Cisco IOS XR ROM Monitor Guide, Release 3.4 - ROM Monitor Overview and Basic Procedures [Cisco IOS XR Software]

Table Of Contents

ROM Monitor Overview and Basic Procedures

ROM Monitor Overview

Entering ROM Monitor Mode

Resetting the Configuration Register and Reloading a DSC to ROM Monitor Mode

Manually Halting the Initialization Process During System Reload

ROM Monitor Commands

Commonly Used ROM Monitor Commands

Displaying the Available ROM Monitor Commands

Examples

Displaying the Configuration Register Setting

Environment Variable Settings

Frequently Used Environmental Variables

Displaying Environment Variable Settings

Entering Environment Variable Settings

Saving Environment Variable Settings

Viewing Chassis Serial Numbers (Cisco CRS-1 Routers)

Exiting ROM Monitor Mode

Resetting to EXEC Mode with CLI Commands

Resetting to EXEC Mode Using Prompts

ROM Monitor Overview and Basic Procedures

The ROM Monitor is a bootstrap program that initializes the hardware and boots the Cisco IOS XR software when you power on or reload a router. A version of the ROM Monitor software exists on each card. If the Cisco IOS XR software cannot boot on a card, the card startup ends in ROM Monitor mode. When you connect a terminal to a card that is in ROM Monitor mode, the ROM Monitor command-line interface (CLI) prompt is displayed:

Cisco CRS-1 Prompt
rommon B1> 
Cisco XR 12000 Series Router Prompt
rommon1> 
During normal operation, users do not see the ROM Monitor prompt or use ROM Monitor mode. ROM Monitor mode is only used in usual circumstances, such as reinstalling the entire software set, resetting the router password or specifying a configuration file to use at startup.

This chapter provides an overview of ROM Monitor concepts and operations. For instructions to perform various tasks in ROM Monitor mode, see the other chapters in this book.

This chapter includes the following main topics:

•ROM Monitor Overview

•Entering ROM Monitor Mode

•ROM Monitor Commands

•Displaying the Configuration Register Setting

•Environment Variable Settings

•Viewing Chassis Serial Numbers (Cisco CRS-1 Routers)

•Exiting ROM Monitor Mode

ROM Monitor Overview

The ROM Monitor software is known by many names. It is sometimes called ROMMON because of the CLI prompt in ROM Monitor mode. The ROM Monitor software is also called the boot software, boot image, or boot helper. On Cisco XR 12000 Series Routers, the Boothelper software is different from the ROM Monitor software, and it is described in About Boothelper in Cisco XR 12000 Series Routers.

Although it is distributed with routers that use the Cisco IOS XR software, ROM Monitor is a separate program from the Cisco IOS XR software. During normal startup, the ROM Monitor initializes the cards, and then control passes to the Cisco IOS XR software. After the Cisco IOS XR software takes over, ROM Monitor is no longer in use.

A copy of the ROM Monitor software exists on each card. If a card fails to boot the Cisco IOS XR software, the ROM Monitor software takes control and places the card in ROM Monitor mode. Because a card in ROM Monitor mode is not running the Cisco IOS XR software, that card will be unavailable for normal router operations.

When the Designated Secure Domain Router System Controller (DSDRSC) in an SDR is placed in ROM Monitor mode, the router operations are transferred to the standby DSDRSC (if available). If both the primary and standby DSDRSCs are in ROM Monitor mode, then the router operations cease since the Cisco IOS XR software is no longer running.

Understanding the role of the DSC

The active RP for the owner SDR is called the Designated Shelf Controller, or DSC. This card performs system-wide functions, including the creation of additional non-owner SDRs. If the DSC is placed in ROM Monitor mode, it is no longer running the Cisco IOS XR software. If a standby DSC is available, then the standby assumes router operations. If a standby DSC is not available or is also placed in ROM Monitor mode, then router operations will stop.

Designated Secure Domain Router System Controller (DSDRSC)

In addition to the DSC, each SDR in the system contains at least one DSDRSC. The DSDRSCs provide configuration and administrative functions for a single SDR only. The DSC also serves as the DSDRSC for the owner SDR.

