Disk backup failing

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Disk backup failing

USL Azure 0

Hey, Hoping to get some help with a backup check failing. It is a disk backup, every time I check it is showing the disks as properly mounted. Can't seem to get past this error. Any help is appreciated.

Linux VM

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Answer 1

Siva shunmugam Nadessin 575 Microsoft External Staff Moderator

Hello USL Azure,

Kindly try the below steps to troubleshoot the issue:

Check Disk Status: Ensure that the disks you're trying to back up are mounted correctly in your Linux VM. You can use the df -h command to check mounted disks and their space.
Inspect Backup Status: Review the backup job logs for any specific error codes or messages. These logs often contain vital information that can help pinpoint the issue.
I/O Latency: Sometimes, high input/output latency can cause backup operations to fail. Ensure that the disks do not have high I/O latency that could affect the backup process. You might want to check the performance metrics of your Azure disks.
Connectivity Issues: If your backup relies on network shares (like SMB), ensure that there are no connectivity issues. Verify that the server service is running and responsive.
Backup Agent: Ensure that the Azure Backup agent is installed correctly on your Linux VM and that it is up to date.
Re-run Full Backup: If there are corrupt backup files, you might need to force a full backup after resolving any underlying issues. If no valid backup set exists, the restore job may fail.

Here are some resources that might help:

Please click Accept Answer and upvote if the above was helpful.

Thanks,

Siva shunmugam.

USL Azure 0 Reputation points

2025-08-25T23:00:09.3866667+00:00

Hey Siva,

Thank you for the information.

I did test all of the above.

There doesn't seem to be any connectivity issue, Latency seems to be performing well.

I did check disks, see screenshot below.

I can't see anything that would be marking the drives as inaccessible. They are set to Read/Write disks in the Azure Portal.

Backup agent is on version 2.14.0.1 and is showing as "Ready".
Siva shunmugam Nadessin 575 Reputation points Microsoft External Staff Moderator

2025-08-26T00:28:54.3866667+00:00
Hello USL Azure,

Kindly check the below troubleshooting steps and see if it helps

Backup Job Logs: Revisit the backup job logs one more time. Look specifically for timestamps that can help locate where the process fails. Error codes in the logs can often provide clues to the root cause.

Disk Space: Ensure that there’s enough space available on the disks being used for backup. Low disk space can sometimes lead to failed backup operations.

Permissions: Verify that the Azure Backup service has the necessary permissions to access the disks. Sometimes, issues in permissions can prevent the backup process from completing successfully.

Backup Policy: Review the backup policy settings to ensure that there are no issues that might be preventing the successful backup of your disks.

Agent Logs: Check the Azure Backup agent logs on your Linux VM for any error messages or warnings that might give you a better idea of what’s going wrong.

Retry a Full Backup: As a last resort, after all relevant issues have been resolved, try to re-run a full backup. Sometimes, previous failures can affect subsequent jobs until a full backup is successfully completed.

Please click Accept Answer and upvote if the above was helpful.

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Disk backup failing

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