dual-phase-bootup
Syntax
dual-phase-bootup;
Hierarchy Level
[edit system]
Description
You can prevent the device from reaching an amnesiac state post-reboot by
configuring the dual-phase-bootup feature before the reboot. When a device
has a scaled configuration or has a lot of constraints to be validated, upon
reboot it may take more than 45 minutes to finish. This lengthy reboot time
exceeds the limit set for the watchdog timer. The watchdog timer going off
can cause the device to reach an amnesiac state. To avoid reaching an
amnesiac state during a future reboot, configure the
dual-phase-bootup statement.
If you have configured the dual-phase-bootup statement before
the reboot, the device picks up the rescue configuration from the next
reboot. Post-reboot, the device’s operational state is active and the device
automatically loads the last-configured user configuration
(juniper.conf file), thus preventing the device
from reaching an amnesiac state.
To be able to commit the configuration for the
dual-phase-bootup statement, you must already have
created a rescue configuration (rescue.conf file). We
recommend that you have a minimal rescue configuration.
During device upgrades or downgrades, this feature enables a two-step restart
process. If the dual-phase-bootup statement is already
configured and committed, the device picks up the
rescue.conf file during any upgrade or downgrade.
The image is then validated against both the
rescue.conf file and the
juniper.conf file. An internal commit is
performed post-reboot, with the latest last-run user configuration being
committed. While this configuration is being committed, you cannot make any
changes to the configuration.
To check the status of an ongoing dual-phase bootup or to check if it is
enabled, use the show dual-phase-bootup-status operational
mode command.
Default
Dual-phase bootup is turned off by default.
Required Privilege Level
system—To view this statement in the configuration.
system-control—To add this statement to the configuration.
Release Information
Statement introduced in Junos OS Release 23.4R1.