Duplicati very unreliable on macOS High Sierra

At the beginning of July, I noticed by pure chance that the Duplicati process had not been backing up anything since June 22nd. Restarting Duplicati.app fails since then. Killing the mono-sgen processes (there are usually two of them) does not help. Right now I use the hack of calling the executable inside Duplicati.app via the shell. The log output from June 22nd does not reveal any critical error that would explain the hanging process.

Jul 4, 2018 10:22 PM: Message
removing file listed as Temporary: duplicati-20180623T225528Z.dlist.zip.aes
Jun 22, 2018 11:13 PM: Message
Expected there to be a temporary fileset for synthetic filelist (53, duplicati-b06e35bdf19ba4d5d8ab178af8481f65f.dblock.zip.aes), but none was found?
Jun 22, 2018 11:13 PM: Message
scheduling missing file for deletion, currently listed as Uploading: duplicati-i37ce2e5f6d4443449ca5cc05534a0a11.dindex.zip.aes
Jun 22, 2018 11:13 PM: Message
scheduling missing file for deletion, currently listed as Uploading: duplicati-b81f9df6b7e1d4b949600a6987ca17537.dblock.zip.aes

Today I started the exe once again and got an error message saying that the database is blocked. Again I killed all mono-sgen processes. Starting the executable again (still over command line, running Duplicati.app still fails silently) produced no more error messages in the UI; however, I cannot find any trace of the database error in the log output.

I have no idea how to troubleshoot this and make Duplicati stable and reliable on my MacBook. Any hints about where to start?

The log lines you provided are indeed standard items and don’t indicate anything wrong.

The reason you can’t find the database error in the log output is that for anything other than catastrophic failures to even start, Duplicati stores the log information IN the database. Since the database was locked, it couldn’t write the log information TO the database.

What version of Duplicati are you using and is it running OK now (meaning we’re trying to figure out how to avoid future cases of your July 22nd stoppage)?

Thank you @JonMikelV for explaining the details, the symptoms make much more sense now.

I am using Duplicati The link “Check for updates now” does nothing – not sure if I have the latest beta or if the link is not working. The downloads page also says, so I guess I am not behind.

Right now Duplicati runs OK. I had to install an OS update and therefore reboot the system; since then Duplicati is running without the shell hack. The menu bar icon was missing but killing the Python process restored the icon without problems.

However, there is still some uncertainty lingering in the back of my head. I expect that the next time Duplicati crashes I will have to use the shell hack again to continue running Duplicati without rebooting the system. And the next silent hang might as easily escape my attention as the previous one did.

Yes, is the most recent beta version.

And while it’s nice that Duplicati doesn’t need anything installed anywhere other than the source machine it did mean if it crashes you may not be notified about it.

There are a few notification solutions, all third party tools, one of which is Announcing dupReport - A Duplicati Email Report Summary Generator.