Error "create multi-volume snapshots of instance i-123456789 failed" may occur during backup

Error "create multi-volume snapshots of instance i-123456789 failed" may occur during backup

Error:

You might see this error in the cpm server logs or the UI Alerts when running backups in CPM 3.0 and above: 
create multi-volume snapshots of instance i-123456789 failed. Error: You are not authorized to perform this operation. Encoded authorization failure message: abc-IbEpyyS9hdEilkj-GR1Zsv8O3Atm7TTAwqDrTUbOemMBTrKV1ut59JVZJUfNatIn70zRFyoRvg.....(UnauthorizedOperation)  

Solution

In version 3.x we are using a new API to take snapshots and the most common issue for the above error is the lack of permissions.
You need to make sure that you have used the latest JSON template attached to our Kb article:
  1. What are the required minimal AWS permissions/roles for CPM operation?
You can also have a look at this KB Article which shows how to check for permissions: N2WS 3.0.0 How to Check for AWS Permissions

As suggested in the article, you can use the AWS https://policysim.aws.amazon.com/ to test the permissions,
Check that the CPM role is allowed for these two permissions: ec2:CreateSnapshots and ec2:CreateSnapshot


If the problem still persists, then another option is to decode the encoded message in the error (Encoded authorization failure message:)
You can use the following AWS CLI command to decode the encoded message (which originate from AWS)
  1.  aws sts decode-authorization-message --encoded-message <encoded message>