~From: [Source: Quest - Important Notification: Rapid Recovery 6.3 Product Support ]
We've recently learned about an issue that affects backups of agentlessly protected ESXi VMs to Rapid Recovery Core v.6.3. In specific cases, backups may be invalid and require specific mitigation.
This issue only affects:
If using ESXi agentless protection with SAN transport mode, backups captured since installation of/upgrade to version 6.3 may be invalid. If integrity checks are enabled, they will start failing. To diagnose, enable integrity checks.
How does this affect me?
If you are using Rapid Recovery Core version 6.3 with agentless protection of VMware with SAN transport mode, then this issue will impact you. If you are using Rapid Recovery version 6.2.1 or earlier, this issue does not apply.
We advise you to enable integrity checks to identify the issue. See User Guide - Enabling Nightly Jobs for details.
To confirm which transport mode you are using check the application log. Search the log for "Actual transport mode". You will find lines like these below, showing the transport mode in use:
DEBUG 2015-04-18T08:42:59  - Replay.Core.Implementation.VSphere.DiskVolumes.EsxVirtualDiskReaderWriter (DetermineDataToSendTask AgentDisplayName=8.1 VolumeName=\\Hard disk 2\Volume 1)
Actual transport mode for disk 'Hard disk 2' is 'nbd'
If you have not yet upgraded to Rapid Recovery v6.3 and you use SAN transport mode, please follow the upgrade steps in knowledge base article 302070 or switch to using the NBD transport mode prior to upgrade.
This issue will be addressed in the next release of Rapid Recovery.