Solution for backups not encrypting
If tape backups are not encrypted, consider the following solutions:
Verify that a backup is not encrypted by checking that the encryption key tag field is not set in the image record.
Verify that the key group and volume pool names are an exact match.
Verify that there is a key record in the key group with an active state.
Other non-KMS configuration options to look at include:
Verify that everything that is related to traditional media management is configured properly.
Is the NetBackup policy drawing a tape from the correct volume pool.
Does the encryption-capable tape drive have encryption capable media available. For example is LTO4 media installed in the LTO4 tape drive?