Cisco ASR 9000 Series Aggregation Services Router ROM Monitor Configuration Guide, Release 5.2.x
ROM Monitor Overview
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ROM Monitor Overview

Contents

ROM Monitor Overview

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

This chapter includes the following main topics:

Information About ROM Monitor

The ROM Monitor is a bootstrap program that initializes the ASR 9000 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 and is factory supplied. The ROM Monitor program provides an initial power-on environment for each card. If the Cisco IOS XR software is rebooted or unable to run, the corresponding card returns to the ROM Monitor mode.

When you connect a terminal to a card that is in the ROM Monitor mode, the ROM Monitor CLI prompt is displayed.

Cisco ASR 9000 Series Router Prompt


rommon B1>

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.

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.

Understanding the Role of the Route Switch Processor (RSP) Card

The Cisco ASR 9000 Series Router contains series of chassis slots, each of which can hold one of several types of line cards (LCs). Two slots in the chassis are reserved for route switch processors (RSP) cards that provide the central point for chassis provisioning and management.

The active RSP for the owner SDR is called the Designated Shelf Controller (DSC). This card performs system-wide functions. If the active RSP card is placed in ROM Monitor mode, it is no longer running the Cisco IOS XR software. If a standby RSP card is available, then the standby RSP card resumes router operations. If both the RSP cards are not available or if the active RSP (previously standby) is also placed in the ROM Monitor mode, router operations will stop.

Designated Secure Domain Router Shelf Controller (DSDRSC)

When the Designated Secure Domain Router Shelf 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 because the Cisco IOS XR software is no longer running.

Accessing ROM Monitor Mode on the RSP Card

In most situations, you interact with the ROM Monitor mode only on the RSP cards. The active RSP card contains the administration configuration for the entire system and distributes the required software to all the other nodes in the router. All the tasks in this document describe ROM Monitor mode accessed through the RSP card for the system.

The line cards have its own ROM Monitor software which can be upgraded using the RSP FPD upgrade operation, if required.

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 describe 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 common environment variables are BOOT, IP_ADDRESS, DEFAULT_GATEWAY, TFTP_FILE, TURBOBOOT and SUBNET_MASK.

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 Administration EXEC mode. The configuration register is set in either ROM Monitor mode or Administration EXEC mode as needed. Typically, you set the configuration register using the Cisco IOS XR software prompt on the active RSP when you need to use ROM Monitor mode. When the maintenance in ROM Monitor mode is complete, you change the configuration register so the card reboots with the Cisco IOS XR software.


Note


Throughout this guide, the term RSP is used to refer to the RSP cards supported on Cisco ASR 9000 Series Routers. If a feature or an issue applies to only one platform, the accompanying text specifies the platform.


Accessing ROM Monitor Mode with a Terminal Connection

When an RSP 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 GigabitEthernet 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 can be confusing when using ROM Monitor and the Cisco IOS XR software is the 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.

To access other devices, such as a TFTP server, while in ROM Monitor mode on the Cisco ASR 9000 Series Router, you must configure the ROM Monitor variables with IP access information.

Entering ROM Monitor Mode

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

Prerequisites

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

  1. Prepare the RSP card:
    • Anticipate substantial downtime, including the loss of packet forwarding on the system.
    • Verify the sanity of the configuration file system using the cfs check command in EXEC mode.
    • Verify that all changes to the active router configuration are saved with the commit command in any configuration mode.
    • Verify that all changes to the active software set are saved with the install commit command in Administration EXEC mode.
    • 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. If any of the processes are not committed, use the install commit command in the Administration mode.
  2. Verify that the other nodes in the system are in a steady state:
    • If a standby RSP is installed, verify that it is in the ready state with the show redundancy command in EXEC mode.
    • 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:

Resetting the Configuration Register and Reloading a RSP Card 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 RSP card in ROM Monitor mode, make sure that the system is in a steady state and that you are prepared for the consequences of a system reload.

SUMMARY STEPS

    1.    Verify the router is in a steady state.

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

    3.    admin

    4.    config-register boot-mode rom-monitor location <node-id> exit reload or config-register boot-mode rom-monitor location all reload location all


DETAILED STEPS
     Command or ActionPurpose
    Step 1Verify the router is in a steady state. 

