Managing Configuration Files

Creating, loading, and maintaining configuration files enable you to generate a set of user-configured commands to customize the functionality of your Cisco routing device. For a complete description of the configuration file management commands, refer to the Cisco IOS Configuration Fundamentals Command Reference.

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table.

Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/​go/​cfn. An account on Cisco.com is not required.

Prerequisites for Managing Configuration Files

  • You should have at least a basic familiarity with the Cisco IOS environment and the command-line interface.

  • You should have at least a minimal configuration running on your system. You can create a basic configuration file using the setup command (see Using Setup Mode to Configure a Cisco Networking Device for details).

Restrictions for Managing Configuration Files

  • Many of the Cisco IOS commands described in this document are available and function only in certain configuration modes on the router.

Information About Managing Configuration Files

Types of Configuration Files

Configuration files contain the Cisco IOS software commands used to customize the functionality of your Cisco routing device (router, access server, switch, and so on). Commands are parsed (translated and executed) by the Cisco IOS software when the system is booted (from the startup-config file) or when you enter commands at the CLI in a configuration mode.

Startup configuration files (startup-config) are used during system startup to configure the software. Running configuration files (running-config) contain the current configuration of the software. The two configuration files can be different. For example, you may want to change the configuration for a short time period rather than permanently. In this case, you would change the running configuration using the configure terminal EXEC command but not save the configuration using the copy running-config startup-config EXEC command.

To change the running configuration, use the configure terminal command, as described in the “Modifying the Configuration File at the CLI ” section. As you use the Cisco IOS configuration modes, commands generally are executed immediately and are saved to the running configuration file either immediately after you enter them or when you exit a configuration mode.

To change the startup configuration file, you can either save the running configuration file to the startup configuration using the copy running-config startup-config EXEC command or copy a configuration file from a file server to the startup configuration (see the “Copying a Configuration File from a TFTP Server to the Router ” section for more information).

Configuration Mode and Selecting a Configuration Source

To enter configuration mode on the router, enter the configurecommand at the privileged EXEC prompt. The Cisco IOS software responds with the following prompt asking you to specify the terminal, memory, or a file stored on a network server (network) as the source of configuration commands:

Configuring from terminal, memory, or network [terminal]?

Configuring from the terminal allows you to enter configuration commands at the command line, as described in the following section. Configuring from memory loads the startup configuration file. See the “Reexecuting the Configuration Commands in the Startup Configuration File ” section for more information. Configuring from the network allows you to load and execute configuration commands over the network. See the “Copying a Configuration File from a TFTP Server to the Router ” section for more information.

Configuration File Changes Using the CLI

The Cisco IOS software accepts one configuration command per line. You can enter as many configuration commands as you want. You can add comments to a configuration file describing the commands you have entered. Precede a comment with an exclamation point ( !). Because comments are not stored in NVRAM or in the active copy of the configuration file, comments do not appear when you list the active configuration with theshow running-config or more system:running-config EXEC command. Comments do not display when you list the startup configuration with the show startup-config or more nvram:startup-config EXEC mode command. Comments are stripped out of the configuration file when it is loaded onto the router. However, you can list the comments in configuration files stored on a File Transfer Protocol (FTP), remote copy protocol (rcp), or Trivial File Transfer Protocol (TFTP) server. When you configure the software using the CLI, the software executes the commands as you enter them.

Location of Configuration Files

Configuration files are stored in the following locations:

  • The running configuration is stored in RAM.

  • On all platforms except the Class A Flash file system platforms, the startup configuration is stored in nonvolatile random-access memory (NVRAM).

  • On Class A Flash file system platforms, the startup configuration is stored in the location specified by the CONFIG_FILE environment variable. The CONFIG_FILE variable defaults to NVRAM and can be a file in the following file systems:
    • nvram: (NVRAM)

Copy Configuration Files from a Network Server to the Router

You can copy configuration files from a TFTP, rcp, or FTP server to the running configuration or startup configuration of the router. You may want to perform this function for one of the following reasons:

  • To restore a backed-up configuration file.

  • To use the configuration file for another router. For example, you may add another router to your network and want it to have a similar configuration to the original router. By copying the file to the new router, you can change the relevant parts rather than re-creating the whole file.

  • To load the same configuration commands on to all the routers in your network so that all the routers have similar configurations.

The copy{ftp: | rcp: | tftp:system:running-configEXECcommand loads the configuration files into the router as if you were typing the commands in at the command line. The router does not erase the existing running configuration before adding the commands. If a command in the copied configuration file replaces a command in the existing configuration file, the existing command will be erased. For example, if the copied configuration file contains a different IP address in a particular command than the existing configuration, the IP address in the copied configuration will be used. However, some commands in the existing configuration may not be replaced or negated. In this case, the resulting configuration file will be a mixture of the existing configuration file and the copied configuration file, with the copied configuration file having precedence.

In order to restore a configuration file to an exact copy of a file stored on a server, you need to copy the configuration file directly to the startup configuration (using the copyftp:| rcp:| tftp:} nvram:startup-configcommand) and reload the router.

