Chapter - Cisco ASR 5000 Series Administration Manual

System Recovery
This chapter describes how to recover a system after it has failed to complete a reboot following a power
off cycle or interruption of the normal boot sequence following a reload command.
This system recovery process interrupts subscriber service by dropping any existing flows and preventing
Caution
traffic from being processed during the boot interval. It should only be initiated as an emergency measure.
This chapter includes the following sections:
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Prerequisites
Recovery from a failed reboot requires that you have access to the system via a console port, and have an
uncorrupted copy of the StarOS boot image file stored in flash memory on the management card, or accessible
from an external memory device.
Console Access
Boot recovery can only be executed via a terminal connected to the serial console port on the active management
card. This connection can be through a terminal server that is accessible via a LAN interface. Boot recovery
can only be viewed via the console port.
Boot Image
The boot recovery command line interface enables you to specify from which boot image you would like to
boot the system. If the system failed to reload following a software update, you can initiate a boot from a
previously stored image.
Prerequisites, page 243
Accessing the boot CLI, page 244
Booting from a Selected Image, page 245
C H A P T E R
ASR 5500 System Administration Guide, StarOS Release 21.4
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