Android/Fastboot
The commands provided in this documentation are intended for advanced users and developers who have a thorough understanding of the underlying system and its potential implications. Executing these commands can have serious consequences and may lead to unintended outcomes, including but not limited to data loss, device instability, or even bricking the device. It is highly recommended that you do not attempt any of the commands mentioned here unless you have a clear understanding of the risks involved and are willing to accept full responsibility for any consequences that may arise. These commands are typically hidden from regular users for a reason, as they can directly modify critical system components and may void your device's warranty. If you are unsure about the implications of a specific command or its suitability for your device, it is strongly advised to consult official documentation, forums, or seek assistance from experienced users or professionals before proceeding. Remember, by executing these commands, you assume all risks and liabilities associated with the actions taken on your device. Always exercise caution, backup important data, and proceed at your own discretion
Fastboot is a communication protocol used primarily with Android devices. It is implemented in a command-line interface tool of the same name and as a mode of the bootloader of Android devices. It is included with the Android SDK package used primarily to modify the flash filesystem via a USB connection from a host computer. It requires that the device be started in Fastboot mode. If the mode is enabled, it will accept a specific set of commands sent to it via USB using a command line. Fastboot allows to boot from a custom recovery image. Fastboot does not require USB debugging to be enabled on the device. Not all Android devices have fastboot enabled
- Android device manufacturers have the option to implement fastboot or other protocols.
- Before performing any of the commands, it is important to install the Android SDK Platform-Tools, which provide necessary tools like adb and fastboot.
- To enter fastboot mode during a cold boot process, press the combination of the volume down and power buttons for 7000ms. For devices already powered on, use the command "adb reboot
bootloader" or reboot to fastboot from the device's terminal application.
- Unlocking the bootloader is necessary to flash a custom system, but it will erase all data on the device. Users should carefully read the instructions specific to their device model before proceeding, as unlocking the bootloader may void the warranty.
- Nexus and Pixel devices released since 2014 require a multistep process to unlock the bootloader due to factory-reset protection.
- Enabling OEM unlocking and USB debugging in the device settings is required before unlocking the bootloader.
- Different modes like recovery mode, bootloader mode, fastboot mode, and FastbootD mode allow for various operations on the device. The transition to FastbootD mode involves rebooting to the bootloader via adb and then using the "fastboot reboot fastboot" command.
Installation
Android SDK Platform-Tools is a component for the Android SDK. It includes tools that interface with the Android platform, primarily adb and fastboot commands
root #emerge --ask dev-util/android-toolsBooting into Fastboot
Booting into Fastboot mode allows you to flash a device and perform various operations. To enter Fastboot mode during the cold boot process, press the combination of the volume down and power buttons for approximately 7 seconds. This method applies to all Android devices, regardless of the model, and can be used to restart the device in any state. Once the device restarts, continue holding the key combination until the device enters the Fastboot mode.
Alternatively, you can also reboot to Fastboot mode using the "adb reboot bootloader" command via ADB (Android Debug Bridge) or from a terminal application on the device. Directly rebooting to Fastboot mode from the device skips the need for ADB in the command.
user $adb reboot bootloaderUnlocking the Bootloader
To flash a custom system, the bootloader must be unlocked. However, it is important to note that the bootloader is locked by default. Unlocking the bootloader will result in the deletion of all user data for privacy and security reasons. This includes both private app data and shared data accessible over USB, such as photos and movies. Before proceeding with unlocking the bootloader, it is strongly advised to back up any important files on the device.
Once the bootloader is unlocked, it can be re-locked at any time if desired.
Before unlocking the bootloader, carefully review the instructions specific to your device model. It is important to note that some devices, such as Samsung, use an electronic fuse that can be affected by bootloader unlocking. If you are unsure of the implications or potential risks, it is recommended to seek information relevant to your specific device model. Additionally, unlocking the bootloader may void the warranty, depending on the manufacturer's policies. It is essential to read and understand the warranty terms and conditions. Please proceed with caution and at your own risk.
Unlocking Recent Devices
Factory-reset protection has been implemented on Nexus and Pixel devices released since 2014, starting with Nexus 6 and Nexus 9. These devices require a multistep process to unlock the bootloader due to this added security feature.