To copy configuration files from a server to a router, perform the tasks described in the following sections:

The protocol you use depends on which type of server you are using. The FTP and rcp transport mechanisms provide faster performance and more reliable delivery of data than TFTP. These improvements are possible because the FTP and rcp transport mechanisms are built on and use the TCP/IP stack, which is connection-oriented.

Copy a Configuration File from the Router to a TFTP Server

In some implementations of TFTP, you must create a dummy file on the TFTP server and give it read, write, and execute permissions before copying a file over it. Refer to your TFTP documentation for more information.

Copy a Configuration File from the Router to an FTP Server

You can copy a configuration file from the router to an FTP server.

Understanding the FTP Username and Password

The FTP protocol requires a client to send a remote username and password on each FTP request to a server. When you copy a configuration file from the router to a server using FTP, the Cisco IOS software sends the first valid username it encounters in the following sequence:

  1. The username specified in the copy EXEC command, if a username is specified.

  2. The username set by the ip ftp username global configuration command, if the command is configured.

  3. Anonymous.

The router sends the first valid password it encounters in the following sequence:

  1. The password specified in the copy command, if a password is specified.

  2. The password set by the ip ftp password command, if the command is configured.

  3. The router forms a password username @routername .domain . The variable username is the username associated with the current session, routername is the configured host name, and domain is the domain of the router.

The username and password must be associated with an account on the FTP server. If you are writing to the server, the FTP server must be properly configured to accept the FTP write request from the user on the router.

If the server has a directory structure, the configuration file or image is written to or copied from the directory associated with the username on the server. For example, if the system image resides in the home directory of a user on the server, specify that user name as the remote username.

Refer to the documentation for your FTP server for more information.

Use the ip ftp username and ip ftp password global configuration commands to specify a username and password for all copies. Include the username in the copy EXEC command if you want to specify a username for that copy operation only.

Copying Files Through a VRF

You can copy files through a VRF interface specified in the copy command. Specifying the VRF in the copy command is easier and more efficient because you can directly change the source interface without having the need to change the configuration via a change request.

The following example shows how to copy files through a VRF, using the copy command:

Device# copy scp: slot0: vrf test-vrf
Device# copy scp: slot0: vrf test-vrf
Address or name of remote host [10.1.2.3]?
Source username [ScpUser]?
Source filename [/auto/tftp-server/ScpUser/vrf_test.txt]?
Destination filename [vrf_test.txt]?
Getting the vrf name as test-vrf
Password:
Sending file modes: C0644 10 vrf_test.txt
!
223 bytes copied in 22.740 secs (10 bytes/sec) 

Configuration Files Larger than NVRAM

To maintain a configuration file that exceeds size of NVRAM, you should be aware of the information in the following sections:

Compressing the Configuration File

The servicecompress-config global configuration command specifies that the configuration file be stored compressed in NVRAM. Once the configuration file has been compressed, the router functions normally. When the system is booted, it recognizes that the configuration file is compressed, expands it, and proceeds normally. The morenvram:startup-config EXEC command expands the configuration before displaying it.

Before you compress configuration files, refer to the appropriate hardware installation and maintenance publication. Verify that your system’s ROMs support file compression. If not, you can install new ROMs that support file compression.

The size of the configuration must not exceed three times the NVRAM size. For a 128-KB size NVRAM, the largest expanded configuration file size is 384 KB.

The servicecompress-configglobal configurationcommand works only if you have Cisco IOS software Release 10 or later release boot ROMs. Installing new ROMs is a one-time operation and is necessary only if you do not already have Cisco IOS Release 10 in ROM. If the boot ROMs do not recognize a compressed configuration, the following message is displayed:

Boot ROMs do not support NVRAM compression Config NOT written to NVRAM

Loading the Configuration Commands from the Network

You can also store large configurations on FTP or TFTP servers and download them at system startup. To use a network server to store large configura tions, see the “Copying a Configuration File from the Router to a TFTP Server” and “Configure the Router to Download Configuration Files” sections for more information on these commands.

Control of the Parser Cache

The Cisco IOS command-line parser in the Cisco IOS software performs the translation and execution (parsing) of command lines. The Parser Cache feature was developed to rapidly process large configuration files, thereby dramatically improving load time.

The Parser Cache feature allows the rapid recognition and translation of configuration lines in a configuration file that differ slightly from previously used configuration lines (for example, pvc 0/100, pvc 0/101, and so on) by dynamically creating, caching, and reusing simplified parse graphs. This improvement is useful primarily for configuration files that repeat similar commands hundreds or thousands of times, such as cases in which thousands of virtual circuits must be configured for subinterfaces, or hundreds of access lists must be configured. Performance will improve the most for those files in which the same commands are used repeatedly but the numerical arguments change from command to command.

The Parser Cache is enabled by default on all platforms using Cisco IOS Release 12.1(5)T and later releases. However, users with Cisco devices that do not require large configuration files may want to disable the Parser Cache to free the resources used by this feature. (Memory used by this feature depends on the size of the configuration files parsed, but is generally less than 512 KB.)

