The Veeam Backup for Microsoft Office 365 server role hosts the product’s management console and manages the attached proxies and repositories.
Run the same OS version as on proxy and repository servers to reduce compatibility issues and reduce support effort.
VBO leverages the Microsoft Jet Blue database which is built into the Microsoft operating system. As every OS version brings another built-in version of the Jet Blue database engine it is recommended to use the same OS version on all VBO infrastructure components to avoid incompatibility issues.
Also drilling down problems is much easier when all components run on the same operating system and have the same feature level, security settings and quirks.