Configuration files contain the Cisco IOS software commands used to customize the functionality of your Cisco switch. 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
configureterminal 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 switch, enter the
configure command 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]?
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 the showrunning-config or moresystem:running-config EXEC command. Comments are not displayed when you list the startup configuration with the showstartup-config or morenvram:startup-config EXEC mode command. Comments are stripped out of the configuration file when it is loaded onto the switch. 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 (see the “Specifying the CONFIG_FILE Environment Variable on Class A Flash File Systems” section). The CONFIG_FILE variable defaults to NVRAM and can be a file in the following file systems:
nvram: (NVRAM)
bootflash: (internal flash memory)
usbflash0: (flash file system)
Copy Configuration Files from a Network Server to the Switch
You can copy configuration files from a TFTP, rcp, or FTP server to the running configuration or
startup configuration of the switch. 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 switch. For example, you may add another switch to your network and want it to have a similar configuration to the original switch. By copying the file to the new switch, you can change the relevant parts rather than recreating the whole file.
To load the same configuration commands on to all of the switches in your network so that all of the switches have similar configurations.
The copy{ftp: | rcp: | tftp:system:running-config} EXEC command loads the configuration files into the switch as if you were typing the commands on the command line. The switch 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 is 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 is used. However, some commands in the existing configuration may not be replaced or negated. In this case, the resulting configuration file is a mixture of the existing configuration file and the copied configuration file, with the copied configuration file having precedence.
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-config command) and reload the switch.
To copy configuration files from a server to a switch, perform the tasks described in the following sections.
The protocol that 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.
Copying a Configuration File from the Switch 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.
Copying a Configuration File from the Switch to an RCP Server
You can copy a configuration file from the switch to an RCP server.
One of the first attempts to use the network as a resource in the UNIX community resulted in the design and implementation of the remote shell protocol, which included the remote shell (rsh) and remote copy (rcp) functions. Rsh and rcp give users the ability to execute commands remotely and copy files to and from a file system residing on a remote host or server on the network. The Cisco implementation of rsh and rcp interoperates with standard implementations.
The rcp copy commands rely on the rsh server (or daemon) on the remote system. To copy files using rcp, you need not create a server for file distribution, as you do with TFTP. You need only to have access to a server that supports the remote shell (rsh). (Most UNIX systems support rsh.) Because you are copying a file from one place to another, you must have read permission on the source file and write permission on the destination file. If the destination file does not exist, rcp creates it for you.
Although the Cisco rcp implementation emulates the functions of the UNIX rcp implementation—copying files among systems on the network—the Cisco command syntax differs from the UNIX rcp command syntax. The Cisco rcp support offers a set of copy commands that use rcp as the transport mechanism. These rcp copy commands are similar in style to the Cisco TFTP copy commands, but they offer an alternative that provides faster performance and reliable delivery of data. These improvements are possible because the rcp transport mechanism is built on and uses the TCP/IP stack, which is connection-oriented. You can use rcp commands to copy system images and configuration files from the switch to a network server and vice versa.
You also can enable rcp support to allow users on remote systems to copy files to and from the switch.
To configure the Cisco IOS software to allow remote users to copy files to and from the switch, use the iprcmdrcp-enable global configuration command.
The RCP protocol requires a client to send a remote username on each RCP request to a server. When you copy a configuration file from the switch to a server using RCP, the Cisco IOS software sends the first valid username it encounters in the following sequence:
The username specified in the copy EXEC command, if a username is specified.
The username set by the iprcmdremote-username global configuration command, if the command is configured.
The remote username associated with the current tty (terminal) process. For example, if the user is connected to the switch through Telnet and was authenticated through the username command, the switch software sends the Telnet username as the remote username.
The switch host name.
For the RCP copy request to execute successfully, an account must be defined on the network server for the remote username. If the server has a directory structure, the configuration file or image is written to or copied from the directory associated with the remote username on the server. For example, if the system image resides in the home directory of a user on the server, you can specify that user name as the remote username.
