Avamar: Avtar Fails When Run-at-Start Script Returns Non‑Zero Exit Code

Backup failures when using a run‑at‑start script

Backups do not complete when a custom run‑at‑start script is configured for avtar.

• Avtar logs indicate it returned from the run‑at‑start script with a non‑zero exit code.
• Backup jobs are marked as failed.
• Disabling the run‑at‑start script allows the backup to succeed.

avtar Info : Back from run-at-start, exit code 1
avtar Error : Exiting avtar with run-at-start script failure 1

Improper Exit Code from Run‑at‑Start Script

The backup fails because the custom run‑at‑start script returns an exit code other than 0 . In Linux/UNIX environments, 0 is the only value that indicates success. Avtar interprets any non‑zero value as a script failure, causing the backup process to abort.

• The script returned exit code 1 , which avtar logged as an error.
• Avamar treats this non‑zero exit code as a failure and stops the backup operation.

Relevant log entry:

avtar Info : Back from run-at-start, exit code 1
avtar Error : Exiting avtar with run-at-start script failure 1

Correcting avtar run‑at‑start script failures

Step‑by‑step resolution

When a customized run‑at‑start script returns a non‑zero exit code, avtar treats the backup as failed. Follow these steps to ensure the script returns 0 on success.

• Locate the script configured for the avtar run‑at‑start phase (such as, /opt/avamar/etc/run_at_start.d/custom_script.sh ).
• Open the script in an editor and verify the logic that determines success or failure.
• At the end of the script, add or modify the exit statement so that a successful execution ends with exit 0 .
• Ensure any error paths also use appropriate non‑zero codes only when a genuine failure occurs.
• Save the changes and set executable permissions if they are not already set.

Example of a proper script termination:

#!/bin/bash
# Your custom logic here

if [ $? -eq 0 ]; then
    echo "Custom script completed successfully"
    exit 0
else
    echo "Custom script encountered an error"
    exit 1
fi

Validate the script locally

Run the script manually and confirm it exits with 0 .

$ /opt/avamar/etc/run_at_start.d/custom_script.sh
Custom script completed successfully
$ echo $?
0

Restart avtar and trigger a backup.

After confirming the script returns 0, restart the avtar service and start a backup job to verify normal operation.

# Restart avtar service
$ systemctl restart avtar

# Initiate a test backup (replace and as needed)
$ avtar -c -p -b

Confirm the resolution.

Check the avtar log for the absence of the error message "Exiting avtar with run‑at‑start script failure 1." A successful log entry resembles the following:

[2025-10-09 12:34:56] INFO avtar Info : Back from run-at-start, exit code 0
[2025-10-09 12:35:10] INFO Backup completed successfully