A backup of a Linux VM completes with the event message: "Found a multi-segment swap partition on virtual machine [vm_name]. Ensure that a new full backup has been run on this VM."

Article ID: VMW0030 For Linux virtual machines that have extended or spanned swap partitions, streaming backups or backup copies with VMware or Hyper-V might back up incorrect sectors, resulting in missing data in some volumes. This problem can occur with Version 11 in Service Packs 7, 8, and 9.

Symptom

For Linux virtual machines that have extended or spanned swap partitions, a streaming backup operation or a streaming backup copy operation with VMware or Hyper-V completes successfully, but might be missing some data.

After updates are applied for Service Pack 7, 8, or 9, the Event Viewer displays the following message for streaming backup and backup copy jobs:

Found a multi-segment swap partition on virtual machine [vm_name]. Ensure that a new full backup has been run on this VM.

If a full backup was not been perfomed after updates were applied, then the resulting backup might not include some files or folders. 

The vsbkp.log file includes the following lines:

... vsBkpDiskConfig::GetLinuxSwapPartitionSectors() - SWAP Partition has multiple [n] segments. This could either be an extended or spanned SWAP partition. Complete partition will be backed up

... VSBkpWorker::DetectPageFileSectors() - Setting property MultiSegmentedSwapPartition on vm client id = xxxx

... VSBkpWorker::DetectPageFileSectors() - Success setting property MultiSegmentedSwapPartition

Cause

By default, backups skip the page or swap file for virtual disks.

For a Linux VM that contains extended or spanned swap partitions, a backup might not be able to identify sectors correctly. As a result, the backup might have incomplete data in some volumes, making some files or folders unrecoverable.

Resolution

To resolve this issue, take the following actions:

  1. Ensure that updates are applied for the service pack. 

    If updates are not applied, then the Event Viewer does not flag VMs that contain a multi-segment swap partition.

  2. Run a new full backup for the virtual machine. 

After you run a full backup, future backups are able to capture all VM data. By default, the event message that indicates the VM contains a multi-segment swap partition is still generated, but you can ignore it.

To suppress the event message, create the bAlertOnMultiSegmentSwapPartition additional setting on the VSA proxy that is used for backups and set the value to 0.