Ignore bad sectors feature

Details

When setting up the backup schedule, go to [2 Destination] → [Advanced Settings] → [General] and enable Ignore bad sectors.
Note: The location of this option may vary depending on the AIP version.

When enabled, bad sectors on the backup source will not stop the backup, and no error will be returned.

This option is useful if a hard disk is aging. You can still create a backup by enabling this setting, then restore the data to a new replacement disk.

AIP Online Backup temporarily creates snapshots on the local disk and transfers the backup data to the destination. Due to snapshot driver limitations, snapshots may be deleted or exceed preset limits. 

Regarding snapshot behavior during the backup process:

Windows Edition
Backups use VSS snapshots to transfer data. VSS snapshots use space from the volume’s shadow storage (typically about 10%). As I/O activity occurs on the source volume in backup process, the snapshot size grows. If the snapshot exceeds the available shadow storage space, some snapshots may be deleted automatically.

In this case, a message like the following is recorded in the Windows Event Log.

- Volume X: did not have enough disk space for the enlarged storage area of shadow copy of Volume X. As a result, the shadow copy of Volume X may be entirely deleted.
- The shadow copy for Volume X: is stopped because the shadow copy storage could not be expanded.

Linux Edition
Backups use Datto snapshots to transfer data. Datto snapshots reserve 10% (threshold) of each backup source volume as snapshot space. During the backup, I/O activity increases the snapshot size. If the snapshot exceeds this predefined limit, the backup fails with an error.

In this case, the following message is logged in the Linux system log. 

May 7 11:43:59 rhel94efit01 kernel: datto: cow file '/.datto' max size exceeded (5372485632/5372483993): -27
May 7 11:43:59 rhel94efit01 kernel: datto: error writing cow data: -27
May 7 11:43:59 rhel94efit01 kernel: datto: error writing cow data and mapping: -27
May 7 11:43:59 rhel94efit01 kernel: datto: memory demands 1291845632, memory saved before crash 102400: -27
May 7 11:43:59 rhel94efit01 kernel: datto: error handling write bio: -27
May 7 11:43:59 rhel94efit01 kernel: datto: error handling write bio in kernel thread: -27
May 7 11:43:59 rhel94efit01 kernel: Buffer I/O error on dev datto1, logical block 1024, async page read

Snapshots are actual files. Because it’s difficult to tell the difference between bad sectors and snapshot data corruption, some processes may appear to complete successfully even if a snapshot is deleted or exceeds its limit.

In these cases, backup files may be missing data from the affected sectors, resulting in image files with significant data corruption.

For this reason, using Ignore bad sectors together with online snapshots is not recommended.

In earlier versions, Ignore bad sectors was enabled by default. To prevent this issue, it is disabled by default starting with AIP 2022.

Windows Edition
The applicable version is 7.0.3.8919.
Patch Version 24.4.18.1 (April 18, 2024)

Once the patch is applied, the version becomes: 
Agent Version : 7.0.4.9021
Console Version :7.0.4.9021

Linux Edition
Version 7.0.4.9023（April 18, 2024）

Target Product

- ActiveImage Protector

(53596138212121)