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

     
    Step 2Connect a terminal to the RSP card console port and log in to the router. 

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

    For more information on connecting a terminal, see Connecting and Communicating with the Router in Cisco ASR 9000 Series Aggregation Services Router Getting Started Guide.

     
    Step 3admin


    Example:
    RP/0/RSP0/CPU0:router# admin
     

    Enters administration EXEC mode.

     
    Step 4config-register boot-mode rom-monitor location <node-id> exit reload or config-register boot-mode rom-monitor location all reload location all


    Example:
    RP/0/RSP0/CPU0:router(admin)# config-register boot-mode rom-monitor location 0/RSP0/CPU0
    
    RP/0/RSP0/CPU0:router(admin)# exit
    RP/0/RSP0/CPU0:router# reload
    Or,
    RP/0/RSP0/CPU0:router(admin)# config-register boot-mode rom-monitor 
    location all
    RP/0/RSP0/CPU0:router(admin)# reload location all
    
     
    • Enter the following commands to place only one RSP card (active or standby) in ROM Monitor mode:
    • Enter the boot-mode rom-monitor location <node-id> command, where <node-id> is the ID of the card, to set the configuration register for ROM Monitor mode during the next card reload.
    • Enter the exit command to exit administration EXEC mode.
    • Enter the reload command to reload the card and enter ROM Monitor mode.
      Note   
      • If you specify the config-register boot-mode rom-monitor command without the location keyword, then all the RSPs are placed in ROM Monitor mode.
    • Enter the following commands to place all RSPs in ROM Monitor mode:
    • Enter the config-register boot-mode rom-monitor location all command to reset the configuration register for all RSPs in the system.
    • Enter the reload location all command in administration EXEC mode to reload all RSPs in the system.
    Note   

    Make sure you have access to the console ports of both RSP0 and RSP1 cards on the system. To enter the system to the ROM Monitor mode, press Ctrl-C a few times on both RSP0 and RSP1 consoles until you get to the ROM Monitor mode.

    Caution   

    Resetting the configuration register may change the baud rate for the console. The default baud rate is 9600.

    Tip   

    To verify the configuration register setting, enter the show variables boot command in the administration EXEC mode.

     

    Verifying the Router State: Example

    The following example shows the redundancy roles of both RSPs and shows that both are operating in IOS XR RUN state:

    
    RP/0/RSP0/CPU0:router#show redundancy
    
    Wed Jun 30 21:35:23.656 UTC
    Redundancy information for node 0/RSP0/CPU0:
    ==========================================
    Node 0/RSP0/CPU0 is in ACTIVE role
    Partner node (0/RSP1/CPU0) is in STANDBY role
    Standby node in 0/RSP1/CPU0 is ready
    Standby node in 0/RSP1/CPU0 is NSR-ready
    
    Reload and boot info
    ----------------------
    A9K-RSP-8G reloaded Tue Jun 29 18:56:15 2010: 1 day, 2 hours, 39 minutes ago
    Active node booted Tue Jun 29 18:56:15 2010: 1 day, 2 hours, 39 minutes ago
    Standby node boot Tue Jun 29 18:55:54 2010: 1 day, 2 hours, 39 minutes ago
    Standby node last went not ready Tue Jun 29 18:58:52 2010: 1 day, 2 hours, 36        
    minutes ago
    Standby node last went ready Tue Jun 29 18:59:52 2010: 1 day, 2 hours, 35 minutes    
    ago
    There have been 0 switch-overs since reload
    
    Active node reload "Cause: Node reload is required by install operation"
    Standby node reload "Cause: pID node reload is required by install operation"
    
    RP/0/RSP0/CPU0:router#show redundancy summary
    Wed Jun 30 21:35:32.259 UTC
        Active Node    Standby Node
        -----------    ------------
        0/RSP0/CPU0     0/RSP1/CPU0 (Ready, NSR: Ready)
    
    RP/0/RSP0/CPU0:router#show platform
    
    Wed Jun 30 21:35:35.944 UTC
    Node            Type                      State            Config State
    -----------------------------------------------------------------------------
    0/RSP0/CPU0     A9K-RSP-8G(Active)        IOS XR RUN       PWR,NSHUT,MON
    0/RSP1/CPU0     A9K-RSP-8G(Standby)       IOS XR RUN       PWR,NSHUT,MON
    0/1/CPU0        A9K-8T-E                  IOS XR RUN       PWR,NSHUT,MON
    0/5/CPU0        A9K-40GE-B                IOS XR RUN       PWR,NSHUT,MON
    0/6/CPU0        A9K-2T20GE-E              IOS XR RUN       PWR,NSHUT,MON
    
