent of it), you
368 must remount it for syncthing to resume syncing this folder.
369 • If you have moved the folder, you must either move it back to its
371 original location, or remove the folder from within the syncthing UI
372 and re-add it at its new location.
373 • If the folder is present on disk, with all of its children files and
375 directories, but the .stfolder is still missing:
376 It is possible that a file cleaning software has removed the
378 .stfolder. Some software removes empty folders, and the .stfolder is
379 often empty. This happens particularly often on Android. To remedi‐
380 ate, recreate the .stfolder and add a dummy file in it, or add an ex‐
381 ception to your cleaning software.
382 If you are still unsure what has happened, you can remove the folder
384 from within the syncthing UI and re-add it at the same location. This
385 causes syncthing to attempt an automatic re-creation of the .stfolder.
386 Next, it will also reset the database state of this folder. It will be
387 considered a “new” folder, meaning that its files will be merged with
388 files from remote devices.
389 Also see the marker FAQ for more information about the folder marker.
391
393 What if there is a conflict?
394 SEE ALSO:
395 Conflicting Changes
396 How do I serve a folder from a read only filesystem?
398 Syncthing requires a “folder marker” to indicate that the folder is
399 present and healthy. By default this is a directory called .stfolder
400 that is created by Syncthing when the folder is added. If this folder
401 can’t be created (you are serving files from a CD or something) you can
402 instead set the advanced config Marker Name to the name of some file or
403 folder that you know will always exist in the folder.
404 I really hate the .stfolder directory, can I remove it?
406 See the previous question.
407 Am I able to nest shared folders in Syncthing?
409 Sharing a folder that is within an already shared folder is possible,
410 but it has its caveats. What you must absolutely avoid are circular
411 shares. This is just one example, there may be other undesired effects.
412 Nesting shared folders is not supported, recommended or coded for, but
413 it can be done successfully when you know what you’re doing - you have
414 been warned.
415 How do I rename/move a synced folder?
417 Syncthing doesn’t have a direct way to do this, as it’s potentially
418 dangerous to do so if you’re not careful - it may result in data loss
419 if something goes wrong during the move and is synchronized to your
420 other devices.
421 The easy way to rename or move a synced folder on the local system is
423 to remove the folder in the Syncthing UI, move it on disk, then re-add
424 it using the new path.
425 It’s important to do this when the folder is already in sync between
427 your devices, as it is otherwise unpredictable which changes will “win”
428 after the move. Changes made on other devices may be overwritten, or
429 changes made locally may be overwritten by those on other devices.
430 An alternative way is to shut down Syncthing, move the folder on disk
432 (including the .stfolder marker), edit the path directly in config.xml
433 in the configuration folder (see Syncthing Configuration) and then
434 start Syncthing again.
435 How do I configure multiple users on a single machine?
437 Each user should run their own Syncthing instance. Be aware that you
438 might need to configure listening ports such that they do not overlap
439 (see Syncthing Configuration).
440 Does Syncthing support syncing between folders on the same system?
442 No. Syncthing is not designed to sync locally and the overhead involved
443 in doing so using Syncthing’s method would be wasteful. There are bet‐
444 ter programs to achieve this such as rsync <https://rsync.samba.org/>
445 or Unison <https://www.cis.upenn.edu/~bcpierce/unison>.
446 When I do have two distinct Syncthing-managed folders on two hosts, how
448 does Syncthing handle moving files between them?
449 Syncthing does not specially handle this case, and most files will most
450 likely get re-downloaded.
451 In detail, the behavior depends on the scan order. If you have folders
453 A and B, and move files from A to B, if A gets scanned first, it will
454 announce the removal of the files to others who will then remove the
455 files. As you rescan B, B will announce the addition of new files, and
456 other peers will have nowhere to get them from apart from re-download‐
457 ing them.
458 If B gets rescanned first, B will announce additions first, and remote
460 peers will then reconstruct the files (not rename, more like copying
461 block by block) from A, and then as A gets rescanned, it will remove
462 the files from A.
463 A workaround would be to copy first from A to B, rescan B, wait for B
465 to copy the files on the remote side, and then delete from A.