Accessing ROMMON on the DSC

In most situations, you will only interact with ROM Monitor mode on the DSC (DSDRSC for the owner SDR). The DSC contains the admin configuration for the entire system, and distributes the required software to all the other nodes in the router. All of the tasks in this document describe ROM Monitor mode accessed via the DSC for the system.

Note The only time you will interact with a non-DSC node is when reinstalling the Cisco IOS XR software on the standby PRP of a Cisco XR 12000 Series Router. See Reinstalling Cisco IOS XR Software on Cisco XR 12000 Series Routers for more information.

Remember, the DSC is also the following:

•The active RP of rack 0.

•The DSDRSC for the owner SDR.

Environmental Variables and the Configuration Register

Two primary connections exist between ROM Monitor and the Cisco IOS XR software: the ROM Monitor environment variables and the configuration register. The ROM Monitor environment variables define the location of the Cisco IOS XR software and how to load it. After ROM Monitor has initialized the card, it uses the environment variables to locate and load the Cisco IOS XR software.

The configuration register is a software setting that controls how a card starts up. One of the primary uses of the configuration register is to control whether the card starts in ROM Monitor mode or EXEC mode. The configuration register is set in either ROM Monitor mode or EXEC mode as needed. Typically, you set the configuration register using the Cisco IOS XR software prompt on the active RP when you need to use ROM Monitor mode. When your maintenance in ROM Monitor mode is complete, you change the configuration register so the card will reboot with the Cisco IOS XR software.

Accessing ROM Monitor Mode with a Terminal Connection

When an RP is in ROM Monitor mode, you can access the ROM Monitor software only from a terminal connected directly to the Console port of the card. Because the Cisco IOS XR software (EXEC mode) is not operating, the nonmanagement interfaces (such as POS interfaces) are not accessible. Basically, all Cisco IOS XR software resources are unavailable. The hardware is there, but no configuration exists to make use of the hardware.

Network Management Access and ROM Monitor Mode

Some people get confused when they start to use ROM Monitor mode. It is important to remember that ROM Monitor mode is a router mode, not a mode within the Cisco IOS XR software. It is best to remember that ROM Monitor software and the Cisco IOS XR software are two separate programs that run on the same router. At any given time, the router is running one of these programs, but it never runs both at the same time.

One area that confuses people when using ROM Monitor and the Cisco IOS XR software is that area that defines the IP configuration for the Management Ethernet interface. Most router users get comfortable with configuring the Management Ethernet interface in the Cisco IOS XR software. When the router is in ROM Monitor mode, however, the router is not running the Cisco IOS XR software, so that Management Ethernet interface configuration is not available.

When you want to access other devices, such as a TFTP server, while in ROM Monitor mode on Cisco CRS-1s, you must configure the ROM Monitor variables with IP access information. On Cisco XR 12000 Series Routers, you must configure the Boothelper software, as described in About Boothelper in Cisco XR 12000 Series Routers.

Entering ROM Monitor Mode

The following sections describe two ways to enter ROM Monitor mode:

•Resetting the Configuration Register and Reloading a DSC to ROM Monitor Mode

•Manually Halting the Initialization Process During System Reload

Resetting the Configuration Register and Reloading a DSC to ROM Monitor Mode

In normal operating conditions, it should not be necessary to use ROM Monitor mode. If you do find it necessary to place a designated system controller (DSC) in ROMMON, make sure that the system is in a steady state and that you are prepared for the consequences of a system reload. In particular, verify the items described in the "Prerequisites" section.

Prerequisites

Before you place a DSC in ROM Monitor mode, verify that the system is in a steady state:

1. Prepare the DSC:

a. Anticipate substantial downtime, including the loss of packet forwarding on the system.

b. Verify the sanity of the configuration file system using the command cfs check in EXEC mode.

c. Verify that all changes to the active router configuration are saved with the commit command in any configuration mode.

d. Verify that all changes to the active software set are saved with the install commit command in Administration EXEC mode.

e. Verify that all install commit processes are complete with the show install committed command in Administration EXEC mode. This command displays the committed packages that become active during the next router boot.

2. Verify that the other nodes in the system are in a steady state:

a. If a standby DSC is installed, verify that it is in the "ready" state with the show redundancy command in EXEC mode.

b. Verify that all available nodes in the system are in IOS XR RUN state with the show platform command in EXEC mode.