There are several ways to control the parser cache (these are all optional):

  • Clearing the Parser Cache--To free resources or to reset the parser cache memory, you may wish to clear the parse entries and hit/miss statistics stored by the Parser Cache feature

  • Disabling the Parser Cache--The Parser Cache feature is enabled by default. To disable the Parser Cache feature, use the no parser cache command in global configuration mode. When the parser cache is disabled, the noparsercache command line is written to the running configuration file. If you wish to disable the parser cache to free system resources, you should clear the parser cache before issuing the noparsercache command. You will not be able to clear the parser cache after disabling it.

  • Reenabling the Parser Cache--To reenable the Parser Cache feature after disabling it, use the parsercache command in global configuration mode

  • Monitoring the Parser--Statistics about the last configuration file parsed are kept in the system memory, along with hit/miss statistics on the commands parsed by the Parser Cache feature. “Hits” and “misses” refer to the matches that the parser cache was able to make to similar commands used previously in the configuration session. Those commands that are matched (“hits”) be parsed more efficiently. The parser cache cannot improve the parse time for those commands it was unable to match (“misses”).

Configure the Router to Download Configuration Files

You can configure the router to load one or two configuration files at system startup. The configuration files are loaded into memory and read in as if you were typing the commands at the command line. Thus, the configuration for the router will be a mixture of the original startup configuration and the one or two downloaded configuration files.

Network Versus Host Configuration Files

For historical reasons, the first file the router downloads is called the network configuration file. The second file the router downloads is called the host configuration file. Two configuration files can be used when all of the routers on a network use many of the same commands. The network configuration file contains the standard commands used to configure all of the routers. The host configuration files contain the commands specific to one particular host. If you are loading two configuration files, the host configuration file should be the configuration file you want to have precedence over the other file. Both the network and host configuration files must reside on a network server reachable via TFTP, rcp, or FTP, and must be readable.

How to Manage Configuration File Information

Displaying Configuration File Information

To display information about configuration files, complete the tasks in this section:

SUMMARY STEPS

    1.    enable

    2.    show boot

    3.    more file-url

    4.    show running-config

    5.    show startup-config


DETAILED STEPS
     Command or ActionPurpose
    Step 1 enable


    Example:
    Device> enable
     

    Enables privileged EXEC mode.

    • Enter your password if prompted.

     
    Step 2 show boot


    Example:
    Device# show boot
     

    Lists the contents of the BOOT environment variable, the name of the configuration file pointed to by the CONFIG_FILE environment variable, and the contents of the BOOTLDR environment variable.

     
    Step 3 more file-url


    Example:
    Device# more 10.1.1.1
     

    Displays the contents of a specified file.

     
    Step 4 show running-config


    Example:
    Device# show running-config
     

    Displays the contents of the running configuration file. (Command alias for the more system:running-config command.)

     
    Step 5 show startup-config


    Example:
    Device# show startup-config
     

    Displays the contents of the startup configuration file. (Command alias for the more nvram:startup-config command.)

    On all platforms except the Class A Flash file system platforms, the default startup-config file usually is stored in NVRAM. On the Class A Flash file system platforms, the CONFIG_FILE environment variable points to the default startup-config file. The CONFIG_FILE variable defaults to NVRAM.

     

    Modifying the Configuration File at the CLI

    The Cisco IOS software accepts one configuration command per line. You can enter as many configuration commands as you want. You can add comments to a configuration file describing the commands you have entered. Precede a comment with an exclamation point ( !). Because comments are not stored in NVRAM or in the active copy of the configuration file, comments do not appear when you list the active configuration with theshow running-config or more system:running-config EXEC command. Comments do not display when you list the startup configuration with the showstartup-config or more nvram:startup-config EXEC mode command. Comments are stripped out of the configuration file when it is loaded onto the router. However, you can list the comments in configuration files stored on a File Transfer Protocol (FTP), remote copy protocol (rcp), or Trivial File Transfer Protocol (TFTP) server. When you configure the software using the CLI, the software executes the commands as you enter them. To configure the software using the CLI, use the following commands beginning in privileged EXEC mode:

    SUMMARY STEPS

      1.    enable

      2.    configure terminal

      3.    Do one of the following:

      • end
      • ^Z

      4.    copy system:running-config nvram:startup-config


    DETAILED STEPS
       Command or ActionPurpose
      Step 1 enable


      Example:
      Device> enable
       

      Enables privileged EXEC mode.

      • Enter your password if prompted.

       
      Step 2 configure terminal


      Example:
      Device# configure terminal
       

      Enters global configuration mode. Enter the necessary configuration commands. The Cisco IOS documentation set describes configuration commands organized by technology.

       
      Step 3Do one of the following:
      • end
      • ^Z


      Example:
      Device(config)# end
       

      Ends the configuration session and exits to EXEC mode.

      Note   

      When you press the Ctrl and Z keys simultaneously, ^Z is displayed to the screen.

       
      Step 4 copy system:running-config nvram:startup-config


      Example:
      Device# copy system:running-config nvram:startup-config
       

      Saves the running configuration file as the startup configuration file.