466 Can I help initial sync by copying files manually?
468 If you have a large folder that you want to keep in sync over a
469 not-so-fast network, and you have the possibility to move all files to
470 the remote device in a faster manner, here is a procedure to follow:
471 • Create the folder on the local device, but don’t share it with the
473 remote device yet.
474 • Copy the files from the local device to the remote device using regu‐
476 lar file copy. If this takes a long time (perhaps requiring travel‐
477 ling there physically), it may be a good idea to make sure that the
478 files on the local device are not updated while you are doing this.
479 • Create the folder on the remote device, and copy the Folder ID from
481 the folder on the local device, as we want the folders to be consid‐
482 ered the same. Then wait until scanning the folder is done.
483 • Now share the folder with the other device, on both sides. Syncthing
485 will exchange file information, updating the database, but existing
486 files will not be transferred. This may still take a while initially,
487 be patient and wait until it settled.
488 Is Syncthing my ideal backup application?
490 No. Syncthing is not a great backup application because all changes to
491 your files (modifications, deletions, etc.) will be propagated to all
492 your devices. You can enable versioning, but we encourage you to use
493 other tools to keep your data safe from your (or our) mistakes.
494 How can I exclude files with brackets ([]) in the name?
496 The patterns in .stignore are glob patterns, where brackets are used to
497 denote character ranges. That is, the pattern q[abc]x will match the
498 files qax, qbx and qcx.
499 To match an actual file called q[abc]x the pattern needs to “escape”
501 the brackets, like so: q\[abc\]x.
502 On Windows, escaping special characters is not supported as the \ char‐
504 acter is used as a path separator.
505 How do I access the web GUI from another computer?
507 The default listening address is 127.0.0.1:8384, so you can only access
508 the GUI from the same machine. This is for security reasons. To ac‐
509 cess it from another computer, change the GUI listen address option in
510 the web GUI from 127.0.0.1:8384 to 0.0.0.0:8384, or change the con‐
511 fig.xml:
512 <gui enabled="true" tls="false">
514 <address>127.0.0.1:8384</address>
515 to
517 <gui enabled="true" tls="true">
519 <address>0.0.0.0:8384</address>
520 Then the GUI is accessible from everywhere. There is no filtering
522 based on e.g. source address (use a firewall for that). You should set
523 a password and enable HTTPS with this configuration. You can do this
524 from inside the GUI.
525 If both your computers are Unix-like (Linux, Mac, etc.) you can also
527 leave the GUI settings at default and use an SSH port forward to access
528 it. For example,
529 $ ssh -L 9090:127.0.0.1:8384 user@othercomputer.example.com
531 will log you into othercomputer.example.com, and present the remote
533 Syncthing GUI on http://localhost:9090 on your local computer.
534 If you only want to access the remote GUI and don’t want the terminal
536 session, use this example:
537 $ ssh -N -L 9090:127.0.0.1:8384 user@othercomputer.example.com
539 If only your remote computer is Unix-like, you can still access it with
541 SSH from Windows. Under Windows 10 or later you can use the same ssh
542 command if you install the OpenSSH Client <https://learn.micro‐
543 soft.com/windows-server/administration/openssh/openssh_install_firs‐
544 tuse>.
545 I don’t like the GUI or the theme. Can it be changed?
547 You can change the theme in the settings. Syncthing ships with other
548 themes than the default.
549 If you want a custom theme or a completely different GUI, you can add
551 your own. By default, Syncthing will look for a directory gui inside
552 the Syncthing home folder. To change the directory to look for themes,
553 you need to set the STGUIASSETS environment variable. To get the con‐
554 crete directory, run syncthing with the --paths parameter. It will
555 print all the relevant paths, including the “GUI override directory”.
556 To add e.g. a red theme, you can create the file red/as‐
558 sets/css/theme.css inside the GUI override directory to override the
559 default CSS styles.
560 To create a whole new GUI, you should checkout the files at
562 https://github.com/syncthing/syncthing/tree/main/gui/default to get an
563 idea how to do that.