Use the iprcmdremote-username command to specify a username for all copies. (Rcmd is a UNIX routine used at the super-user level to execute commands on a remote machine using an authentication scheme based on reserved port numbers. Rcmd stands for “remote command”). Include the username in the copy command if you want to specify a username for that copy operation only.
If you are writing to the server, the RCP server must be properly configured to accept the RCP write request from the user on the switch. For UNIX systems, you must add an entry to the .rhosts file for the remote user on the RCP server. For example, suppose the switch contains the following configuration lines:
hostname Switch1
ip rcmd remote-username User0
If the switch IP address translates to switch1.example.com, then the .rhosts file for User0 on the RCP server should contain the following line:
Switch1.example.com Switch1
Requirements for the RCP Username
The RCP protocol requires a client to send a remote username on each RCP request to a server. When you copy a configuration file from the switch to a server using RCP, the Cisco IOS software sends the first valid username it encounters in the following sequence:
The username specified in the copy EXEC command, if a username is specified.
The username set by the iprcmdremote-username global configuration command, if the command is configured.
The remote username associated with the current tty (terminal) process. For example, if the user is connected to the switch through Telnet and is authenticated through the username command, the switch software sends the Telnet username as the remote username.
The switch host name.
For the RCP copy request to execute, an account must be defined on the network server for the remote username. If the server has a directory structure, the configuration file or image is written to or copied from the directory associated with the remote 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 RCP server for more information.
Copying a Configuration File from the Switch to an FTP Server
You can copy a configuration file from the switch to an FTP server.
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 switch to a server using FTP, the Cisco IOS software sends the first valid username it encounters in the following sequence:
The username specified in the copy EXEC command, if a username is specified.
The username set by the ip ftp username global configuration command, if the command is configured.
Anonymous.
The switch sends the first valid password it encounters in the following sequence:
The password specified in the copy command, if a password is specified.
The password set by the ip ftp password command, if the command is configured.
The switch forms a password username
@switchname.domain
. The variable username
is the username associated with the current session, switchname
is the configured host name, and domain
is the domain of the switch.
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 switch.
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.
Configuration Files Larger than NVRAM
To maintain a configuration file that exceeds the size of NVRAM, you should be aware of the information in the following sections.
The servicecompress-config global configuration command specifies that the configuration file be stored compressed in NVRAM. Once the configuration file has been compressed, the switch 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-config global configuration command works only if you have Cisco IOS software Release 10.0 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 10.0 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
Storing the Configuration in Flash Memory on Class A Flash File Systems
On class A Flash file system switches, you can store the startup configuration in flash memory by setting the CONFIG_FILE environment variable to a file in internal flash memory or flash memory in a PCMCIA slot.
Care must be taken when editing or changing a large configuration. Flash memory space is used every time a
copysystem:running-confignvram:startup-config EXEC command is issued. Because file management for flash memory (such as optimizing free space) is not done automatically, you must pay close attention to available flash memory. Use the
squeeze command to reclaim used space. We recommend that you use a large-capacity Flash card of at least 20 MB.
Loading the Configuration Commands from the Network
Configuring the Switch to Download Configuration Files
You can configure the switch 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 switch is a mixture of the original startup configuration and the one or two downloaded configuration files.
For historical reasons, the first file the switch downloads is called the network configuration file. The second file the switch downloads is called the host configuration file. Two configuration files can be used when all of the switches on a network use many of the same commands. The network configuration file contains the standard commands used to configure all of the switches. 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.
To display
information about configuration files, complete the tasks in this section:
SUMMARY STEPS
1.enable
2.showboot
3.morefile-url
4.showrunning-config
5.showstartup-config
DETAILED STEPS
Command or Action
Purpose
Step 1
enable
Example:
Switch> enable
Enables
privileged EXEC mode.
Enter your
password if prompted.
Step 2
showboot
Example:
Switch# show boot
Lists the
contents of the BOOT environment variable (if set), the name of the
configuration file pointed to by the CONFIG_FILE environment variable, and the
contents of the BOOTLDR environment variable.
Step 3
morefile-url
Example:
Switch# more 10.1.1.1
Displays the
contents of a specified file.
