Synthetic full backups appear to be "hung" or stuck at 95% estimated completion


A "local" or "offsite" synthetic full backup has been running for much longer than expected, it appears to have hung.

The "local" synthetic full backup runs on the source Backup client. In this case the "hung" job can be seen on the Backup Status and Backup Sets pages: -





"Offsite" synthetic full backups run on the Offsite Server. If an offsite synthetic full backup hangs, the symptoms are: -

1) job will remain on queue with "in process = yes" status for much longer than the expected run time (check Backup Logs for the offsite server to see normal durations of offsite synthetic full backups, they vary depending on size of backup and resources in offsite server)

2) other offsite synthetic full backups may be queued behind the job that has hung, with "ready to go = yes" and "in process = no" statuses




Kaseya Backup uses Acronis command line interface (CLI) to run backup tasks, including "synthetic full" backups (which actually involves exporting a previous backup set into a new "full" backup image).

The Acronis v11.x CLI does not currently support a "silent mode" switch for the command used for "synthetic full" backups. This means that, in some circumstances, Acronis will issue a user prompt if it can't complete the task. Examples include: -

1) image location or offsite storage location disk is full

2) network connectivity to image location / offsite storage location is lost during synthetic full backup

The job will appear to be hung because Acronis is waiting for user response. This problem does not affect other types of backup, because usually Acronis tasks run in silent mode, meaning the job will fail if it can't complete without user interaction.



Please proceed as follows to diagnose individual cases where a synthetic full backup appears to be hung: -

1) retrieve the Acronis log from the agent machine. This is located in the agent working directory (by default, c:\kworking): -

- volBackupLog.XML (on Backup client)

- syntheticFullLog.XML (on Offsite Server)

2) open the XML file with a text editor (it may open in a browser by default, and display no data because XML formatting is incomplete)

3) check if there is current activity (meaning job is still active). If not, review the last few lines and check if user prompt has been issued, like in the example below


4) if job is indeed pending user prompt, it may be answered from Acronis Management Console on the Backup client or Offsite server. Retry may be used if the condition that required attention has now been corrected. If Acronis Management Console is not installed, or remote access to the client machine is not possible, the only way to end the job would be to stop the acrocmd.exe process using KLC Task Manager. Kaseya will log the synthetic full backup as failed within the next few minutes.



If any individual case cannot be resolved using the above steps, please submit the following information to Kaseya support: -

1) Acronis Info tool output from affected machine -

2) Acronis XML log from "hung" job (as described in steps 1-3 above

3) screenshots of any errors or user prompts found in Acronis Management console

4) details of any addtional troubleshooting steps taken so far

5) access to Kaseya server and names of affected machines



Kaseya Backup (v6.5 and above)

Acronis v11.x

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