After you have verified that the system is in a stable state, you can enter ROM Monitor mode by setting the configuration register setting and entering the reload command, as described in the following steps.

SUMMARY STEPS

1. Verify that the router is in a steady state.

2. Connect a terminal to the DSC console port and log in to the router.

3. admin

4. Place the DSC, or all RPs in ROM Monitor Mode:

•Place only the DSC in ROM Monitor mode:

a. config-register 0x0

b. exit

c. reload

•OR
Place all RPs in ROM Monitor mode:

a. config-register 0x0 location all

b. reload location all

DETAILED STEPS
Command or Action

Purpose

Step 1

Verify that the router is in a steady state.

Ensures that all configurations are saved and that no installation processes are running.

•See the "Prerequisites" section

Step 2

Connect a terminal to the DSC console port and log in to the router.

Connects a terminal or PC to the DSC console port and establishes a router management session.

•See "Connecting and Communicating with the Router" in the Cisco IOS XR Getting Started Guide for more information on connecting a terminal.

Step 3

admin
Example:

RP/0/RP0/CPU0:router# admin

Enters administration EXEC mode.
Step 4
config-register 0x0
exit
reload
or
config-register 0x0 location all
reload location all
Examples:

RP/0/RP0/CPU0:router(admin)# config-register 0x0
RP/0/RP0/CPU0:router(admin)# exit
RP/0/RP0/CPU0:router# reload
or
RP/0/RP0/CPU0:router(admin)# config-register 0x0 location all
RP/0/RP0/CPU0:router(admin)# reload location all
Enter the following commands to place only the DSC in ROM Monitor mode:

a. Enter the command config-register 0x0 to set the configuration register for ROM Monitor mode during the next card reload.

b. Enter the command exit to exit administration EXEC mode.

c. Enter the command reload to reload the DSC and enter ROMMON mode.

Note If there is a standby DSC, the configuration register on the standby DSC is also set to 0x0. When you place the active RP in ROM Monitor mode, the system fails over to the standby RP, which then becomes the active RP. If both RPs need to be in ROM Monitor mode, connect to the new active RP and enter the reload command.

OR

Enter the following commands to place all RPs and SCs in ROM Monitor mode:

a. Enter the config-register 0x0 location all command to reset the configuration register for all RPs in the system.

b. Enter the reload location all command in administration EXEC mode to reload all RPs in the system.

Caution Resetting the configuration register may change the baud rate for the console.
Tip To verify the configuration register setting, enter the show variables boot command administration EXEC mode.

Examples

The following examples show how to place the DSC in ROM Monitor mode:

•Verifying the Router State: Example

•Placing the DSC in ROM Monitor Mode: Example

Verifying the Router State: Example

The following example shows the redundancy roles of both RPs and that both are operating in IOS XR RUN state:
RP/0/RP0/CPU0:router# show redundancy
Redundancy information for node 0/RP0/CPU0:
==========================================
Node 0/RP0/CPU0 is in ACTIVE role
Partner node (0/RP1/CPU0) is in STANDBY role
Standby node in 0/RP1/CPU0 is ready
RP/0/RP0/CPU0:router# show platform
Node            Type            PLIM            State           Config State
-----------------------------------------------------------------------------
0/1/CPU0        MSC             Jacket Card     IOS XR RUN      PWR,NSHUT,MON
0/1/0           MSC(SPA)        4XOC3-POS       OK              PWR,NSHUT,MON
0/1/5           MSC(SPA)        8X1GE           OK              PWR,NSHUT,MON
0/6/CPU0        MSC             Jacket Card     IOS XR RUN      PWR,NSHUT,MON
0/6/0           MSC(SPA)        4XOC3-POS       OK              PWR,NSHUT,MON
0/6/4           MSC(SPA)        8XOC3/OC12-POS  OK              PWR,NSHUT,MON
0/6/5           MSC(SPA)        8X1GE           OK              PWR,NSHUT,MON
0/RP0/CPU0      RP(Active)      N/A             IOS XR RUN      PWR,NSHUT,MON
0/RP1/CPU0      RP(Standby)     N/A             IOS XR RUN      PWR,NSHUT,MON
Placing the DSC in ROM Monitor Mode: Example

