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FASTBOOTPartitionsCaution

fastboot set_active <a|b|other>

Switch active boot slot on A/B device

Caution RequiredIf the target slot does not contain valid, bootable firmware, the phone will fail to boot until switched back.
What It Does

Changes the active bootable slot on dual-slot A/B partition architectures. Critical for recovering from a bad update on the other slot.

Command Syntax
Terminal
$fastboot set_active <a|b|other>
Usage Examples
$fastboot set_active a
$fastboot set_active b
$fastboot set_active other
Options & Flags
Flag / ParameterDescription
otherToggles active slot to whichever slot is not currently active.
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Prerequisites & Requirements
  • A/B dual-slot hardware architecture
Related Commands
fastboot getvar current-slot

Check active A/B slot partition

fastboot reboot

Reboot device out of Fastboot into Android

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