Large Files not Synching

[Nummer378 (Max)]

It looks to me like the core issue here is version confusion, so maybe the following will make things a bit clearer:

• Syncthing v1.4.0 is the most recent version, at the time of writing.

If you installed syncthing with the Debian/Ubuntu package manager apt (or apt-get), there are two mirrors which both host different syncthing versions.

1. The official Ubuntu repository, which is present by default. You say you’re running Ubuntu 18.04. This Ubuntu version distributes syncthing 0.14.43+ds1-6. This is a custom build, made by the Ubuntu packagers, and is based on syncthing v0.14.43. Note the leading zero here, which is important.
2. An inofficial repository, hosted by the syncthing project, that always contains the latest version (again, that is 1.4.0). This repository is available under apt.syncthing.net.

Version v0.14.43 is over two years old and is incompatible with newer versions (see the announcement below). Since then, syncthing has made the “1.0” milestone, which is why newer versions have a leading “1”, not a “0”.

Syncthing versions prior to 0.14.46 are bad.

If you’re using a release prior to 0.14.46 (released April 4, 2018) you need to upgrade. Especially if you are here to let us know that it crashes. Specifically, those old versions have problems with large / variable blocks which are default in 1.1.0+ and mandatory in 1.2.0+ (coming soon). You cannot have a cluster with some devices at 1.2.0 and newer and some other devices on 0.14.45 or older. You need to either get with the newer program, or remain on the older. For most user…

It looks like you have one device running v1.4.0 and one device v0.14.43. The latter device has installed the version from the Ubuntu repository, which is why it’s so outdated. You need to add the syncthing repository to that device, then upgrade it normally (apt update & apt upgrade). You have already done this on the other device, but apparently not on both.