Hi Youqin,
What was the procedure followed to clone A to B?
Was the original SIA on B recreated on new DB?
And changed the clustername as well?
Have a look at: 1275068 - Backup and restore of filestore and CMS database of a BusinessObjects Enterprise XI 3.x/BI 4.0/BI 4.1 system
This is the complete process to restore an environment from a backup.
-Sid