564 How do I upgrade Syncthing?
566 If you use a package manager such as Debian’s apt-get, you should up‐
567 grade using the package manager. If you use the binary packages linked
568 from Syncthing.net, you can use Syncthing’s built-in automatic upgrade
569 functionality.
570 • If automatic upgrades is enabled (which is the default), Syncthing
572 will upgrade itself automatically within 24 hours of a new release.
573 • The upgrade button appears in the web GUI when a new version has been
575 released. Pressing it will perform an upgrade.
576 • To force an upgrade from the command line, run syncthing --upgrade.
578 Note that your system should have CA certificates installed which al‐
580 lows a secure connection to GitHub (e.g. FreeBSD requires sudo pkg in‐
581 stall ca_root_nss). If curl or wget works with normal HTTPS sites, then
582 so should Syncthing.
583 Where do I find the latest release?
585 We release new versions through GitHub. The latest release is always
586 found on the release page <https://github.com/syncthing/syncthing/re‐
587 leases/latest>. Unfortunately GitHub does not provide a single URL to
588 automatically download the latest version. We suggest to use the GitHub
589 API <https://api.github.com/repos/syncthing/syncthing/releases/latest>
590 and parsing the JSON response.
591 How do I run Syncthing as a daemon process on Linux?
593 If you’re using systemd, runit, or upstart, we ship example configura‐
594 tions <https://github.com/syncthing/syncthing/tree/main/etc>.
595 If however you’re not using one of these tools, you have a couple of
597 options. If your system has a tool called start-stop-daemon installed
598 (that’s the name of the command, not the package), look into the local
599 documentation for that, it will almost certainly cover 100% of what you
600 want to do. If you don’t have start-stop-daemon, there are a bunch of
601 other software packages you could use to do this. The most well known
602 is called daemontools, and can be found in the standard package reposi‐
603 tories for almost every modern Linux distribution. Other popular tools
604 with similar functionality include S6 and the aforementioned runit.
605 How do I increase the inotify limit to get my filesystem watcher to work?
607 You are probably reading this because you encountered the following er‐
608 ror with the filesystem watcher on linux:
609 Failed to start filesystem watcher for folder yourLabel (yourID):
610 failed to setup inotify handler. Please increase inotify limits, see
611 https://docs.syncthing.net/users/faq.html#inotify-limits
612 Linux typically restricts the amount of watches per user (usually
614 8192). When you have more directories you need to adjust that number.
615 On many Linux distributions you can run the following to fix it:
617 echo "fs.inotify.max_user_watches=204800" | sudo tee -a /etc/sysctl.conf
619 On Arch Linux and potentially others it is preferred to write this line
621 into a separate file, i.e. you should run:
622 echo "fs.inotify.max_user_watches=204800" | sudo tee -a /etc/sysctl.d/90-override.conf
624 This only takes effect after a reboot. To adjust the limit immediately,
626 run:
627 echo 204800 | sudo tee /proc/sys/fs/inotify/max_user_watches
629 How do I reset the GUI password?
631 If you’ve forgotten / lost the GUI password, you can reset it using the
632 --gui-password (and possibly --gui-user) options to the syncthing gen‐
633 erate subcommand. This should be done while Syncthing is not running.
634 1. Stop Syncthing: syncthing cli operations shutdown
636 2. syncthing generate --gui-password=myNewPassword --gui-user=newUser‐
638 Name
639 3. Restart Syncthing as usual.
641 Alternatively, in step 2, you can manually delete the <user> and
643 <password> XML tags from the <gui> block in file config.xml. The loca‐
644 tion of the file depends on the OS and is described in the
645 configuration documentation.
646 For example, the two emphasized lines below would be removed from the
648 file.
649 <gui enabled="true" tls="false" debugging="false">
651 <address>127.0.0.1:8384</address>
652 <user>syncguy</user>
653 <password>$2a$10$s9wWHOQe...Cq7GPye69</password>
654 <apikey>9RCKohqCAyrj5RjpyZdR2wXmQ9PyQFeN</apikey>
655 <theme>default</theme>
656 </gui>
657
659 The Syncthing Authors
660
662 2014-2019, The Syncthing Authors
663v1.25.0 Oct 05, 2023 SYNCTHING-FAQ(7)