Step 4
showrunning-config
Example:
Switch# show running-config
Displays the
contents of the running configuration file. (Command alias for themoresystem:running-config command.)
Step 5
showstartup-config
Example:
Switch# show startup-config
Displays the
contents of the startup configuration file. (Command alias for the
morenvram: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
(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 the
show
running-config or
moresystem:running-config EXEC commands. Comments do
not display when you list the startup configuration with the
show startup-config
or
more
nvram:startup-config EXEC mode commands. Comments are stripped
out of the configuration file when it is loaded onto the
switch. 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
in privileged EXEC mode:
SUMMARY STEPS
1.enable
2.configureterminal
3.configurationcommand
4.Do one of the
following:
end
^Z
5.copysystem:running-confignvram:startup-config
DETAILED STEPS
Command or Action
Purpose
Step 1
enable
Example:
Switch> enable
Enables
privileged EXEC mode.
Enter your
password if prompted.
Step 2
configureterminal
Example:
Switch# configure terminal
Enters global
configuration mode.
Step 3
configurationcommand
Example:
Switch(config)# configuration command
Enter the
necessary configuration commands. The Cisco IOS documentation set describes
configuration commands organized by technology.
Step 4
Do one of the
following:
end
^Z
Example:
Switch(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.
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
switch prompt name of the
switch is configured. The comment line,
indicated by the exclamation mark (!), does not execute any command. The
hostname
command is used to change the
switch name from
switch to new_name. By pressing Ctrl-Z (^Z)
or entering the
end command,
the user quits configuration mode. The
copy
system:running-config
nvram:startup-config command saves the current configuration to
the startup configuration.
Switch# configure terminalSwitch(config)# !The following command provides the switch host name.Switch(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 non-default settings. The
memory is checksummed to guard against corrupted data.
Note
Some specific
commands might not get saved to NVRAM. You 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
switch after rebooting.
Copying a Configuration File
from the
Switch to a TFTP Server
(CLI)
To copy
configuration information on a TFTP network server, complete the tasks in this
section:
Copies the
startup configuration file to a TFTP server.
Examples
The following
example copies a configuration file from a
switch to a TFTP server:
Switch# 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 prompt displayed depends 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
Switch to an RCP
Server
(CLI)
To copy a startup
configuration file or a running configuration file from the
switch to an RCP server, use the following
commands beginning in privileged EXEC mode:
Storing a Running Configuration File on an RCP Server
The following example copies the running configuration file named runfile2-confg to the netadmin1 directory on the remote host with an IP address of
172.16.101.101:
Switch# copy system:running-config rcp://netadmin1@172.16.101.101/runfile2-confg
Write file runfile2-confg on host 172.16.101.101?[confirm]
Building configuration...[OK]
Connected to 172.16.101.101
Switch#
Storing a Startup Configuration File on an RCP Server
The following example shows how to store a startup configuration file on a server by using RCP to copy the file:
Switch# configure terminalSwitch(config)# ip rcmd remote-username netadmin2Switch(config)# endSwitch# copy nvram:startup-config rcp:
Remote host[]? 172.16.101.101
Name of configuration file to write [start-confg]?
Write file start-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 prompt displayed depends on how much information you provide in the copy command and the current setting of the file prompt global configuration command.
Copying a Configuration File
from the
Switch to the FTP Server
(CLI)
To copy a startup
configuration file or a running configuration file from the
switch to an FTP server, complete the
following tasks:
SUMMARY STEPS
1.enable
2.configureterminal
3.ipftpusernameusername
4.ipftppasswordpassword
5.end
6.Do one of the
following:
copysystem:running-configftp:[[[//[username [:password ]@]location]/directory ]/filename ]
or
Storing a Running Configuration File on an FTP Server
The following example copies the running configuration file named runfile-confg to the netadmin1 directory on the remote host with an IP address of
172.16.101.101:
Switch# copy system:running-config ftp://netadmin1:mypass@172.16.101.101/runfile-confg
Write file runfile-confg on host 172.16.101.101?[confirm]
Building configuration...[OK]
Connected to 172.16.101.101
Switch#
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:
Switch# configure terminalSwitch(config)# ip ftp username netadmin2Switch(config)# ip ftp password mypassSwitch(config)# endSwitch# copy nvram:startup-config ftp:
Remote host[]? 172.16.101.101
Name of configuration file to write [start-confg]?
