Thank you for posting your query on Microsoft Q&A. From above description I could understand that you have a Linux VM in Azure on which you have Enabled Azure AD login, but the device is not visible in Azure AD all devices.
Please do correct me if this is not the case by responding in the comments section.
You could manage only Azure AD registered, Azure AD joined and Hybrid AD joined devices from Azure AD > All devices blade. In the above scenario the device does not get any type of join hence it won't be visible among all devices in AAD.
Linux VM's does not support AAD join or Hybrid AD join. They support only AAD registration which could be done only by enrolling the device to Microsoft Intune.
- In the above described scenario an AAD user could sign into the device via SPN of Microsoft Azure Linux Virtual Machine Sign-In application which gets registered in AAD once you enable AAD SSH extension (gets auto enabled when you select Azure AD authentication). So user gets access to the VM via this app and not a direct access like windows VM. So every time user signs into Linux VM there would be a signin log generated for Microsoft Azure Linux Virtual Machine Sign-In application
Please do let me know if you have any further queries.
Thanks,
Akshay Kaushik
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