Backup job using Comet Backup is failing wih Io error: encrypted object metadata is incomplete

Symptoms

A backup job fails or ends with errors after trying to sync with the target Storage Vault. The job log displays an error message similar to:

CONFIG_TEXT: Retried 1 times over 39:36:35: List<resource path>: Io error: encrypted object metadata is incomplete

Cause

This error indicates data corruption within the index files (packindex) stored in your target Storage Vault.

Comet Backup relies on these index files to map out which chunks of encrypted data belong to which files. The phrase encrypted object metadata is incomplete means that when Comet attempted to read or decrypt the remote index metadata, it found a file that was missing expected bytes, was truncated, or was entirely zero-byte.

The index files can also be left truncated by a temporary issue on the storage provider side, for example a failed or truncated read response from the storage backend.

Resolution

To resolve this, you need to clear out the corrupted index cache and force Comet to rebuild the index from the actual data chunks. You can trigger a rebuild of the Storage Vault indexes directly from the Comet Management Console. After a successful reindex, perform a retention pass before running another backup job.

1. Log in to your Comet Management Console and toggle on Advanced Options in Admin menu.

   
   
    

2. Go to Users > select the user > open the Devices tab > Actions....

3. In the opened window, switch to Storage Vaults tab and click Reindex.

   
   
    

4. Open the same Storage Vault tab again and click Apply Retention Rules Now.

   
   
    

5. When the retention pass is done, go to Users > select the user > switch to the Job Logs tab > open the Report of the last job. You should see a successful reindex and cleanup.

   Note: If reindex or retention pass ended up with error, submit the job log report to Comet Backup Support Team. If both are successful, proceed to step 6.

6. Run a backup job to confirm.