Write file start-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 prompt displayed depends 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
Switch(CLI)
To copy a
configuration file from a TFTP server to the
switch, complete the tasks in this section:
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-confg at IP address 172.16.2.155:
Switch# 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 prompt displayed depends 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 rcp Server to the
Switch(CLI)
To copy a
configuration file from an rcp server to the running configuration or startup
configuration, complete the following tasks:
The following example copies a 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 the commands on the switch:
Switch# copy rcp://netadmin1@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]
Switch#
%SYS-5-CONFIG: Configured from host1-config by rcp from 172.16.101.101
Copy RCP 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.
Switch# configure terminalSwitch(config)# ip rcmd remote-username netadmin1Switch(config)# endSwitch# copy rcp: 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]
Switch#
%SYS-5-CONFIG_NV:Non-volatile store configured from host2-config by rcp 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 prompt displayed depends 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
Switch(CLI)
To copy a
configuration file from an FTP server to the running configuration or startup
configuration, complete the tasks in this section:
(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 3 and
4).
Step 3
ipftpusernameusername
Example:
Switch(config)# ip ftp username NetAdmin1
(Optional)
Specifies the default remote username.
Step 4
ipftppasswordpassword
Example:
Switch(config)# ip ftp password adminpassword
(Optional)
Specifies the default password.
Step 5
end
Example:
Switch(config)# end
(Optional)
Exits global configuration mode. This step is required only if you override the
default remote username or password (see Steps 3 and 4).
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 the commands on the switch:
Switch# copy ftp://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]
Switch#
%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:
Switch# configure terminalSwitch(config)# ip ftp usernamenetadmin1Switch(config)# ip ftp passwordmypassSwitch(config)# endSwitch# copy ftp: nvram:startup-config
Address of remote host [255.255.255.255]? 172.16.101.101
Name of configuration file[host1-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]
Switch#
%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 prompt displayed depends 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 the size of NVRAM, perform the tasks described in the following sections:
When you have
finished changing the running-configuration, save the new configuration.
Examples
The following
example compresses a 129-KB configuration file to 11 KB:
Switch# configure terminalSwitch(config)# service compress-configSwitch(config)# endSwitch# 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]
Switch# copy system:running-config nvram:startup-config
Building configuration...
Compressing configuration from 129648 bytes to 11077 bytes
[OK]
Storing the Configuration in
Flash Memory on Class A Flash File Systems
(CLI)
To store the
startup configuration in flash memory, complete the tasks in this section:
Use FTP, RCP, or TFTP to
copy 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]. ”
Specifies that
the startup configuration file be stored in flash memory by setting the
CONFIG_FILE variable.
Step 5
end
Example:
Switch(config)# end
Exits global
configuration mode.
Step 6
Do one of the
following:
Use FTP, RCP, or TFTP to
copy 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]. ”
Copying Configuration Files
from Flash Memory to the Startup or Running Configuration
(CLI)
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:
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 usbflash0 to the
switch startup configurations:
Switch# copy usbflash0:4:ios-upgrade-1 nvram:startup-config
Copy 'ios-upgrade-1' from flash device as 'startup-config' ? [yes/no] yes
[OK]
Copying Configuration Files
Between Flash Memory File Systems
(CLI)
On platforms with
multiple flash memory file systems, you can copy files from one flash memory
file system, such as internal flash memory to another flash memory file system.
Copying files to different flash memory file systems lets you create backup
copies of working configurations and duplicate configurations for other
switchs. To copy a configuration file
between flash memory file systems, use the following commands in EXEC mode:
Copies a
configuration file between flash memory devices.
The source
device and the destination device cannot be the same. For example, the
copyusbflash0:usbflash0: command is invalid.
