We have recently setup Syncthing. We have 2 DELL servers (24 core/64GB Ram/640GB disk/1GB eth/plenty of disk space/Ubuntu 18.04/Syncthing 1.34 default install) in two data centers about 50mi apart. Synchronization is mostly successful.
The problem seems to be with very large files. It seems to be completely stuck when attempting to synchronize anything over about 300MiB. Of the 4 files it is stuck on, 2 are in the 400MiB range, and the other two are in the 5GiB range.
These are Virtual Machine images. Knowing they couldn’t be synchronized while running, we shut them down for a while (2 days). All other files in the folder synchronize, but those files are all much smaller. Even after 2 days of the files not changing, they still won’t sync.
We did notice a symptom. When it hits those files, it begins to rapidly go through a disconnect, reconnect cycle, which seems to exacerbate the problem. I really think it is related, but I do not know how to prove it.
If I remove this folder, then add a folder containing 90K files with a combined size of over 5GiB, it synchronizes without issue, but there are no files in the bunch much larger than a few MiB. Most are a few KiB.
We had 4 others that wouldn’t transfer, but they were very old ZIP backups we simply decided we could delete. We don’t have the same option on these, and we want to add 4 more approximately the same size.
I’m sure it can do it, but not sure what to do to make it succeed.
I did find a post suggesting we increase the scan time to a longer time. Right now it is set at the default of 1h. Any suggestions on what length of time would be required?
Also, I see some debugging options, but little idea on which ones to turn on to get meaningful output. I’ll gladly try anything with proper direction.