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Configuring Telnet, console, and AUX portpasswords

DocumentJun 22, 2009 4:44 PM

TCC_25 years ago

Core Issue

Proper passwords protect the router from unauthorized access.

Resolution

Follow these steps to configure console passwords.

Note:Before performing this test, ensure that you have an alternate connection into the

router, such as Telnet or dial-in, in case there is a problem logging back in to the router.

1. From the privileged EXEC (enable) prompt, enter configuration mode ((config)) and

then switch to line configuration mode ((config-line), by issuing the following

commands:

Note:Notice that the prompt changes to reflect the current mode.

router#conf t

!--- Enter configuration commands, one per line. End with CNTL/Z.

router(config)#line con 0

router(config-line)#

2. Configure the password, and enable password checking at login.

router(config-line)#password

router(config-line)#login

3. Exit configuration mode.

router(config-line)#end

router#

%SYS-5-CONFIG_I: Configured from console by console

Note:Do not save your configuration changes until your ability to log in has been

verified.

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8/12/2019 Configuring Telnet

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4. Verify the configuration. Examine the configuration of the router to make sure that

the commands have been properly entered by issuing theshow running-

configcommand. To test the configuration, log off the console with the exitcommand

and log in again, using the configured password to access the router.

router#exit

router con0 is now available

Press RETURN to get started.

5. Save your configuration.

router#write memory

Perform these steps to configure Telnet passwords.

Note:Before performing this test, ensure that you have an alternate connection into the

router, such as console or dial-in, in case there is a problem logging back in to the

router.

1. From the privileged EXEC (or enable) prompt, enter configuration mode (or

(config)) and then switch to line configuration mode ((config-line)), by issuing the

following commands:

Note:Notice that the prompt changes to reflect the current mode.

router#conf t

!--- Enter configuration commands, one per line. End with CNTL/Z.

router(config)#line vty 04

router(config-line)#

2. Configure the password, and enable password checking at login.

router(config-line)#password

router(config-line)#login

3. Exit configuration mode.

router(config-line)#end

router#

%SYS-5-CONFIG_I: Configured from console by console

Note:Do not save your configuration changes until your ability to log in has been

verified.

4. Verify the configuration. Examine the configuration of the router to make sure that

the commands have been properly entered, by issuing the show running-

configcommand. Test the configuration by making a Telnet connection to the

router. This can be done by connecting from a different host on the network, but you

can also do so from the router itself by Telnetting to the IP address of any interface

http://www.cisco.com/cgi-bin/Support/Cmdlookup/ios-command-lookup.pl?type=reference&query=show+running-config&paging=25&counter=0&sa=Submithttp://www.cisco.com/cgi-bin/Support/Cmdlookup/ios-command-lookup.pl?type=reference&query=show+running-config&paging=25&counter=0&sa=Submithttp://www.cisco.com/cgi-bin/Support/Cmdlookup/ios-command-lookup.pl?type=reference&query=show+running-config&paging=25&counter=0&sa=Submithttp://www.cisco.com/cgi-bin/Support/Cmdlookup/ios-command-lookup.pl?type=reference&query=show+running-config&paging=25&counter=0&sa=Submithttp://www.cisco.com/cgi-bin/Support/Cmdlookup/ios-command-lookup.pl?type=reference&query=show+running-config&paging=25&counter=0&sa=Submithttp://www.cisco.com/cgi-bin/Support/Cmdlookup/ios-command-lookup.pl?type=reference&query=show+running-config&paging=25&counter=0&sa=Submit

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on the router that is in an up/up state as seen in the output of theshow

interfacescommand.

router#telnet

5. Save your configuration.

router#write memory

Follow these steps to configure Auxiliary (AUX) port passwords.

Note:before performing this test, ensure that you have an alternate connection into the

router, such as console or Telnet, in case there is a problem logging back in to the

router.

1. From the privileged EXEC (or enable) prompt, enter configuration mode ((config))

and then switch to line configuration mode ((config-line)), by issuing the following

commands:

Note:Notice that the prompt changes to reflect the current mode.

router#conf t

!--- Enter configuration commands, one per line. End with CNTL/Z.

router(config)#line aux 0

router(config-line)#

2. Configure the password, and enable password checking at login.

router(config-line)#password router(config-line)#login

3. Exit configuration mode.

router(config-line)#end

router#

%SYS-5-CONFIG_I: Configured from console by console

Note:Do not save your configuration changes until your ability to log in has been

verified.

4. Verify the configuration. Examine the configuration of the router to make sure thatthe commands have been properly entered by issuing the show running-

configcommand. Test the configuration by making an inbound or outbound

connection to the line. For specific information on configuring async lines for

modem connections, refer to theModem-Router Connection Guide.

5. Save your configuration.

router#write memory

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