      You may also use the copy running-config startup-config command alias, but you should be aware that this command is less precise. On most platforms, this command saves the configuration to NVRAM. On the Class A Flash file system platforms, this step saves the configuration to the location specified by the CONFIG_FILE environment variable (the default CONFIG_FILE variable specifies that the file should be saved to NVRAM).

       

      Examples

      In the following example, the Device prompt name of the Device is configured. The comment line, indicated by the exclamation mark (!), does not execute any command. The hostname command is used to change the Device name from Device to new_name. By pressing Ctrl-Z (^Z) or entering the endcommand, the user quits configuration mode. The copy system:running-config nvram:startup-config command saves the current configuration to the startup configuration.

      Device# configure terminal
      Device(config)# !The following command provides the Device host name.
      Device(config)# hostname new_name
      new_name(config)# end
      new_name# copy system:running-config nvram:startup-config
      

      When the startup configuration is NVRAM, it stores the current configuration information in text format as configuration commands, recording only nondefault settings. The memory is checksummed to guard against corrupted data.


      Note


      Some specific commands might not get saved to NVRAM. You will need to enter these commands again if you reboot the machine. These commands are noted in the documentation. We recommend that you keep a list of these settings so that you can quickly reconfigure your Device after rebooting.


      Copying a Configuration File from the Router to a TFTP Server

      To copy configuration information on a TFTP network server, complete the tasks in this section:

      SUMMARY STEPS

        1.    enable

        2.    copy system:running-config tftp: [[[//location ]/directory ]/filename ]

        3.    copy nvram:startup-config tftp: [[[//location ]/directory ]/filename ]


      DETAILED STEPS
         Command or ActionPurpose
        Step 1 enable


        Example:
        Device> enable
         

        Enables privileged EXEC mode.

        • Enter your password if prompted.

         
        Step 2 copy system:running-config tftp: [[[//location ]/directory ]/filename ]


        Example:
        Device# copy system:running-config tftp: //server1/topdir/file10
         

        Copies the running configuration file to a TFTP server.

         
        Step 3 copy nvram:startup-config tftp: [[[//location ]/directory ]/filename ]


        Example:
        Device# copy nvram:startup-config tftp: //server1/1stdir/file10
         

        Copies the startup configuration file to a TFTP server.

         

        Examples

        The following example copies a configuration file from a Device to a TFTP server:

        Tokyo# copy system:running-config tftp://172.16.2.155/tokyo-confg
        Write file tokyo-confg on host 172.16.2.155? [confirm] y
        Writing tokyo-confg!!! [OK]

        What to Do Next

        After you have issued the copy command, you may be prompted for additional information or for confirmation of the action. The prompting will depend on how much information you provide in the copy command and the current setting of the fileprompt global configuration command.

        Copying a Configuration File from the Router to the FTP Server

        To copy a startup configuration file or a running configuration file from the router to an FTP server, complete the following tasks:

        SUMMARY STEPS

          1.    enable

          2.    configure terminal

          3.    ip ftp username username

          4.    ip ftp password password

          5.    end

          6.    Do one of the following:

          • copy system:running-config ftp: [[[//[username [:password ]@]location/directory ]/filename ]
          • copy nvram:sta rtup-config ftp: [[[//[username [:password ]@]location/directory ]/filename ]


        DETAILED STEPS
           Command or ActionPurpose
          Step 1 enable


          Example:
          Device> enable
           

          Enables privileged EXEC mode.

          • Enter your password if prompted.

           
          Step 2 configure terminal


          Example:
          Device# configure terminal
           

          Enters global configuration mode.

           
          Step 3 ip ftp username username


          Example:
          Device(config)# ip ftp username user1
           

          (Optional) Specifies the default remote username.

           
          Step 4 ip ftp password password


          Example:
          Device(config)# ip ftp username guessme
           

          (Optional) Specifies the default password.

           
          Step 5 end


          Example:
          Device(config)# end
           

          (Optional) Exits global configuration mode. This step is required only if you override the default remote username or password (see Steps 2 and 3).

           
          Step 6Do one of the following:
          • copy system:running-config ftp: [[[//[username [:password ]@]location/directory ]/filename ]
          • copy nvram:sta rtup-config ftp: [[[//[username [:password ]@]location/directory ]/filename ]


          Example:
          Device# copy system:running-config ftp: //user1:guessme@company.com /dir10/file1
           

          Copies the running configuration or startup configuration file to an FTP server.

