Is live migration causing data corruption?

Theo Lassonder asked:

We have two virtual hosts (Xen 4.9) and live migrate guests between them. The storage of the guests is accessible via iSCSI. That is, a guest running on host A has its storage presented as a straight block device, and the device is mounted on host A with iscsiadm.

The guest configuration for storage is:

<disk type='block' device='disk'>
  <driver name='qemu' type='raw' cache='writethrough'/>
  <source dev='/dev/disk/by-path/'/>
  <target dev='hda' bus='ide'/>
  <address type='drive' controller='0' bus='0' target='0' unit='0'/>

When live migrating this guest to host B, is there a possibility for data corruption, and if, how should this be configured?

My answer:

As long as the shared storage is accessible to both hypervisors, you’ll have no problem with live migration.

If the destination hypervisor doesn’t have access to the shared storage, then it should refuse to accept the live migration, or if it’s in progress, abort it.

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