    

    Placing the RSP Cards in ROM Monitor Mode: Example

    The following example shows how to place the RSP in the ROM Monitor mode:

    
    RP/0/RSP0/CPU0:router# admin
    RP/0/RSP0/CPU0:router(admin)# config-register
    boot-mode rom-monitor location all 
    
    Set to rom-monitor mode for all mgmt nodes:
    RP/0/RSP0/CPU0:router(admin)#config-register boot-mode rom-monitor location all
    Successfully set config-register to RP/0/RSP0/CPU0:router
    Successfully set config-register to RP/0/RSP0/CPU0:router
    
    

    Manually Halting the Initialization Process During System Reload

    To force the RSP card 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
    TYPE 'Send Break'to abort
    

    This message usually appears during the first 20 seconds of system startup. Press the Ctrl-C key combination immediately. 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 ROM Monitor mode. This ends your Telnet session to the console or auxiliary port.

    This operation can be performed only from a terminal directly connected to the RSP card console port. For more information, see the “Connecting and Communicating with the Router” section in Cisco ASR 9000 Series Aggregation Services Router Getting Started Guide.


    Note


    When the RSP card is placed in ROMMON, it switches over to the standby RSP card, which can then also be placed in ROMMON. Repeat this process for both RSP cards.


    ROM Monitor Commands

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

    Commonly Used ROM Monitor Commands

    The table below summarizes the commands commonly used in ROM Monitor. For specific instructions on using these commands, refer to the relevant procedure in this document.

    Table 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 tftp://config-file-path/image

    Manually boots the Cisco IOS XR software with a temporary default SDR configuration file. The system can also be booted from external compactflash using Cisco ASR 9000 Series Router Image Refresh method.

    cookie

    Displays the system cookie.

    confreg

    Changes the config-register setting.

    Note   

    When the value of confreg is 0, it means autoboot is disabled and you need to manually boot the Cisco IOS XR software image from the ROM Monitor mode. However, if the value of confreg is non-zero value of 0x2, it means autoboot is enabled and the ROM Monitor mode automatically boots the Cisco IOS XR software image given in the BOOT= environment variable.

    dev

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

    dir

    Displays the files on a storage device.

    bpcookie

    Displays the chassis serial number, MAC address, MAC range, PID, Controller type, version, and so on, in a Cisco ASR 9000 Series 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

    The table below describes the available help commands for ROM Monitor mode.

    Table 2 Help Commands in ROMMON
     

    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.


    Displaying the Available ROM Monitor Commands: Examples

    The following example shows what appears when you enter the ? command on a Cisco ASR 9000 Series Router:

    rommon B1> ?
    alias               set and display aliases command
    boot                boot up an external process
    bpcookie            display the backplane cookie
    cbcinfo             Display information from CBC
    cbcmsg              Send a message to the CBC
    cbcping             Send "PING" to CBC LED Matrix
    clocks              get CPU clock information
    confreg             configuration register utility
    cookie              display the system cookie
    dev                 list the device table
    dir                 list files in file system
    dimminfo            Display info for DDR DIMMs
    dis                 disassemble instruction stream
    dnld                serial download a program module
    dump                display a block of memory
    ddump               display a block of memory as double words
    dumpspd             display DDR2 SPD information
    fpgainfo            display information about FPGA images
    ftcookie            display the fan tray cookie
    help                monitor builtin command help
    history             monitor command history
    meminfo             main memory information
    portstatus          Show 6 port switch port status
    repeat              repeat a monitor command
    reset               system reset
    showrobfl           show run logs
    rominfo             display the ROMMON header information
    scanpci1            scan for devices on PCI bus 1
    scanpci2            scan for devices on PCI bus 2
    set                 display the monitor variables
    sync                write monitor environment to NVRAM
    unalias             unset an alias
    unset               unset a monitor variable
    version             display rommon software, board, version
    