           

          Examples

          Storing a Running Configuration File on an FTP Server

          The following example copies the running configuration file named rtr2-confg to the netadmin1 directory on the remote host with an IP address of 172.16.101.101:

          Device# copy system:running-config ftp://netadmin1:mypass@172.16.101.101/Rtr2-confg
          Write file rtr2-confg on host 172.16.101.101?[confirm]
          Building configuration...[OK]
          Connected to 172.16.101.101
          Device#
          
          Storing a Startup Configuration File on an FTP Server

          The following example shows how to store a startup configuration file on a server by using FTP to copy the file:

          Rtr2# configure terminal
           
          Rtr2(config)# ip ftp username netadmin2
           
          Rtr2(config)# ip ftp password mypass
           
          Rtr2(config)# end
           
          Rtr2# copy nvram:startup-config ftp:
           
          Remote host[]? 172.16.101.101
           
          Name of configuration file to write [rtr2-confg]?
          Write file rtr2-confg on host 172.16.101.101?[confirm]
          ![OK]

          What to Do Next

          After you have issued the copy EXEC command, you may be prompted for additional information or for confirmation of the action. The prompting will depend on how much information you provide in the copy command and the current setting of the fileprompt global configuration command.

          Copying a Configuration File from a TFTP Server to the Router

          To copy a configuration file from a TFTP server to the Device, complete the tasks in this section:

          SUMMARY STEPS

            1.    enable

            2.    copy tftp: [[[//location ]/directory ]/filename ] system:running-config

            3.    copy tftp: [[[//location ]/directory ]/filename ] nvram:startup-config


          DETAILED STEPS
             Command or ActionPurpose
            Step 1 enable


            Example:
            Device> enable
             

            Enables privileged EXEC mode.

            • Enter your password if prompted.

             
            Step 2 copy tftp: [[[//location ]/directory ]/filename ] system:running-config


            Example:
            Device# copy tftp://server1/dir10/datasource system:running-config
             

            Copies a configuration file from a TFTP server to the running configuration.

             
            Step 3 copy tftp: [[[//location ]/directory ]/filename ] nvram:startup-config


            Example:
            Device# copy tftp://server1/dir10/datasource nvram:startup-config
             

            Copies a configuration file from a TFTP server to the startup configuration.

             

            Examples

            In the following example, the software is configured from the file named tokyo-config at IP address 172.16.2.155:

            Device1# copy tftp://172.16.2.155/tokyo-confg system:running-config
             
            Configure using tokyo-confg from 172.16.2.155? [confirm] y
             
            Booting tokyo-confg from 172.16.2.155:!!! [OK - 874/16000 bytes]

            What to Do Next

            After you have issued the copy EXEC command, you may be prompted for additional information or for confirmation of the action. The prompting will depend on how much information you provide in the copy command and the current setting of the fileprompt global configuration command.

            Copying a Configuration File from an FTP Server to the Router

            To copy a configuration file from an F TP server to the running configuration or startup configuration, complete the tasks in this section:

            SUMMARY STEPS

              1.    enable

              2.    configure terminal

              3.    ip ftp username username

              4.    ip ftp password password

              5.    end

              6.    copy ftp: [[[//[username [:password ]@]location ]/directory ]/filename ]system:running-config


            DETAILED STEPS
               Command or ActionPurpose
              Step 1 enable


              Example:
              Device> enable
               

              Enables privileged EXEC mode.

              • Enter your password if prompted.

               
              Step 2 configure terminal


              Example:
              Device# configure terminal
               

              (Optional) Allows you to enter global configuration mode. This step is required only if you want to override the default remote username or password (see Steps 2 and 3).

               
              Step 3 ip ftp username username


              Example:
              Device(config)# ip ftp username user1
               

              (Optional) Specifies the default remote username.

               
              Step 4 ip ftp password password


              Example:
              Device(config)# ip ftp password guessme
               

              (Optional) Specifies the default password.

               
              Step 5 end


              Example:
              Device(config)# end
               

              (Optional) Exits global configuration mode. This step is required only if you override the default remote username or password (see Steps 2 and 3).

               
              Step 6 copy ftp: [[[//[username [:password ]@]location ]/directory ]/filename ]system:running-config


              Example:



              Example:
              or 


              Example:
              copy ftp:[[[//[username
              [:password
              ]@]location/directory
              ]/filename
              ] nvram:startup-config


              Example:
              Device# copy ftp://user1:guessme@company.com /dir10/datasource nvram:startup-config
               

              Using FTP, copies the configuration file from a network server to running memory or the startup configuration.

               

              Examples

              Copy FTP Running-Config

              The following example copies a host configuration file named host1-confg from the netadmin1 directory on the remote server with an IP address of 172.16.101.101, and loads and runs those commands on the Device:

              Device# copy rcp://netadmin1:mypass@172.16.101.101/host1-confg system:running-config
               
              Configure using host1-confg from 172.16.101.101? [confirm]
              Connected to 172.16.101.101
              Loading 1112 byte file host1-confg:![OK]
              Device#
              %SYS-5-CONFIG: Configured from host1-config by ftp from 172.16.101.101
              Copy FTP Startup-Config

              The following example specifies a remote username of netadmin1. Then it copies the configuration file named host2-confg from the netadmin1 directory on the remote server with an IP address of 172.16.101.101 to the startup configuration.

