adb-reboot

Reboot the device normally

$ adb reboot

$ adb reboot bootloader

$ adb reboot recovery

$ adb reboot sideload

adb reboot [bootloader|recovery|sideload|sideload-auto-reboot]

adb reboot restarts the connected Android device. Without arguments, it performs a normal reboot. With mode arguments, it can reboot into special modes like bootloader (fastboot), recovery, or sideload for flashing firmware or installing updates.

bootloader

Reboot into bootloader/fastboot mode for low-level flashing

Reboot into recovery mode for system recovery or updates

Reboot into sideload mode for ADB sideloading

Reboot into sideload mode and automatically reboot after sideload completes

Bootloader and recovery modes may require unlocked bootloader or specific device states. Some devices use vendor-specific boot modes. Rebooting to bootloader terminates the adb connection; use fastboot commands afterward.

adb reboot has been available since the initial Android SDK release in 2008. Boot mode options were added to facilitate ROM development and device recovery operations.

adb(1), fastboot(1)