    The following example shows the parameters for the dir (directory) command:

    
    rommon B1> dir -?
    bad device name
    usage: dir <device>
    

    The following example shows what appears when you enter the version command at the Cisco ASR 9000 Series Router ROM Monitor mode prompt:

    
    rommon B1 > version
    
    System Bootstrap, Version 1.0(20081208:173612) [ASR9K ROMMON],
    Copyright (c) 1994-2008 by Cisco Systems, Inc.
    Compiled Mon 08-Dec-08 09:36 by abc
    
      LNC2:  1.17  [00000001/00000011]
      TMPO:  1.13  [00000001/0000000d]
      LB_3:  1.14  [00000001/0000000e]
      PUNT:  1.4   [00000001/00000004]
       CBC:  1.1
       BID: 0x0004
    

    Changing the ROM Monitor Prompt

    You can change the prompt in ROM Monitor mode by using the PS1= command as shown in the following example:

    
    rommon B1> PS1= “ASR9K_ROMMON B1 
    !>”
    

    Changing the prompt is useful if you are working with multiple routers in ROM Monitor at the same time. This example specifies that the prompt is ASR9K_ROMMON B followed by the line number.

    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: 0x1920)
    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 the no command to avoid changing the configuration register setting.

    Environment Variables

    The ROM Monitor environment variables define the attributes of the ROM Monitor, such as the IP address for an RSP control Ethernet port or the location of the Cisco IOS XR software and describe 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 do not need to modify these variables. They are cleared or set only when you need to make changes to the way ROM Monitor operates.


    Note


    Before loading CISCO IOS XR software image in Cisco ASR 9000 Virtualized Service Module (VSM) Service Card, you must ensure that these environment variables are set at the LC ROMMON prompt:
    • TFTP_EXTERNAL_BOOT=0
    • AUTOMATIC_BOOT=1

    Frequently Used Environmental Variables

    The table below shows the main ROM Monitor environmental variables. For instructions on how to use these variables, see the relevant instructions in this document.

    Environmental variable

    Description

    TFTP_MGMT_INTF={0 | 1}

    Description

    IP_ADDRESS=ip_address

    Description

    IP_SUBNET_MASK=ip_address

    Sets the subnet mask for the Management Ethernet interface on the RSP card.

    DEFAULT_GATEWAY=ip_address

    Description

    TFTP_SERVER=ip_address

    Description

    TFTP_FILE=drive:path/file

    Description

    TURBOBOOT=on, boot-device, options

    Sets the subnet mask for the Management Ethernet interface on the RSP card.

    BOOT=drive:path/file

    Sets the default gateway that serves the RSP card.

    BOOT_DEV_SEQ_OPER=drive:

    Specifies the sequence of local storage devices in which the disk-boot operation occurs. (For example, the disk0:;disk1: sequence indicates to boot from disk0: device initially and if failure occurs, boot from the disk1: device.

    BOOT_DEV_SEQ_CONF=drive:

    Indicates the configured primary and secondary devices (disk0: and disk1:) for disk mirroring. This variable is usually set by Cisco IOS XR software.

    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 router configuration file.

    IOX_CONFIG_MEDIUM=drive:path

    Permanently changes the default location where configuration files are saved.

    MIRROR_ENABLE=value

    Sets to Y in Cisco IOS XR software to indicate disk mirroring is enabled. When it is set to N, it indicates disk mirroring is disabled.

    Displaying Environment Variable Settings

    To display the current environment variable settings, enter the set command at the ROM Monitor mode prompt :

    
    rommon B1> set
    
    
    PS1=RO RSP P4D-17 ! >
    IP_ADDRESS=172.29.52.137
    DEFAULT_GATEWAY=172.29.52.1
    IP_SUBNET_MASK=255.255.255.0
    TFTP_SERVER=172.23.16.81
    IOX_ADMIN_CONFIG_FILE=
    TFTP_MGMT_INTF=0
    BOOT_DEV_SEQ_CONF=disk0:;disk1:
    MIRROR_ENABLE=Y
    ?=0
    TFTP_FILE=/auto/tftpboot-users/lpatton/comp-asr9k-mini.vm-5.2.0
    TURBOBOOT=
    BSI=0
    BOOT_DEV_SEQ_OPER=disk0:;disk1:
    BOOT=disk0:asr9k-os-mbi-5.2.0/mbiasr9k-rp.vm,1;
    ReloadReason=1
    
    

    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 ASR 9000 Series 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:

    
    rommon B1> sync
    

    Note


    Environmental values that are not saved with the sync command are discarded whenever the system is reset or booted.


    Clearing Environment Variable Settings

    To clear the environment variable settings, enter the unset command:

    
    rommon B1> unset
    

    To make the change permanent, use the sync command.


    Note


    Environmental values that are not saved with the sync command are discarded whenever the system is reset or booted.


    Viewing Chassis Serial Numbers

    The chassis serial number can be read from an RSP that is running in ROM Monitor mode. Viewing the chassis number from the RSP may be necessary if the physical label is missing or damaged.

    1. Attach a console to the console port of an RSP SC or RP in the chassis. (Only the RSP card SC or RP needs to run to perform this procedure. Other cards need not be inserted.)
    2. Apply power to the chassis.
    3. Enter ROM Monitor mode.
    4. Enter the bpcookie command in privilege mode of the ROM Monitor prompt to display the chassis serial number.
    5. Return the router to EXEC mode.

    Exiting ROM Monitor Mode

    To exit ROM Monitor mode, you must change the configuration register and reset the RSP.

    Resetting the Configuration Register Using Prompts

    To change the configuration register settings in the ROM Monitor mode, enter the confreg command at the ROM Monitor mode. Entering this command displays the configuration summary and the prompts used to change the configuration.

    In ROM Monitor mode, you can change the configuration register value using the configuration register prompts, as shown in this procedure.

    SUMMARY STEPS

      1.    confreg

      2.    Respond to each prompt as instructed.

      3.    reset


    DETAILED STEPS
       Command or ActionPurpose
      Step 1confreg


      Example:
      
      rommon B1> confreg
      
       

      Starts the configuration register configuration prompts.

       
      Step 2Respond to each prompt as instructed. 

      See the example that follows this procedure for more 
information.

       
      Step 3reset


      Example:
      
      rommon B2> reset
      
       

      Resets and initializes the router.

       

      Resetting to EXEC Mode or MBI Validation Mode

      To exit the ROM Monitor mode and reset to EXEC mode, enter the confreg command at the ROM Monitor mode prompt. Respond to prompts as instructed.

      Exiting ROM Monitor Mode: Examples

      The following example shows how to enable ROM Monitor mode at the next system boot:

      
      rommon B5 > confreg
      
      
                 Configuration Summary
         (Virtual Configuration Register: 0x1920)
      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 boot type:
       0 = ROM Monitor
       2 = MBI Validation Boot Mode
          [0]:  0
      
      
                 Configuration Summary
         (Virtual Configuration Register: 0x1920)
      enabled are:
      console baud: 9600
      boot: the ROM Monitor
      
      do you wish to change the configuration? y/n  [n]: n
      
      You must reset or power cycle for new config to take effect
      rommon B6 > reset
      

      The following example shows how to enter the minimum boot image (MBI) validation mode or the EXEC mode of Cisco IOS XR software at the next system boot:

      
      rommon B7 > confreg
      
      
                 Configuration Summary
         (Virtual Configuration Register: 0x1920)
      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 boot type:
       0 = ROM Monitor
       2 = MBI Validation Boot Mode
          [0]:  2
      
      
                 Configuration Summary
         (Virtual Configuration Register: 0x1922)
      enabled are:
      console baud: 9600
      boot: MBI Boot
      
      do you wish to change the configuration? y/n  [n]: n
      
      
      You must reset or power cycle for new config to take effect
      
      rommon B8 > reset
      

      To reset to the MBI validation mode or EXEC mode, select 2 as the boot type. Enter the reset command to boot the RSP in the EXEC mode.


      Note


      MBI validation mode causes the RSP to boot the startup Cisco IOS XR software and configuration.


      Additional References

      The following sections provide references related to the ROM Monitor.

      Related Documents

      Related Topic

      Document Title

      Connecting a terminal to a router

      Connecting and Communicating with the Router in Cisco ASR 9000 Series Aggregation Services Router Getting Started Guide

      Configuring a router with Cisco IOS XR software

      Cisco IOS XR Software Documentation:
http:/​/​www.cisco.com/​en/​US/​products/​ps5845/​tsd_​products_​support_​series_​home.html

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