Starting Backup Failed revisited

I’m using the current @uroni “uroni-urbackup-server:latest” Docker container (UrBackup 2.3.8). and had performed a successful full file backup of a new client, however, six hours later the urbackup web console listed the client as having a file backup status of “No recent backup”. Also, the backups are now failing with the message ‘Starting Backup Failed’. Debug has been enabled on the client / server and I’m not seeing any evidence of an issue in the logs.

More info - the urbackup clients (when initially installed) seem to use autodiscover to locate the urbackup server, however, the clients become disconnected from the server after a period of time. The evidence is that the client’s “online” status in the urbackup web onsole switches to “No” when the client is in fact online. Also, the “IP” in the urbackup web console goes from the actual IP to a hyphen which would seem to indicate that the server no longer knows who the clients are. It’s at this stage that the backups start to fail. My urbackup server docker container sits on a different subnet from the clients and I suspect this is where the problem is emanating from. At this point I have a few options to pursue in accordance with chapter 5 and 7 of the UrBackup manual. First, ensure the urbackup server container can resolve the host names of the clients (I’m fixing / testing this now). If this doesn’t fix the issue with clients going offline, then look at either placing the urbackup server container on the same subnet as the clients or switch the clients to internet mode. More to come as I work through this.

Fixing the client name resolution didn’t appear to resolve the issue. What ultimately resolved this was ensuring the UrBackup server docker container was connected directly to the same subnet as the clients.

Steps to determine if UrBackup server docker container is on the same subnet as the clients.

  1. Open a terminal within the UrBackup docker container.
  2. apt-get update
  3. apt-get install traceroute
  4. traceroute (IP of client)

The output of the traceroute command should be similar to the following below and contain only one hop count.

root@uroni-urbackup-server1:/# traceroute
traceroute to (, 30 hops max, 60 byte packets

  1. (  0.983 ms  0.927 ms  0.911 ms