The following example shows how to place the DSC in ROM Monitor mode. This example is for a Cisco XR 12000 Series Router.
RP/0/0/CPU0:router# admin
RP/0/0/CPU0:router(admin)# config-register 0x0
Successfully set config-register to 0x0 on node 0/0/CPU0
Successfully set config-register to 0x0 on node 0/1/CPU0
RP/0/0/CPU0:router(admin)# exit
RP/0/0/CPU0:router# reload
Proceed with reload? [confirm]
System Bootstrap, Version 12.0(20040624:164256) [assafb-misc1 1.14dev(0.91)] DEV
ELOPMENT SOFTWARE
Copyright (c) 1994-2004 by cisco Systems, Inc.
DRAM DIMM Slot 1: 512M found, Slot 2: Empty
MPC7450 platform with 524288 Kbytes of main memory
rommon 1 >
Manually Halting the Initialization Process During System Reload

To force the DSC to stop loading and enter ROM Monitor mode, press Ctrl-C when you see the following message:
MBI validation sending request.
HIT CTRL-C to abort
This message usually appears during the first 20 seconds of system startup. It may be necessary to press the Ctrl-C keys repeatedly during this time to ensure that the initialization process stops and the system enters ROMMON.

This operation can be performed only from a terminal directly connected to the DSC console port. See "Connecting and Communicating with the Router" in Cisco IOS XR Getting Started Guide for more information.

Note When the DSC is placed in ROMMON, it switches over to the standby DSC, which can then also be placed in ROMMON. Repeat this process for both RPs.

ROM Monitor Commands

The commands in ROM Monitor are different from those available in the Cisco IOS XR software. You can run ROM Monitor commands only while in ROMMON, and you cannot run Cisco IOS XR software commands. This section includes the following topics:

•Commonly Used ROM Monitor Commands

•Displaying the Available ROM Monitor Commands

Commonly Used ROM Monitor Commands

The commands commonly used in ROM Monitor are summarized in Table 1-1. For specific instructions to use these commands, refer to the relevant procedure in this document.

Table 1-1 Commonly Used ROM Monitor Commands

ROMMON Command

Description

boot image

Manually boots a vm Cisco IOS XR software image.

boot image -o config-file-path

Manually boots the Cisco IOS XR software with a temporary alternative Administration configuration file.

boot image -a config-file-path

Manually boots the Cisco IOS XR software with an alternative secure domain router (SDR) configuration file.

confreg

Changes the config-register setting.

dev

Displays the available local storage devices (for example, disk0 and disk1).

dir

Displays the files on a storage device.

dumpplaneeeprom

Displays the chassis serial number in a Cisco CRS-1 router.

reset

Resets the node.

set

Displays the currently set ROM Monitor environmental settings.

sync

Saves the new ROM Monitor environmental settings.

unset

Removes an environmental variable setting.

version

Displays the ROM Monitor version.

Displaying the Available ROM Monitor Commands

Table 1-2 describes the available help commands for ROM Monitor mode.

Table 1-2 Help Commands in ROMMON

Command

Description

help or ?

Displays a summary of all available ROM Monitor commands.

-?

Displays information about command syntax.

Note Commands are case sensitive. You can halt any command by pressing Ctrl-C.

Examples

The following example shows what appears when you enter the ? command on a Cisco CRS-1:
rommon B5 > ?
alias               set and display aliases command
show_bcm_links      Show Links status on Broadcom Switches
show_bcm            Show Broadcom Switches Information
boot                boot up an external process
confreg             configuration register utility
cont                continue executing a downloaded image
context             display the context of a loaded image
dev                 list the device table
dir                 list files in file system
dis                 disassemble instruction stream
dnld                serial download a program module
help                monitor builtin command help
history             monitor command history
meminfo             main memory information
dumpspd             Dump the Serial Presents Detect info from the SDRAM DIMMs
dumpplaneeeprom     Dump the contents of the back plane
repeat              repeat a monitor command
reset               system reset
scanpci0            scan for devices on PCI bus 0
scanpci1            scan for devices on PCI bus 1
set                 display the monitor variables
smptest             Test the other CPU on an SMP board
sync                write monitor environment to NVRAM
tftpdnld            tftpdnld no longer available, use boot
unalias             unset an alias
unset               unset a monitor variable
version             display rommon software, board, version
writei2c            Write to an I2C device
rommon B2 >
The following example shows the parameters for the dir (directory) command:
rommon 7 > dir -?
bad device name
usage: dir <device>
Displaying the Configuration Register Setting