Bootloader Operations
Print Lock State
Prints the lock state information of the device's bootloader. This command provides details about whether the bootloader is locked or unlocked.
user $fastboot oem device infoCheck Secure Image for Bootloader
Checks the integrity of the secure image for the bootloader. This command verifies the authenticity and integrity of the bootloader image to ensure that it has not been tampered with.
user $fastboot oem check-imageUnlock Bootloader
Unlocks the bootloader of the device. The `<key>` parameter should be replaced with the unlock key provided by the device manufacturer. Unlocking the bootloader allows you to modify the device's firmware and install custom software.
user $fastboot oem unlock <key>Check State for FB
Checks the lock state information for Fastboot. This command provides details about whether Fastboot is locked or unlocked on the device.
user $fastboot oem lock-state infoDump Status for Bootloader
Dumps the status information for the device's bootloader. This command retrieves detailed information about the bootloader, including the current bootloader version, device-specific information, and other relevant details.
user $fastboot oem get-bootinfoDevice Information
Get Root Status
Checks the root status of the device. This command determines whether the device has root access or not. Root access provides administrative privileges and allows users to make changes to the system files and settings.
user $fastboot oem check-rootinfoRelock Bootloader
Relocks the bootloader of the device. This command locks the bootloader, preventing unauthorized modifications to the device's firmware. Relocking the bootloader ensures the integrity and security of the system.
user $fastboot oem relockErase Factory Reset Protection
Erases the Factory Reset Protection (FRP) on the device. FRP is a security feature that prevents unauthorized access to the device after a factory reset. This command allows you to remove the FRP protection.
user $fastboot oem frp-eraseUnlock Factory Reset Protection
Unlocks the Factory Reset Protection (FRP) on the device. This command allows you to bypass the FRP protection and gain access to the device after a factory reset.
user $fastboot oem frp-unlockRun eMMC Diagnostic
Runs the eMMC (embedded MultiMediaCard) diagnostic on the device. This command initiates a diagnostic test on the device's eMMC storage to check for any issues or errors.
user $fastboot oem emmc_diagDump eMMC Info
Dumps detailed information about the eMMC (embedded MultiMediaCard) on the device. This command retrieves information such as the eMMC manufacturer, model, capacity, and other relevant details.
user $fastboot oem emmc-dumpPrint Key Version
Prints the version of the device's keys. This command provides information about the cryptographic keys used for signing and verifying software updates on the device.
user $fastboot oem get_key_versionDump Battery Status (millivolts)
Dumps the battery status in millivolts. This command retrieves the voltage level of the device's battery, indicating its current power level.
user $fastboot oem battery_present_checkPrint HwNFF Version
Prints the version of the hardware and firmware. This command provides information about the hardware and firmware versions of the device.
user $fastboot oem get_hwnff_verPrint IMEI and Serial Number
Prints the IMEI (International Mobile Equipment Identity) and serial number of the device. The IMEI is a unique identifier for the device, while the serial number is a unique identifier assigned by the manufacturer.
user $fastboot oem get-psidPrint Firmware Model
Prints the model of the device's firmware. This command provides information about the specific firmware model installed on the device.
user $fastboot oem get-build-numberPrint Firmware Build
Prints the build version of the device's firmware. This command retrieves the firmware build information, including the build number and other relevant details.
user $fastboot oem get-product-modelPrint Devices Connected in Fastboot
Lists all the devices connected in fastboot mode. This command displays the serial numbers of all the devices that are currently connected to the system in fastboot mode.
user $fastboot devicesVariable Product Information
Print Device Info
Prints detailed information about the device. This command provides comprehensive information about the device, including the hardware specifications, software version, and other relevant details.
user $fastboot getvar allPrint Kernel
Prints the kernel version of the device. This command retrieves the version number of the device's kernel, which is the core component of the operating system.
user $fastboot getvar kernelPrint Bootloader Version
Prints the version of the device's bootloader. This command retrieves the version number of the bootloader, which is responsible for initializing the device's hardware and loading the operating system.
user $fastboot getvar version-bootloaderPrint Product
Prints the product name of the device. This command retrieves the product name of the device, which represents the specific model or variant.
user $fastboot getvar productPrint Device Board
Prints the board name of the device. This command retrieves the name of the device's board, which represents the hardware platform on which the device is built.
user $fastboot getvar boardPrint Secure Mode
Prints the security mode of the device. This command provides information about the security features and settings enabled on the device.
user $fastboot getvar securePrint HwRev
Prints the hardware revision of the device. This command retrieves the hardware revision number, which indicates the specific version or variant of the device's hardware.
user $fastboot getvar hwrevPrint Radio Info
Prints information about the device's radio. This command provides details about the cellular radio module installed on the device, including the radio version and other relevant information.
