Hi Toby Pope,
Thank You for reaching out to Microsoft Q&A forum.
As per Microsoft Official documentation, Azure Update Manager is currently supported for 35 CIS hardened images. https://learn.microsoft.com/en-us/azure/update-manager/whats-new#august-2024
As you stated above, you are following the self-manged methods for update process, but currently, Azure Supported Manager supports for other cis hardened image Linux distributions but not for cis-alma Linux distribution.
Currently, Microsoft doesn't have an estimated timeline on when support for cis-alma Linux 8.10 will be available in Azure Update Manager.
Currently, Azure Disk Encryption is supported for Ubuntu, RHEL, CentOS etc linux distribution system but not Alma Linux distribution system. https://learn.microsoft.com/en-us/azure/virtual-machines/linux/disk-encryption-overview#supported-operating-systems
Since there is no fixed timeline for Azure Disk Encryption support for the Alma Linux distribution.
Please check official documentation for more information:
https://learn.microsoft.com/vi-vn/azure/virtual-machines/disk-encryption-overview
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