Is pre_backup script running parallel to the backup?

twind · August 27, 2021, 8:20am

Hey there,

i got a really weird behaviour with the client pre_backup script. I excepted the client to wait for the script to execute and finish before starting the actual backup.

But it doens’t seem like it. I use the pre_backup script for turning on and mounting my backup drive. When everything is fine and the drive is readily mounted, it returns with 0. And it worked perfectly well with bacula.

But the UrBackup client seems to start the pre_backup script in parallel to starting the backup job. Which leads to some files being written in the mount point already when the drive is not mounted yet. The rest of the files are going to the mounted device. Of course this leads to a lot of weird failures in the end.

I didn’t expect this behaviour as it makes no sense for a pre_backup script, does it?

I have no idea how to fix this issue. Any help would be greatly appreciated!

Ah by the way, the script has a timeout in it to make sure the drive is ready and mounted before it returns. So that can’t be the issue.

uroni · August 28, 2021, 11:01am

Should run synchronously:

github.com

uroni/urbackup_backend/blob/dev/urbackupclient/client.cpp#L4104

    
      
          	}
          	else if (!output.empty())
          	{
          		Server->Log("Script \"" + script_name + "\" returned with success", LL_INFO);
          		VSSLogLines(output, LL_INFO);
          	}
          
          
	return rc;
          }
          
          
int IndexThread::execute_prebackup_hook(bool incr, std::string server_token, int index_group)
          {
          	std::string script_name;
          #ifdef _WIN32
          	script_name = Server->getServerWorkingDir() + "\\prefilebackup.bat";
          
          
	if (getFile(script_name)
          		==":: Commands in this file will be executed before each incremental or full file backup")
          	{
          		return 0;
          	}