The incremental image fails to mount

Summary

If the backup target disk is removal type, it may fail to mount an incremental image.

– Microsoft iscsi software target
– USB HDD
– Shared disk type cluster (MSCS, MSFC)

Failure scenarios

Environment:
– Disk connected by iSCSI: X drive
– Backup Target Drive: X drive

– Node A: ActiveImage Protector installed.
– Node B: ActiveImage Protector not installed

Steps:
1) Node A: Performs basic and incremental backup.
2) Node A: Disconnect the X drive.
3) Node B: Connect X drive.
4) Node B: Update data in X drive.
5) Node B: Disconnect the X drive.
6) Node A: Connect X drive.
7) Node A: Perform incremental backup.
At this time, ActiveImage Protector updates $AIPMAP of the X drive.
However, since the machine ID is the same, will perform correctly incremental backup.

The following error occurs when you mount an incremental image that was created in step 7).

X: (allocated drive letter) cannot be accessed.
A file or directory is corrupted and unreadable.

Even if an image mount succeeds, the added or existed data is not correct data.

Cause

ActiveImage Protector creates a $AIPMAP for tracking the bitmap information. This file holds the bitmap information and machine ID.
However, the data changed by other servers can't be tracking.
Therefore, creates incremental backup from previous changes that are changed in the other server.
This inconsistency occurs in the actual data and incremental image file.

Workaround

1) Disable/enable the schedule, it will be forced to reconcile the next incremental backup.
2) Then perform a basic backup.