Example
The following
example copies the file named running-config from partition 1 on internal flash
memory to partition 1 of usbflash0 on a
switch. In this example, the source partition
is not specified, so the
switch prompts for the partition number:
Switch# copy flash: usbflash0:
System flash
Partition Size Used Free Bank-Size State Copy Mode
1 4096K 3070K 1025K 4096K Read/Write Direct
2 16384K 1671K 14712K 8192K Read/Write Direct
[Type ?<no> for partition directory; ? for full directory; q to abort]
Which partition? [default = 1]
System flash directory, partition 1:
File Length Name/status
1 3142748 dirt/network/mars-test/c3600-j-mz.latest
2 850 running-config
[3143728 bytes used, 1050576 available, 4194304 total]
usbflash0 flash directory:
File Length Name/status
1 1711088 dirt/gate/c3600-i-mz
2 850 running-config
[1712068 bytes used, 2482236 available, 4194304 total]
Source file name? running-config
Destination file name [running-config]?
Verifying checksum for 'running-config' (file # 2)... OK
Erase flash device before writing? [confirm]
Flash contains files. Are you sure you want to erase? [confirm]
Copy 'running-config' from flash: device
as 'running-config' into usbflash0: device WITH erase? [yes/no] yes
Erasing device... eeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee ...erased!
[OK - 850/4194304 bytes]
Flash device copy took 00:00:30 [hh:mm:ss]
Verifying checksum... OK (0x16)
Copying a Configuration File
from an FTP Server to Flash Memory Devices
(CLI)
To copy a
configuration file from an FTP server to a flash memory device, complete the
task in this section:
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 prompt displayed depends 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
(CLI)
To copy a
configuration file from an RCP server to a flash memory device, complete the
tasks in this section:
Copies the
configuration file from a network server to the flash memory device using RCP.
Respond to any
switch prompts for additional information or
confirmation. Prompting depends 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
(CLI)
To copy a
configuration file from a TFTP server to a flash memory device, complete the
tasks in this section:
Copies the file
from a TFTP server to the flash memory device. Reply to any
switch prompts for additional information or
confirmation. Prompting depends on how much information you provide in the
copy command
and the current setting of the
file prompt
command.
Examples
The following
example shows the copying of the configuration file named switch-config from a
TFTP server to the flash memory card inserted in usbflash0. The copied file is
renamed new-config.
Re-executing the
Configuration Commands in the Startup Configuration File
(CLI)
To re-execute the
commands located in the startup configuration file, complete the task in this
section:
SUMMARY STEPS
1.enable
2.configurememory
DETAILED STEPS
Command or Action
Purpose
Step 1
enable
Example:
Switch> enable
Enables
privileged EXEC mode.
Enter your
password if prompted.
Step 2
configurememory
Example:
Switch# configure memory
Re-executes the
configuration commands located in the startup configuration file.
Clearing the Startup
Configuration
(CLI)
You can clear the
configuration information from the startup configuration. If you reboot the
switch with no startup configuration, the
switch enters the Setup command facility so
that you can configure the
switch from scratch. To clear the contents of
your startup configuration, complete the task in this section:
SUMMARY STEPS
1.enable
2.erasenvram
DETAILED STEPS
Command or Action
Purpose
Step 1
enable
Example:
Switch> enable
Enables
privileged EXEC mode.
Enter your
password if prompted.
Step 2
erasenvram
Example:
Switch# 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
erase startup-config
EXEC command, the
switch erases or deletes the configuration
pointed to by the CONFIG_FILE environment variable. If this variable points to
NVRAM, the
switch erases NVRAM. If the CONFIG_FILE
environment variable specifies a flash memory device and configuration
filename, the
switch deletes the configuration file. That
is, the
switch marks the file as “deleted,” rather
than erasing it. This feature allows you to recover a deleted file.
Deleting a Specified
Configuration File
(CLI)
To delete a
specified configuration on a specific flash device, complete the task in this
section:
SUMMARY STEPS
1.enable
2.deleteflash-filesystem:filename
DETAILED STEPS
Command or Action
Purpose
Step 1
enable
Example:
Switch> enable
Enables
privileged EXEC mode.
Enter your
password if prompted.
