AWS Backup- EC2- Backup job expired before completion.

On a general note, the error “Backup job expired before completion” occurs when the backup of the instance is not completed within the backup window. You have an option to define the backup window “Completed within” in the backup rule configuration.

“Complete within” value defines the period of time during which your backup must complete. If the data transfer for backing up your resource does not complete during this period of time, AWS Backup will display the status Expired. Otherwise, the data transfer portion of your backup job completed successfully.

Backup of an instance is dependent on various factors including but not limited to the size of the volumes attached to the instance:

() Last Snapshot - Since the snapshots of EC2 instances are incremental in nature, the more the changes since the previous snapshot the more time will be taken to finish the backup. () I/O Operations - If the number of I/O operations are high during the time the instance is being backed up, then it will take longer for the instance to be backed up.

Additionally, since there is no SLA for the time taken to backup an EC2 instance, it is not possible to predict how much time it will take for the backup to finish as there are many variables that might come into play during the backup which is the reason why the backup fails sometimes.

I advise you to verify the time value defined at the “completed within” in your backup configuration. To resolve / avoid this error, I advise you to increase the backup window by navigating through the below path:

AWS Backup -> Backup plans -> [Bakcup plan NAME] -> SELECT [BACKUP RULE] -> click on “Edit” -> Choose “Customize backup window” -> “Complete within”

References: => https://docs.aws.amazon.com/aws-backup/latest/devguide/creating-a-backup-plan.html?icmpid=docs_console_unmapped#backup-rules => https://docs.aws.amazon.com/aws-backup/latest/devguide/updating-a-backup-plan.html