user $fastboot getvar radioPrint Storage Type
Prints the type of storage used by the device. This command retrieves information about the type of storage technology employed by the device, such as eMMC or UFS.
user $fastboot getvar storage-typePrint eMMC Info
Prints information about the eMMC (embedded MultiMediaCard) on the device. This command provides details about the eMMC storage, including the manufacturer, model, capacity, and other relevant information.
user $fastboot getvar emmcPrint UFS Info
Prints information about the UFS (Universal Flash Storage) on the device. This command retrieves details about the UFS storage, including the manufacturer, model, capacity, and other relevant information.
user $fastboot getvar ufsPrint RAM Info
Prints information about the RAM (Random Access Memory) on the device. This command provides details about the device's RAM capacity and other relevant information.
user $fastboot getvar ramPrint CPU Info
Prints information about the CPU (Central Processing Unit) on the device. This command retrieves details about the device's CPU, including the architecture, clock speed, and other relevant information.
user $fastboot getvar cpuPrint Device Serial Number
Prints the serial number of the device. This command retrieves the unique serial number assigned to the device by the manufacturer.
user $fastboot getvar serialnoPrint CID
Prints the CID (Carrier ID) of the device. The CID represents the specific carrier or network operator to which the device is associated.
user $fastboot getvar cidPrint Channel ID
Prints the channel ID of the device. The channel ID represents the specific distribution channel or market segment to which the device belongs.
user $fastboot getvar channelidDump Token
Dumps the token for the device. This command retrieves a token that can be used for specific operations or authentication purposes on the device.
user $fastboot getvar tokenDump Device Secure State
Dumps the secure state of the device. This command provides information about the security status and features enabled on the device.
user $fastboot getvar securestateDump Device Verity State
Dumps the verity state of the device. This command retrieves information about the verity status, which ensures the integrity of the device's system partition.
user $fastboot getvar verity-stateDump Warranty Void Info
Dumps information about the warranty void status of the device. This command provides details about whether the device's warranty has been voided or remains valid.
user $fastboot getvar iswarrantyvoidDump Max Download Size
Dumps the maximum download size supported by the device. This command retrieves the maximum size of the file that can be downloaded to the device.
user $fastboot getvar max-download-sizeDump Reboot Reason
Dumps the reason for the last device reboot. This command provides information about the cause or trigger that led to the device rebooting.
user $fastboot getvar reasonDump IMEI/IMEI2
Dumps the IMEI (International Mobile Equipment Identity) and IMEI2 of the device. The IMEI is a unique identifier for the device, while IMEI2 represents a second IMEI number if available.
user $fastboot getvar imeiuser $fastboot getvar imei2Dump MEID Info
Dumps the MEID (Mobile Equipment Identifier) information of the device. The MEID is a unique identifier used for CDMA (Code Division Multiple Access) devices.
user $fastboot getvar meidDump Factory Date Device Was Born
Dumps the factory date when the device was manufactured. This command retrieves the manufacturing date of the device.
user $fastboot getvar datePrint SKU Version
Prints the SKU (Stock Keeping Unit) version of the device. The SKU represents a specific version or variant of the device.
user $fastboot getvar skuPrint Carrier SKU
Prints the carrier-specific SKU (Stock Keeping Unit) of the device. The carrier SKU represents a version or variant of the device specific to a particular carrier or network operator.
user $fastboot getvar carrier_skuDump Battery Serial
Dumps the serial number of the device's battery. This command retrieves the unique serial number assigned to the device's battery.
user $fastboot getvar battidDump Battery Voltage
Dumps the voltage of the device's battery. This command retrieves the current voltage level of the device's battery, indicating its power status.
user $fastboot getvar battery-voltageDump ICCID
Dumps the ICCID (Integrated Circuit Card Identifier) of the device's SIM card. The ICCID uniquely identifies the SIM card associated with the device.
user $fastboot getvar iccidDump MD5 Value
Dumps the MD5 value of the device's customization. This command retrieves the MD5 hash value that represents the customization or modifications applied to the device.
user $fastboot getvar cust_md5Dump Max Sparse Size
Dumps the maximum size of a sparse image supported by the device. A sparse image is a file format used for efficient storage and transfer of binary data.
user $fastboot getvar max-sparse-sizeDump Alarm Status
Dumps the status of the power-off alarm on the device. This command provides information about the power-off alarm feature, which triggers an alarm when the device is powered off.
user $fastboot getvar poweroffalarmDump ro.carrier
Dumps the value of the `ro.carrier` property on the device. This command retrieves the carrier-specific value of the `ro.carrier` property, which represents the carrier or network operator name.