              Rtr2# configure terminal
              Rtr2(config)# ip ftp username
               netadmin1
              Rtr2(config)# ip ftp password
               mypass
              Rtr2(config)# end
              Rtr2# copy ftp: nvram:startup-config 
              Address of remote host [255.255.255.255]? 172.16.101.101
              Name of configuration file[rtr2-confg]? host2-confg
              Configure using host2-confg from 172.16.101.101?[confirm]
              Connected to 172.16.101.101
              Loading 1112 byte file host2-confg:![OK]
              [OK]
              Rtr2#
              %SYS-5-CONFIG_NV:Non-volatile store configured from host2-config by ftp from 172.16.101.101

              What to Do Next

              After you have issued the copy EXEC command, you may be prompted for additional information or for confirmation of the action. The prompting will depend on how much information you provide in the copy command and the current setting of the fileprompt global configuration command.

              Maintaining Configuration Files Larger than NVRAM

              To maintain a configuration file that exceeds size of NVRAM, perform the tasks described in the following sections:

              Compressing the Configuration File

              To compress configuration files, complete the tasks in this section:

              SUMMARY STEPS

                1.    enable

                2.    configure terminal

                3.    service compress-config

                4.    end

                5.    Do one of the following:

                • Use FTP, rcp, or TFTP to copy the new configuration.
                • configure terminal

                6.    copy system:running-config nvram:startup-config


              DETAILED STEPS
                 Command or ActionPurpose
                Step 1 enable


                Example:
                Device> enable
                 

                Enables privileged EXEC mode.

                • Enter your password if prompted.

                 
                Step 2 configure terminal


                Example:
                Device# configure terminal
                 

                Enters global configuration mode.

                 
                Step 3 service compress-config


                Example:
                Device(config)# service compress-config
                 

                Specifies that the configuration file be compressed.

                 
                Step 4 end


                Example:
                Device(config)# end
                 

                Exits global configuration mode.

                 
                Step 5Do one of the following:
                • Use FTP, rcp, or TFTP to copy the new configuration.
                • configure terminal


                Example:
                Device# configure terminal
                 

                Enters the new configuration:

                • If you try to load a configuration that is more than three times larger than the NVRAM size, the following error message is displayed:

                “[buffer overflow - file-size /buffer-size bytes].”

                 
                Step 6 copy system:running-config nvram:startup-config


                Example:
                Device(config)# copy system:running-config nvram:startup-config
                 

                When you have finished changing the running-configuration, saves the new configuration.

                 
                Examples

                The following example compresses a 129-KB configuration file to 11 KB:

                Device# configure terminal
                 
                Device(config)# service compress-config
                 
                Device(config)# end
                 
                Device# copy tftp://172.16.2.15/tokyo-confg system:running-config
                 
                Configure using tokyo-confg from 172.16.2.155? [confirm] y
                 
                Booting tokyo-confg from 172.16.2.155:!!! [OK - 874/16000 bytes]
                Device# copy system:running-config nvram:startup-config
                 
                Building configuration...
                Compressing configuration from 129648 bytes to 11077 bytes
                [OK]
                

                Managing the Parser Cache

                To control the Parser Cache feature, perform the tasks described in the following sections. All of these tasks are optional:

                Clearing the Parser Cache

                To clear the information stored by the Parser Cache feature, complete the task in this section:

                SUMMARY STEPS

                  1.    enable

                  2.    clear parser cache


                DETAILED STEPS
                   Command or ActionPurpose
                  Step 1 enable


                  Example:
                  Device> enable
                   

                  Enables privileged EXEC mode.

                  • Enter your password if prompted.

                   
                  Step 2 clear parser cache


                  Example:
                  Device# clear parser cache
                   

                  Clears the parse cache entries and hit/miss statistics stored for the Parser Cache feature.

                   

                  Disabling the Parser Cache

                  The Parser Cache feature is enabled by default. To disable the Parser Cache feature, complete the task in this section:

                  SUMMARY STEPS

                    1.    enable

                    2.    configure terminal

                    3.    no parser cache


                  DETAILED STEPS
                     Command or ActionPurpose
                    Step 1 enable


                    Example:
                    Device> enable
                     

                    Enables privileged EXEC mode.

                    • Enter your password if prompted.

                     
                    Step 2 configure terminal


                    Example:
                    Device# configure terminal
                     

                    Enters global configuration mode.

                     
                    Step 3 no parser cache


                    Example:
                    Device(config)# no parser cache
                     

                    Disables the Parser Cache feature:

                    • When the parser cache is disabled, the noparsercache command line is written to the running configuration file.

                    • If you wish to disable the parser cache to free system resources, you should clear the parser cache before issuing the noparsercache command. You will not be able to clear the parser cache after disabling it.

                     

                    Reenabling the Parser Cache

                    To reenable the Parser Cache feature after disabling it, complete the task in this section:

                    SUMMARY STEPS

                      1.    enable

                      2.    configure terminal

                      3.    parser cache


                    DETAILED STEPS
                       Command or ActionPurpose
                      Step 1 enable


                      Example:
                      Device> enable
                       

                      Enables privileged EXEC mode.

                      • Enter your password if prompted.

                       
                      Step 2 configure terminal


                      Example:
                      Device# configure terminal
                       
                      Enters global configuration mode.  
                      Step 3 parser cache


                      Example:
                      Device(config)# parser cache
                       

                      Enables the Parser Cache feature.