To display the current configuration register setting, enter the confreg command without parameters as follows:
rommon B1 > confreg 
           Configuration Summary
   (Virtual Configuration Register: 0x0)
enabled are:
console baud: 9600
boot: the ROM Monitor
do you wish to change the configuration? y/n  [n]:
The configuration register setting is labeled Virtual Configuration Register. Enter no to avoid changing the configuration register setting. To change the configuration setting with this command, see the "Resetting to EXEC Mode Using Prompts" section.

Environment Variable Settings

The ROM Monitor environment variables define the attributes of the ROM Monitor such as the IP address for an RP control Ethernet port, or the location of the Cisco IOS XR software and how to load it. Environmental variables are entered like commands and are always followed by the equal sign (=). Environment variable settings are entered in capital letters, followed by a definition For example:
TURBOBOOT=on,disk0,format
Under normal operating conditions, you will not need to modify these variables. They are cleared or set only when you need to make changes to the way ROM Monitor operates.

This section includes the following topics:

•Frequently Used Environmental Variables

•Displaying Environment Variable Settings

•Entering Environment Variable Settings

•Saving Environment Variable Settings

Frequently Used Environmental Variables

Table 1-3 shows the main ROMMON environmental variables. For instructions to use these variables, see the relevant instructions in this document.

Table 1-3 Frequently Used ROM Monitor Environmental Variables

Environmental variable

Description

IP_ADDRESS=ip_address

On the Cisco CRS-1 RP only. Sets the IP address for the Management Ethernet interface on the DSC.

IP_SUBNET_MASK=ip_address

On the Cisco CRS-1 RP only. Sets the subnet mask for the Management Ethernet interface on the DSC.

DEFAULT_GATEWAY=ip_address

On the Cisco CRS-1 RP only. Sets the default gateway that serves the DSC.

TFTP_SERVER=ip_address

Sets the IP address of the TFTP server where a bootable software image is located.

TFTP_FILE=drive:path/file

Sets the directory and filename of a a bootable software image.

TURBOBOOT=on, boot-device, options

Completely replaces the existing software when the router is reloaded.

BOOT=drive:path/file

Identifies the boot software for a node. This variable is usually set automatically when the router boots.

AUX_AUTHEN_LEVEL=number

Bypasses ksh authentication. A reboot is required only on the card that has to bypass authentication.

IOX_ADMIN_CONFIG_FILE=
drive:path/file

Permanently changes the location of the default Administration configuration file.

IOX_CONFIG_FILE=drive:path/file

Permanently changes the location of the secure domain router (SDR) configuration file.

IOX_CONFIG_MEDIUM=drive:path

Permanently changes the default location where configuration files are saved.

Displaying Environment Variable Settings

To display the current environment variable settings, enter the set command as follows:
rommon B1 > set
PS1=rommon ! >
TFTP_VERBOSE=2
IP_ADDRESS=1.1.1.1
IP_SUBNET_MASK=255.255.0.0
TFTP_SERVER=
DEFAULT_GATEWAY=12.25.0.1
TFTP_FILE=
CONFIG_FILE=
BOOT=disk0:hfr-os-mbi-1.0.0/mbihfr-rp.vm,1;
rommon B2 >
Entering Environment Variable Settings

Environment variable settings are entered in capital letters, followed by a definition. The following example shows the environmental variables used to configure the control Ethernet port on a Cisco CRS-1 router.
rommon B1> IP_ADDRESS=1.1.1.1
rommon B2> IP_SUBNET_MASK=255.255.254.0
rommon B3> DEFAULT_GATEWAY=1.1.0.1
Saving Environment Variable Settings

To save the current environment variable settings, enter the sync command as follows:
rommon B1 > sync
Note Environmental values that are not saved with the sync command are discarded whenever the system is reset or booted.

Viewing Chassis Serial Numbers (Cisco CRS-1 Routers)

The chassis serial number is required for multishelf routers and can be read from an SC or RP that is running in ROM Monitor mode. This may be necessary if the physical label is missing or damaged.