user $fastboot getvar ro.carrierDump ro.build.fingerprint Settings
Dumps the settings of the `ro.build.fingerprint` property on the device. This command retrieves the fingerprint settings, which represent the specific build configuration and details of the device.
user $fastboot getvar ro.build.fingerprintDump Baseband of Device
Dumps the baseband version of the device. The baseband version represents the software component responsible for controlling the device's cellular radio.
user $fastboot getvar version.basebandDump Kernel Version
Dumps the version of the device's kernel. The kernel version represents the core component of the operating system that manages system resources and provides essential services.
user $fastboot getvar kernel.versionDump Git Info
Dumps the Git information of the device. This command retrieves details about the Git repository associated with the device's software, including commit information and version details.
user $fastboot getvar gitDump Current Slot in Use
Dumps the current slot in use on the device. This command provides information about the active slot from which the device is currently booting.
user $fastboot getvar current-slotDump FRP Status
Dumps the FRP (Factory Reset Protection) status of the device. This command retrieves information about the status of FRP, which is a security feature that protects the device against unauthorized access.
user $fastboot getvar frp-stateDump SIM Slot
Dumps the number of SIM slots available on the device. This command retrieves the count of SIM slots present on the device.
user $fastboot getvar slot-countDump Booted Slot
Dumps the slot that the device booted from. This command provides information about the slot that the device is currently using for booting.
user $fastboot getvar slot-successfulDump Unbootable Slot
Dumps the slot that is unbootable on the device. This command provides information about the slot that cannot be used for booting the device.
user $fastboot getvar slot-unbootableDump Boot Retry Count
Dumps the number of times the device will boot from the active slot before changing to another slot. This command provides information about the boot retry count for the active slot.
user $fastboot getvar slot-retry-countDump Logical Block Size
Dumps the logical block size of the device. This command retrieves the size of the logical blocks used for data storage on the device.
user $fastboot getvar logical-block-sizeDump Erase Block Size
Dumps the erase block size of the device. This command retrieves the size of the erase blocks used for data storage on the device.
user $fastboot getvar erase-block-sizeDump Status for Userspace
Dumps the status of the userspace on the device. This command provides information about the current status of the userspace environment, including whether it is active or not.
user $fastboot getvar is-userspaceDump PCB Number
Dumps the PCB (Printed Circuit Board) part number of the device. This command retrieves the part number associated with the device's PCB.
user $fastboot getvar pcb-part-noDump Primary/Secondary Display
Dumps the status of the primary and secondary displays on the device. This command provides information about the device's display setup, including the primary and secondary display configurations.
user $fastboot getvar primary-displayuser $fastboot getvar secondary-displayDump Status for FDR
Dumps the status of FDR (Factory Data Reset) on the device. This command retrieves information about whether FDR is allowed or not, indicating whether a factory data reset can be performed on the device.
user $fastboot getvar fdr-allowedTips and Tricks
Discovering Fastboot Commands
Due to variations in fastboot implementation across different device models (excluding Samsung devices, which do not utilize fastboot), it can be challenging to determine the available commands for your specific device. In most cases, these commands are not publicly disclosed and are considered proprietary information. However, if you have root access on your device, it is possible to extract the bootloader image to gain insights into its contents and potentially discover the hidden commands.
To proceed with this method, follow the steps below after accessing the shell of your device:
- Determine the Bootloader Image Location:
- Change the directory to /dev/block/bootdevice/by-name by executing the command: cd /dev/block/bootdevice/by-name
- List all partitions and their directories by name using the command: ls -all
- The list will display various partition directories. Look for the one labeled aboot which represents the bootloader. The exact location of your bootloader partition may vary. For example, in the provided image, the bootloader partition is identified as aboot and located at /dev/block/mmcblk0pX. It is crucial to identify the correct directory for your device, as it will be referenced in the subsequent command.
- Dump the Bootloader:
root #dd if=/dev/block/<aboot_partition> of=$EXTERNAL_STORAGE/backup_aboot.img
Once you have obtained the bootloader image, you can employ tools like strings or similar utilities to analyze its contents and potentially discover hidden commands or additional information related to your device's fastboot implementation.
Performing operations at the bootloader level carries inherent risks and can potentially result in irreparable damage to your device if executed improperly. It is strongly advised to exercise caution and proceed with extreme care. Additionally, modifying the bootloader may void your device's warranty and could violate the terms of your device's license agreement. Only proceed if you have a thorough understanding of the potential risks involved and are willing to accept full responsibility for any consequences that may arise.