Step 2
deleteflash-filesystem:filename
Example:
Switch# delete usbflash0:myconfig
Deletes the
specified configuration file on the 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.
Specifying the CONFIG_FILE
Environment Variable on Class A Flash File Systems
(CLI)
On Class A flash
file systems, you can configure the Cisco IOS software to load the startup
configuration file specified by the CONFIG_FILE environment variable. The
CONFIG_FILE variable defaults to NVRAM. To change the CONFIG_FILE environment
variable, complete the tasks in this section:
Saves the
configuration performed in Step 3 to the startup configuration.
Step 7
showboot
Example:
Switch# show boot
(Optional)
Allows you to verify the contents of the CONFIG_FILE environment variable.
Examples
The following
example copies the running configuration file to the
switch. This configuration is then used as
the startup configuration when the system is restarted:
After you specify a location for the startup configuration file, the nvram:startup-config command is aliased to the new location of the startup configuration file. The morenvram:startup-config EXEC command displays the startup configuration, regardless of its location. The erasenvram:startup-config EXEC command erases the contents of NVRAM and deletes the file pointed to by the CONFIG_FILE environment variable.
When you save the configuration using the copysystem:running-confignvram:startup-config command, the switch saves a complete version of the configuration file to the location specified by the CONFIG_FILE environment variable and a distilled version to NVRAM. A distilled version is one that does not contain access list information. If NVRAM contains a complete configuration file, the switch prompts you to confirm your overwrite of the complete version with the distilled version. If NVRAM contains a distilled configuration, the switch does not prompt you for confirmation and proceeds with overwriting the existing distilled configuration file in NVRAM.
Note
If you specify a file in a flash device as the CONFIG_FILE environment variable, every time you save your configuration file with the copysystem:running-confignvram:startup-config command, the old configuration file is marked as “deleted,” and the new configuration file is saved to that device. Eventually, Flash memory fills up as the old configuration files still take up memory. Use the squeeze EXEC command to permanently delete the old configuration files and reclaim the space.
Configuring the Switch to Download Configuration Files
You can specify an ordered list of network configuration and host configuration filenames. The Cisco IOS XE software scans this list until it loads the appropriate network or host configuration file.
To configure the switch to download configuration files at system startup, perform at least one of the tasks described in the following sections:
If the switch fails to load a configuration file during startup, it tries again every 10 minutes (the default setting) until a host provides the requested files. With each failed attempt, the switch displays the following message on the console terminal:
Booting host-confg... [timed out]
If there are any problems with the startup configuration file, or if the configuration register is set to ignore NVRAM, the switch enters the Setup command facility.
Specifies the
network configuration file to download at startup, and the protocol to be used
(TFTP, RCP, or FTP).
If you do
not specify a network configuration filename, the Cisco IOS software uses the
default filename network-confg. If you omit the address, the
switch uses the broadcast address.
You can
specify more than one network configuration file. The software tries them in
order entered until it loads one. This procedure can be useful for keeping
files with different configuration information loaded on a network server.
Step 4
serviceconfig
Example:
Switch(config)# service config
Enables the
system to automatically load the network file on restart.
Specifies the
host configuration file to download at startup, and the protocol to be used
(FTP, RCP, or TFTP):
If you do
not specify a host configuration filename, the
switch uses its own name to form a host
configuration filename by converting the name to all lowercase letters,
removing all domain information, and appending “-confg.” If no host name
information is available, the software uses the default host configuration
filename
switch-confg. If you omit the address, the
switch uses the broadcast address.
You can
specify more than one host configuration file. The Cisco IOS software tries
them in order entered until it loads one. This procedure can be useful for
keeping files with different configuration information loaded on a network
server.
Step 4
serviceconfig
Example:
Switch(config)# service config
Enables the
system to automatically load the host file upon restart.
Saves the
running configuration to the startup configuration file.
Example
In the following
example, a
switch is configured to download the host
configuration file named hostfile1 and the network configuration file named
networkfile1. The
switch uses TFTP and the broadcast address
to obtain the file:
No new or
modified RFCs are supported, and support for existing RFCs has not been
modified.
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