Note You can view the chassis serial numbers using the Cisco IOS XR software. For more information, see "Displaying the Chassis Serial Numbers (Cisco CRS-1 Routers)" in Cisco IOS XR Getting Started Guide.

Step 1 Attach a console to the console port of an SC or RP in the chassis. (Only the SC or RP needs to run to perform this procedure. Other cards need not be inserted.)

Step 2 If you have not already done so, apply power to the chassis.

Step 3 Enter ROM Monitor mode, as described in the "Entering ROM Monitor Mode" section.

Step 4 Enter the ROMMON command dumpplaneeeprom in the privilege mode of ROMMON to display the chassis serial number. In the following example, the serial number is TBC0636606900000.
rommon B3 > 
rommon B3 > priv 
rommon B3 > dumpplaneeeprom 
EEPORM data backplane
000000  00 00 01 e2 00 00 00 00 00 00 00 00 00 00 00 00 ................
000010  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000020  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000030  00 00 00 00 00 00 08 00 45 3b 61 01 04 00 00 00 ........E;a.....
000040  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000050  54 42 43 30 36 33 36 36 30 36 39 30 30 30 30 30 TBC0636606900000
000060  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000070  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000080  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
000090  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
0000a0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
0000b0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
0000c0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
0000d0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
0000e0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
0000f0  00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
Note The chassis serial number is displayed in the output to the right (row "00050"). A similar number is present for every chassis.

Step 5 Return the router to EXEC mode, as described in the "Exiting ROM Monitor Mode" section.

Exiting ROM Monitor Mode

To exit ROM Monitor mode, you must change the configuration register to 0x2102 and reset the RP. This process can be done by either entering CLI commands or responding to prompts.

Tip The first RP to enter EXEC mode becomes the DSC. You can determine which RP is the DSC by resetting that card to EXEC mode first and then waiting 1 to 2 minutes to allow it to boot fully. You can also fail over to the standby DSDRSC at any time with the redundancy switchover command in EXEC mode.

The following sections describe ways to exit ROM Monitor mode:

•Resetting to EXEC Mode with CLI Commands

•Resetting to EXEC Mode Using Prompts

Resetting to EXEC Mode with CLI Commands

Perform this task to reset the configuration register in ROMMON and start the RP in EXEC mode.

SUMMARY STEPS

1. confreg 0x2102

2. reset

DETAILED STEPS

Command or Action

Purpose

Step 1

confreg 0x2102
Example:

rommon B1> confreg 0x2102

Resets the configuration register to enter EXEC mode when the system is reset.

Step 2

reset
Example:

rommon B1> reset

Resets and initializes the router.

Resetting to EXEC Mode Using Prompts

In ROM Monitor mode, you can also change the configuration register value using the configuration register prompts.

Enter the confreg command, as shown in the following example, and respond to each question when prompted.

SUMMARY STEPS

1. confreg

2. Respond to each prompt as instructed.

3. reset

DETAILED STEPS

Command or Action

Purpose

Step 1

confreg
Example:

rommon B1> confreg 0x2102

Initiates the configuration register configuration prompts.

Step 2

Respond to each prompt as instructed.

For more information, see the example that follows this procedure.

Step 3

reset
Example:

rommon B1> reset

Resets and initializes the router.

Examples

The following example shows the commands required and the prompts that appear when you reset the RP to EXEC mode using the configuration register prompts:
rommon B1> confreg
           Configuration Summary
   (Virtual Configuration Register: 0x0)
enabled are:
console baud: 9600
boot: the ROM Monitor
do you wish to change the configuration? y/n  [n]:  y
enable  "diagnostic mode"? y/n  [n]: n
change console baud rate? y/n  [n]:  n
change the boot characteristics? y/n  [n]: y
enter to boot:
 0 = ROM Monitor
 1 = MBI Validation Boot Mode
    [0]:  1
           Configuration Summary
   (Virtual Configuration Register: 0x2102)
enabled are:
console baud: 9600
boot: image specified by the boot system commands
do you wish to change the configuration? y/n  [n]: n
You must reset or power cycle for new config to take effect
rommon B2> reset
Note Minimum Boot Image (MBI) validation mode causes the RP to boot the startup Cisco IOS XR software and configuration.