The "Allow Idle Reboot" command, introduced in iOS 18.4 and iPadOS 18.4, is designed to enable devices to automatically reboot after being idle for a specified period. This feature is particularly useful in scenarios where devices are left unused for extended periods, such as during school holidays, to ensure they remain secure and receive necessary updates.
However, as you've observed, this feature can cause issues in environments where devices are managed remotely via Mobile Device Management (MDM) systems. The automatic reboot can disconnect devices from Wi-Fi, preventing them from receiving MDM commands until they are manually unlocked.
According to Apple's official documentation, the "Allow Idle Reboot" command is off by default on supervised devices. It's important to note that this command is available only on supervised devices running iOS 18.4 or later. If your devices are supervised and running the appropriate iOS version, you can enable this command through your MDM solution.Apple Support
Regarding the .mobileconfig file you mentioned, it's possible that it was generated by an MDM solution or a third-party tool. The "unknown payload" status suggests that the configuration profile may not be fully recognized by the device, possibly due to compatibility issues or the need for specific MDM support.
As of now, there isn't a documented method to disable the idle reboot feature entirely. Some users have suggested that the feature is intended to enhance security, but it can be problematic in managed environments .Reddit
In summary, while the "Allow Idle Reboot" command is a useful feature for ensuring device security during periods of inactivity, it can present challenges in MDM-managed environments. Careful consideration and testing are recommended before deploying this feature to ensure it aligns with your organization's device management policies and operational needs.
My devices are all supervised. I've noticed that devices that have enrolled into Jamf since 18.4 don't seem to reboot.
For example, I have a test iPad on my desk I was using for testing Jamf Teacher that was enrolled last week and that has not rebooted. Meanwhile my work iPad that I enrolled years ago does seem to have rebooted.