                       

                      What to Do Next

                      Theshowparserstatistics command displays two sets of data, as follows:

                      • The number of commands in the configuration file that was last copied into the running configuration, and the time it took for the system to parse them (a configuration file can be loaded into the running configuration at system startup, or by issuing commands such as the copysourcerunning-config EXEC command).

                      • The status of the parser cache (enabled or disabled) and the number of command matches (hits or misses) since the system was started or since the parser cache was cleared.

                      Copying Configuration Files from Flash Memory to the Startup or Running Configuration

                      To copy a configuration file from Flash memory directly to your startup configuration in NVRAM or your running configuration, enter one of the commands in Step 2:

                      SUMMARY STEPS

                        1.    enable

                        2.    Do one of the following:

                        • copy filesystem : [partition-number:][filename ] nvram:startup-config
                        • copy filesystem : [partition-number:][filename ] system:running-config


                      DETAILED STEPS
                         Command or ActionPurpose
                        Step 1 enable


                        Example:
                        Device> enable
                         

                        Enables privileged EXEC mode.

                        • Enter your password if prompted.

                         
                        Step 2Do one of the following:
                        • copy filesystem : [partition-number:][filename ] nvram:startup-config
                        • copy filesystem : [partition-number:][filename ] system:running-config


                        Example:
                        Device# copy slot0:4:ios-upgrade-1 nvram:startup-config
                         

                        Loads a configuration file directly into NVRAM.

                        or

                        Copies a configuration file to your running configuration.

                         

                        Examples

                        The following example copies the file named ios-upgrade-1 from partition 4 of the Flash memory PC Card in slot 0 to the router startup configurations:

                        Device# copy slot0:4:ios-upgrade-1 nvram:startup-config
                         
                        Copy '
                        ios-upgrade-1
                        ' from flash device
                          as 'startup-config' ? [yes/no] yes
                         
                        [OK]

                        Copying a Configuration File from an FTP Server to Flash Memory Devices

                        To copy a configuration file from an FTP server to a Flash memory device, complete the task in this section:

                        SUMMARY STEPS

                          1.    enable

                          2.    configure terminal

                          3.    ip ftp username username

                          4.    ip ftp password password

                          5.    end

                          6.    copy ftp: [[[//[username:password@]location ]/directory ]/filename ] flash-filesystem:[partition-number:][filename ]


                        DETAILED STEPS
                           Command or ActionPurpose
                          Step 1 enable


                          Example:
                          Device> enable
                           

                          Enables privileged EXEC mode.

                          • Enter your password if prompted.

                           
                          Step 2 configure terminal


                          Example:
                          Device# configure terminal
                           

                          (Optional) Enters global configuration mode. This step is required only if you override the default remote username or password (see Steps 3 and 4).

                           
                          Step 3 ip ftp username username


                          Example:
                          Device(config)# ip ftp username user1
                           

                          (Optional) Specifies the remote username.

                           
                          Step 4 ip ftp password password


                          Example:
                          Device(config)# ip ftp password guessme
                           

                          (Optional) Specifies the remote password.

                           
                          Step 5 end


                          Example:
                          Device(config)# end
                           

                          (Optional) Exits configuration mode. This step is required only if you override the default remote username (see Steps 3 and 4).

                           
                          Step 6 copy ftp: [[[//[username:password@]location ]/directory ]/filename ] flash-filesystem:[partition-number:][filename ]


                          Example:
                          Device> copy ftp:router-config slot0:new-config
                           

                          Copies the configuration file from a network server to the Flash memory device using FTP.

                           

                          What to Do Next

                          After you have issued the copy EXEC command, you may be prompted for additional information or for confirmation of the action. The prompting will depend on how much information you provide in the copy command and the current setting of the fileprompt global configuration command.

                          Copying a Configuration File from an rcp Server to Flash Memory Devices

                          To copy a configuration file from an rcp server to a Flash memory device, complete the tasks in this section:

                          SUMMARY STEPS

                            1.    enable

                            2.    configure terminal

                            3.    ip rcmd remote-username username

                            4.    end

                            5.    copy rcp: [[[//[username@]location ]/directory ]/filename ] flash-filesystem:[partition-number:][filename ]


                          DETAILED STEPS
                             Command or ActionPurpose
                            Step 1 enable


                            Example:
                            Device> enable
                             

                            Enables privileged EXEC mode.

                            • Enter your password if prompted.

                             
                            Step 2 configure terminal


                            Example:
                            Device# configure terminal
                             

                            (Optional) Enters global configuration mode.This step is required only if you override the default remote username or password (see Steps 3 and 4).

                             
                            Step 3 ip rcmd remote-username username


                            Example:
                            Device(config)# ip rcmd remote-username user1
                             

                            (Optional) Specifies the remote username.

                             
                            Step 4 end


                            Example:
                            Device(config)# end
                             

                            (Optional) Exits configuration mode.This step is required only if you override the default remote username or password (see Steps 3 and 4).

