Introduction

Upgrading VM compatibility means converting a VM from compatibility mode to full function mode after a cross-version live migration (such as migrating from HCI 6.0.0 R5 to HCI 6.8.0 or 6.9.0). This operation enables new features (such as L3 cache and disk space reclamation) of the destination cluster for the VM, allowing the VM to run without feature restrictions in the cluster.

1. Technical logic: After a cross-version live migration, a VM runs in compatibility mode (compatible with the QEMU version of the source cluster) by default, making some new features unavailable. Once the compatibility upgrade completes, the VM will be compatible with the QEMU version of the destination cluster and have full functionality. Supported versions: HCI 6.8.0 (with SPs installed) and HCI 6.9.0 and later. The source cluster must be of a version that supports cross-version live migration (such as x86‐based HCI 6.0.0 R5 or 6.2.0). Core values: The compatibility upgrade resolves feature restrictions after a cross-version migration, allows the VM to benefit from the performance optimization and new features of the destination cluster, and ensures long-term stable business operations.

Constraints and Restrictions

1. Prerequisites: The VM has been hot-migrated across clusters of different versions and is currently in compatibility mode (compatibility upgrade not performed).
2. Irreversibility: After the compatibility upgrade is complete, the VM cannot be migrated back to the source cluster. Confirm that migration back is not required before upgrading.
3. VM status: The VM must be in Off status. Choose an appropriate time period to perform the compatibility upgrade because the VM will be restarted during the upgrade.
4. Permissions: Only the administrator can perform the compatibility upgrade. The administrator's login password is required for verification.
5. Restrictions: If business services on the VM are abnormal before the compatibility upgrade, migrate the VM back to the source cluster for troubleshooting. The VM can no longer be migrated back to the source cluster after the compatibility upgrade.

Precautions

1. The VM will be restarted during the compatibility upgrade. Therefore, it is recommended to perform the upgrade during off-peak hours (such as early morning) to prevent business interruption. Create a snapshot or backup for the VM before upgrading so that service anomalies that occur afterwards can be quickly fixed using the snapshot or backup. If any service issue is detected after the cross-version live migration but before the compatibility upgrade, migrate the VM back to the source cluster for troubleshooting. Migration back to the source cluster is no longer supported after the compatibility upgrade is complete.
2. Perform the compatibility upgrade for VMs one by one. Do not upgrade multiple VMs at the same time because it will lead to high resource consumption of the destination cluster.

Steps

Step 1.Log in to SCP and go to Resource Center > VMs.

Step 2.Find the target VM, which was migrated across clusters of different versions and is currently in Off status. (If the VM status is On, click the more options button (···) in the Operation column and select Power Off first.) Then, click the more options button (···) in the Operation column and select Upgrade VM Compatibility.

Step 3.In the Upgrade VM Compatibility dialog, a message is displayed, indicating that the VM cannot be migrated back to the source cluster after the upgrade. Confirm the message and enter the password of the logged-in user (admin) for permission verification.

Step 4.Click OK to start the upgrade task. The VM will be restarted automatically. When Upgrade successful appears, the operation is complete.