Excellent work, many thanks @acolomb & @hgy59 and, needless to say, thanks to all involved in Syncthing for providing and supporting such an amazing piece of software 
5 Likes
I manage two NAS devices, both on DSM 7.x. I reported that I hit the issue when installing v1.19.0-24 on the first. I can now report that installing v.1.19.0-25 did not cause the same issue.
Thanks @calmh for helping to engage the right folks and thanks @acolomb and @hgy59 for the fix!
2 Likes
I updated 1.19.0-25 and now the service will not run, how did you resolve?
This is a known problem with a fix already pending for the next package update. It just hasnāt been published yet. The simplest solution to quickly fix the problem of not starting is shared in another thread:
Note there is some advice on other possible solutions in there as well. But all you really need is the one command from the linked post, entered through an SSH session as admin.
Tracking the issue happens at Syncthing Not Starting, after update to 1.19.0.25 Ā· Issue #5142 Ā· SynoCommunity/spksrc Ā· GitHub.
Hmm. I think it happend again to me. Two of my DSM6 syncthings stopped working after upgrading synthing in the synology package center to v1.20.0-26. It is running, but i cannot open the gui. DSM7 is still running. Am I the only one with this problem?
Thatās interesting, can you try to provide more details? Log file would help for example, it should be acccessible through the standard Log Center application on DSM or under /var/packages/syncthing/var/syncthing.log.
I just tried the upgrade right now on my box running DSM 6.2.4 and it worked without any problem.
Hi, here is the log. I removed the idās. Thanks in advance.
Sun May 8 12:52:18 CEST 2022
Begin service_prestart
End service_prestart
Starting syncthing command /volume1/@appstore/syncthing/bin/syncthing serve --home=/volume1/@appstore/syncthing/var
[start] 2022/05/08 12:52:18 INFO: syncthing v1.20.1 "Fermium Flea" (go1.18.1 linux-arm) teamcity@build.syncthing.net 2022-05-04 16:17:03 UTC
Sun May 8 12:52:18 CEST 2022 Begin service_prestart
End service_prestart Starting syncthing command /volume1/@appstore/syncthing/bin/syncthing serve --home=/volume1/@appstore/syncthing/var
[start] 2022/05/08 12:52:18 INFO: syncthing v1.20.1 "Fermium Flea" (go1.18.1 linux-arm) teamcity@build.syncthing.net 2022-05-04 16:17:03 UTC
[IPRBJ] 2022/05/08 12:52:20 INFO: My ID: IremovedTheID
[IPRBJ] 2022/05/08 12:52:21 INFO: Single thread SHA256 performance is 4.4 MB/s using minio/sha256-simd (4.4 MB/s using crypto/sha256).
[IPRBJ] 2022/05/08 12:52:23 INFO: Hashing performance is 3.69 MB/s [IPRBJ] 2022/05/08 12:52:23 INFO: Overall send rate is unlimited, receive rate is unlimited [IPRBJ] 2022/05/08 12:52:23 INFO: Using discovery mechanism: IPv4 local broadcast discovery on port 21027 [IPRBJ] 2022/05/08 12:52:23 INFO: Using discovery mechanism: IPv6 local multicast discovery on address [ff12::8384]:21027 [IPRBJ] 2022/05/08 12:52:23 INFO: TCP listener ([::]:22000) starting [IPRBJ] 2022/05/08 12:52:23 WARNING: Listen (BEP/tcp): Accepting connection: accept tcp [::]:22000: accept: function not implemented [IPRBJ] 2022/05/08 12:52:23 INFO: GUI and API listening on [::]:8384
[IPRBJ] 2022/05/08 12:52:23 INFO: Access the GUI via the following URL: https://127.0.0.1:8384/ [IPRBJ] 2022/05/08 12:52:23 WARNING: GUI/API: accept tcp [::]:8384: accept: function not implemented (restarting)
[IPRBJ] 2022/05/08 12:52:23 INFO: My name is "NAS" [IPRBJ] 2022/05/08 12:52:23 INFO: Device IremovedTheID is "NAS2" at [dynamic] [IPRBJ] 2022/05/08 12:52:23 INFO: Device IremovedTheID is "NAS3" at [dynamic] [IPRBJ] 2022/05/08 12:52:23 INFO: Ready to synchronize "Folder" (bg36XX-ssvXy) (sendreceive) 2022/05/08 12:52:23 failed to sufficiently increase receive buffer size (was: 112 kiB, wanted: 2048 kiB, got: 224 kiB). See https://github.com/lucas-clemente/quic-go/wiki/UDP-Receive-Buffer-Size for details. [IPRBJ] 2022/05/08 12:52:23 INFO: GUI and API listening on [::]:8384
[IPRBJ] 2022/05/08 12:52:23 INFO: Access the GUI via the following URL: https://127.0.0.1:8384/ [IPRBJ] 2022/05/08 12:52:23 WARNING: GUI/API: accept tcp [::]:8384: accept: function not implemented (restarting)
The last warning is interessting. SC seems to run but something with the gui is broken.
Best regards Matthias
This is "accept: function not implemented" after upgrading to syncthing v1.20.1 Ā· Issue #8325 Ā· syncthing/syncthing Ā· GitHub, in short your kernel is too old.
Ok. So my only option is to go back to the last running version and disable the updates for syncthing, right?
If you canāt upgrade the system to something newer, yes, I think so.
Which Synology DS types you are using?
Two DS413j and one DS415play
DS413j has platform āMarvell Kirkwood 88F6282ā // 88f628x
DS415play has platform Intel Atom CE5335 // Evansport
So, formal both are supported.
Maybe the list of supported devices needs an updateš
I donāt think so, actually.
I assume that the two DS413j are the ones whose GUI does not respond. Maybe itās just a matter of waiting, because these have a DDR3 with 512 MB, which isnāt much, plus a ājā isnāt necessarily performant either. How much data do you have and how big are the biggest files?
What about the DS415play, does it work with the update?
I have also updated a DS415+ which is similar to the DS415play and it runs without problems.
The 415play is running fine.
The 413j are not responding on the gui. Yes the are old. Syncing around 10 TB, largest files ~15GB.
Andy, read above. At least some devices with at least some versions of DSM 6 have a kernel thatās too old to run the latest Syncthing builds. Itās not a question of whether these devices are āsupportedā by SynoCommunity or by Syncthing. Though, if they can be upgraded to DSM 7 that maybe comes with a newer kernel. 
The culprit is in the following commit, isnāt it?
If one reverts the commit (e.g. by modifying the files in the local Goās src folder), and then compiles Syncthing themselves, everything should still work as before, right?
Probably rather the mentioned CL, as that looks like just a cleanup commit. But honestly, I donāt really care to figure it out or try it to answer that question. Go for it, if you like.
At some point, if youāre going to run a decade-plus old operating system you have to accept that thereās a horizon for how new software you can run. Running a one month old Syncthing on that operating system seems part and parcel of the trade-off.
Anyway ā¦ good to know, finally it seems no Syncthing issue. In addition Synology is known to use rather older kernels, because the DSx15 are not much older either.
You probably still had the SynoCommunity Syncthing package version 1.19.0-25 installed and had to rebuild the config, wasnāt that the case? Did you have the automatic internal update activated until the update to version 1.20.0-26?
If you now want to reinstall older version 1.19.0-25 or even 1.17.0-22, it gets a bit trickier, because then you would have to set to lower package version via console, otherwise no previous version can be installed. Otherwise only a new installation would help.