Oracle Linux VM Restored to Azure Fails to Boot
Challenge
Cause
Some Oracle Linux deployments may not include the Hyper-V-related UEK (Unbreakable Enterprise Kernel) modules, such as:
- hv_vmbus
- hv_storvsc
- hv_utils
- hv_netvsc
When these modules are missing, issues can occur during VM recovery or conversion on Hyper-V-based Azure infrastructure.
The following error may be seen in the logs during VM conversion:
Info (3) dracut-install: Failed to find module 'hv_storvsc' Info (3) dracut: FAILED: /usr/lib/dracut/dracut-install -D /var/tmp/dracut.EaHvEj/initramfs --kerneldir /lib/modules/5.15.0-306.177.4.el8uek.x86_64/ -m hv_vmbus hv_storvsc hv_utils hv_netvsc
This failure prevents proper driver inclusion in the initramfs, leading to boot failure in the Azure environment.
Solution
Install kernel UEK Modules
To resolve the issue:
- Install the kernel UEK modules package on the original VM corresponding to the current kernel version.
- Create a new restore point.
- Reattempt the restore using the new restore point.
The following command will install the kernel-specific UEK modules, ensuring the missing Hyper-V modules can be included in the initramfs.
dnf command does not work, try the following yum command:
Verify UEK Module Install
The following command can be used to verify that the kernel-uek-modules package was installed correctly and contains the necessary Hyper-V modules:
"kernel-uek-modules" build string or the message "package kernel-uek-modules is not installed".
Review kernel Modules and initramfs Images
Use the following command to review the available kernel modules:
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