Active IQ Unified Managerのリストア後、日次バックアップとフルバックアップが次のエラーで失敗します。「Access denied for user 'jboss'@'localhost'」

環境

Active IQ Unified Manager 9.7以降（RHEL / CentOS）

問題

Unified Managerの新規インストールにバックアップをリストアしたあと、毎日のスケジュールされたバックアップとフルバックアップが次のエラーで失敗します。

2021-01-20 22:00:02,726 ERROR [oncommand] [taskScheduler-1] [Backup|ScheduleBackup] [c.n.d.i.b.MySqlDumpBackupManager] Error occured while taking mysql dump. Error message:
2021-01-20 22:00:02,726 ERROR [oncommand] [taskScheduler-1] [Backup|ScheduleBackup] [c.n.d.i.b.MySqlDumpBackupManager] mysqldump: Got error: 1045: Access denied for user 'jboss'@'localhost' (using password: NO) when trying to connect
2021-01-20 22:00:02,731 INFO [oncommand] [taskScheduler-1] [Backup|ScheduleBackup] [c.n.d.i.b.MySqlDumpBackupManager] Deleted BackupFileInfo entity in DB
2021-01-20 22:00:04,373 ERROR [oncommand] [taskScheduler-1] [Backup|ScheduleBackup] [c.n.d.impl.backup.BackupScheduleJob] Error occurred in Regular Backup Job: