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Ahsay Upgrade Advisory (#30181) – Critical Issue with AhsayOBM v8 Microsoft Hyper-V 2016/2019 incremental backup

We have recently confirmed a critical issue related to virtual machine backups on Hyper-V 2016/2019, due to a bug in the handling of RCT (Resilient Change Tracking) data, AhsayOBM is not able to correctly detect the block level changes on the virtual machine during an incremental backup. Even though AhsayOBM reports the backup is completed successfully, all Hyper-V 2016/2019 virtual machine incremental backups are no longer restorable.

What are the affected AhsayOBM versions?

  • AhsayOBM v8.3.6.0 to v8.5.0.127

What are the affected Hyper-V versions?

  • Hyper-V 2016 (Standalone/Cluster)
  • Hyper-V 2019 (Standalone/Cluster)

What action do I need to take to fix this problem?

Partners are strongly advised to immediately:

  • Upgrade all affected clients to AhsayOBM v8.5.0.150 or above.
  • After upgrading to AhsayOBM v8.5.0.150 or above, if in-file delta is enabled on the backup set. The first backup job run a mandatory differential backup job.
  1. If your current AhsayCBS version IS NOT AhsayCBS v8.5.0.127 or above, then upgrade your AhsayCBS to v8.5.0.127 first. Please refer to these KB article for upgrade instructions:
  1. If your current version is already AhsayCBS v8.5.0.127 or above, then simply apply the latest hotfix AhsayCBS v8.5.0.150 or above from the partners portal. Please refer to hotfix upgrade instructions: (a valid partner portal account is required)

What if my maintenance has already expired? How do I upgrade?

Stop! Do not upgrade until you contact a member our Sales team for assistance with your maintenance renewal.

What if I require assistance with my AhsayCBS server upgrade?

Our professional service team is ready to provide immediate assistance to partners with AhsayCBS v8 upgrades.

Please contact a member our Sales team to obtain a quotation for the AhsayCBS upgrade service.

public/announcement/ahsay_upgrade_advisory_30181.1619591714.txt.gz · Last modified: 2021/04/28 14:35 by yuk.cheng