Cisco CSR 1000v Series User Manual

CHAPTER 13
Accessing and Using GRUB Mode
•
About GRUB Mode and the Configuration Register, page 221
•
Accessing GRUB Mode, page 223
•
Using the GRUB Menu, page 223
•
Modifying the Configuration Register (confreg), page 224
•
Changing the Configuration Register Settings, page 226
•
Displaying the Configuration Register Settings, page 227
About GRUB Mode and the Configuration Register
The Cisco CSR 1000v has a 16-bit configuration register in NVRAM. Each bit has value 1 (on or set) or value
0 (off or clear), and each bit setting affects the router behavior upon the next reload power cycle. The Cisco
CSR 1000v GRUB mode supports a subset of configuration register options compared to ROMMON options
on other Cisco routers.
You can use the configuration register to:
•
Force the router to boot into the GRUB (bootstrap program)
•
Select a boot source and default boot filename
•
Recover a lost password
The table below describes the configuration register bits.
Cisco CSR 1000v Series Cloud Services Router Software Configuration Guide
221

Cisco CSR 1000v Series Specifications

General

Brand	Cisco
Model	CSR 1000v Series
Category	Network Router
Language	English