                             
                            Step 5 copy rcp: [[[//[username@]location ]/directory ]/filename ] flash-filesystem:[partition-number:][filename ]


                            Example:
                            Device# copy rcp:router-config slot0:new-config
                             

                            Copies the configuration file from a network server to the Flash memory device using rcp. Reply to any router prompts for additional information or confirmation. The prompting will depending on how much information you provide in the copy command and the current setting of the fileprompt command.

                             

                            Copying a Configuration File from a TFTP Server to Flash Memory Devices

                            To copy a configuration file from a TFTP server to a Flash memory device, complete the task in this section:

                            SUMMARY STEPS

                              1.    enable

                              2.    copy tftp: [[[//location ]/directory ]/filename ] flash-filesystem:[partition-number:][filename ]


                            DETAILED STEPS
                               Command or ActionPurpose
                              Step 1 enable


                              Example:
                              Device> enable
                               

                              Enables privileged EXEC mode.

                              • Enter your password if prompted.

                               
                              Step 2 copy tftp: [[[//location ]/directory ]/filename ] flash-filesystem:[partition-number:][filename ]


                              Example:
                              Device# copy tftp:router-config slot0:new-config
                               

                              Copies the file from a TFTP server to the Flash memory device. Reply to any Device prompts for additional information or confirmation. The prompting will depending on how much information you provide in the copy command and the current setting of the fileprompt command.

                               

                              Examples

                              The following example shows the copying of the configuration file named Device-config from a TFTP server to the Flash memory card inserted in slot 0 of the Network Processing Engine (NPE) or Route Switch Processor (RSP) card of a Cisco 7500 series Device. The copied file is renamed new-config.

                              Device# copy tftp:router-config slot0:new-config
                              

                              Reexecuting the Configuration Commands in the Startup Configuration File

                              To reexecute the commands located in the startup configuration file, complete the task in this section:

                              SUMMARY STEPS

                                1.    enable

                                2.    configure memory


                              DETAILED STEPS
                                 Command or ActionPurpose
                                Step 1 enable


                                Example:
                                Device> enable
                                 

                                Enables privileged EXEC mode.

                                • Enter your password if prompted.

                                 
                                Step 2 configure memory


                                Example:
                                Device# configure memory
                                 

                                Reexecutes the configuration commands located in the startup configuration file .

                                 

                                Clearing the Startup Configuration

                                You can clear the configuration information from the startup configuration. If you reboot the router with no startup configuration, the router will enter the Setup command facility so that you can configure the router from scratch.To clear the contents of your startup configuration, complete the task in this section:

                                SUMMARY STEPS

                                  1.    enable

                                  2.    erase nvram


                                DETAILED STEPS
                                   Command or ActionPurpose
                                  Step 1 enable


                                  Example:
                                  Device> enable
                                   

                                  Enables privileged EXEC mode.

                                  • Enter your password if prompted.

                                   
                                  Step 2 erase nvram


                                  Example:
                                  Device# erase nvram
                                   

                                  Clears the contents of your startup configuration.

                                  Note   

                                  For all platforms except the Class A Flash file system platforms, this command erases NVRAM. The startup configuration file cannot be restored once it has been deleted. On Class A Flash file system platforms, when you use the erasestartup-configEXECcommand, the Device erases or deletes the configuration pointed to by CONFIG_FILE environment variable. If this variable points to NVRAM, the Device erases NVRAM. If the CONFIG_FILE environment variable specifies a Flash memory device and configuration filename, the Device deletes the configuration file. That is, the Device marks the file as “deleted,” rather than erasing it. This feature allows you to recover a deleted file.

                                   

                                  Deleting a Specified Configuration File

                                  To delete a specifi ed configuration on a specific Flash device, complete the task in this section:

                                  SUMMARY STEPS

                                    1.    enable

                                    2.    delete flash-filesystem : filename


                                  DETAILED STEPS
                                     Command or ActionPurpose
                                    Step 1 enable


                                    Example:
                                    Device> enable
                                     

                                    Enables privileged EXEC mode.

                                    • Enter your password if prompted.

                                     
                                    Step 2 delete flash-filesystem : filename


                                    Example:
                                    Device# delete slot0:myconfig
                                     

                                    Deletes a specified configuration file on a specified Flash device.

                                    Note   

                                    On Class A and B Flash file systems, when you delete a specific file in Flash memory, the system marks the file as deleted, allowing you to later recover a deleted file using the undelete EXEC command. Erased files cannot be recovered. To permanently erase the configuration file, use the squeeze EXEC command. On Class C Flash file systems, you cannot recover a file that has been deleted. If you attempt to erase or delete the configuration file specified by the CONFIG_FILE environment variable, the system prompts you to confirm the deletion.

                                     

                                    Additional References

                                    Related Documents

                                    Related Topic

                                    Document Title

                                    Cisco IOS commands

                                    Cisco IOS Master Command List, All Releases

                                    Cisco IOS configuration commands

                                    Cisco IOS Configuration Fundamentals Command Reference

                                    Technical Assistance

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