Knowledge Search


×
 

[SRX] How is the boot partition selected in dual-boot partition

  [KB23710] Show Article Properties


Summary:
This article provides information on how to select the boot partition in dual-boot partition devices.
Symptoms:
How to select the boot partition in dual-boot partition devices.
Solution:
When the device is rebooted, Uboot marks a partition as the primary, from which the device should boot and Uboot sets a flag for that primary partition and informs the loader. When the loader starts loading the kernel and OS, it verifies the information received from Uboot and starts loading the kernel and OS from the same partition, which was selected by Uboot. Once the OS is completely loaded, the loader informs Uboot that the OS was loaded from the same partition, which was selected by Uboot.

In case Uboot does not receive the confirmation from the loader, then in the next boot Uboot change the boot partition and selects the backup partition as the boot partition and sets the flag. This information is passed to the loader. Now the device will boot from the backup partition.

If you boot the device, which was booted from the backup partition, it follows the same process; that is it will mark the primary partition as the boot partition by setting the flag and the information is passed to the loader.
 
Modification History:

2017-11-02: Added new SRX 300 series to product categories.

Related Links: