Secure Copy

The Secure Copy (SCP) feature provides a secure and authenticated method for copying device configurations or device image files. SCP relies on Secure Shell (SSH), an application and protocol that provide a secure replacement for the Berkeley r-tools suite (Berkeley university’s own set of networking applications). This document provides the procedure to configure a Cisco device for SCP server-side functionality.

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 at the end of this module.

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 Secure Copy

  • Before enabling Secure Copy (SCP), you must correctly configure Secure Shell (SSH), authentication, and authorization on the device.

  • Because SCP relies on SSH for its secure transport, the device must have a Rivest, Shamir, and Adelman (RSA) key pair.

Information About Secure Copy

How Secure Copy Works

The behavior of Secure Copy (SCP) is similar to that of remote copy (RCP), which comes from the Berkeley r-tools suite (Berkeley university’s own set of networking applications), except that SCP relies on Secure Shell (SSH) for security. In addition, SCP requires that authentication, authorization, and accounting (AAA) authorization be configured so that the device can determine whether the user has the correct privilege level.

SCP allows a user with appropriate authorization to copy any file that exists in the Cisco IOS File System (IFS) to and from a device by using the copy command. An authorized administrator may also perform this action from a workstation.


Note

Enable the SCP option while using the pscp.exe file with the Cisco software.

How to Configure Secure Copy

Configuring Secure Copy

To configure a Cisco device for Secure Copy (SCP) server-side functionality, perform the following steps.

SUMMARY STEPS

    1.    enable

    2.    configure terminal

    3.    aaa new-model

    4.    aaa authentication login {default | list-name} method1 [ method2... ]

    5.    aaa authorization {network | exec | commands level | reverse-access | configuration} {default | list-name} [method1 [ method2... ]]

    6.    username name [privilege level] password encryption-type encrypted-password

    7.    ip scp server enable

    8.    exit

    9.    show running-config

    10.    debug ip scp


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 aaa new-model


    Example:
    Device(config)# aaa new-model
     

    Sets AAA authentication at login.

     
    Step 4 aaa authentication login {default | list-name} method1 [ method2... ]


    Example:
    Device(config)# aaa authentication login default group tacacs+
     

    Enables the AAA access control system.

     
    Step 5 aaa authorization {network | exec | commands level | reverse-access | configuration} {default | list-name} [method1 [ method2... ]]


    Example:
    Device(config)# aaa authorization exec default group tacacs+
     

    Sets parameters that restrict user access to a network.

    Note   

    The exec keyword runs authorization to determine if the user is allowed to run an EXEC shell; therefore, you must use the exec keyword when you configure SCP.

     
    Step 6 username name [privilege level] password encryption-type encrypted-password


    Example:
    Device(config)# username superuser privilege 2 password 0 superpassword
     

    Establishes a username-based authentication system.

    Note   

    You may omit this step if a network-based authentication mechanism, such as TACACS+ or RADIUS, has been configured.

     
    Step 7 ip scp server enable


    Example:
    Device(config)# ip scp server enable
     

    Enables SCP server-side functionality.

     
    Step 8 exit


    Example:
    Device(config)# exit
     

    Exits global configuration mode and returns to privileged EXEC mode.

     
    Step 9 show running-config


    Example:
    Device# show running-config
     

    (Optional) Displays the SCP server-side functionality.

     
    Step 10 debug ip scp


    Example:
    Device# debug ip scp
     

    (Optional) Troubleshoots SCP authentication problems.

     

    Configuration Examples for Secure Copy

    Example: Secure Copy Configuration Using Local Authentication

    The following example shows how to configure the server-side functionality of Secure Copy (SCP). This example uses a locally defined username and password. 

    ! AAA authentication and authorization must be configured properly in order for SCP to work.
aaa new-model
aaa authentication login default local
aaa authorization exec default local
username user1 privilege 15 password 0 lab
! SSH must be configured and functioning properly.
ip scp server enable

    Example SCP Server-Side Configuration Using Network-Based Authentication

    The following example shows how to configure the server-side functionality of SCP using a network-based authentication mechanism:

    ! AAA authentication and authorization must be configured properly for SCP to work. 
aaa new-model 
aaa authentication login default group tacacs+
aaa authorization exec default group tacacs+
! SSH must be configured and functioning properly.
ip ssh time-out 120
ip ssh authentication-retries 3
ip scp server enable

    Additional References

    Related Documents

    Related Topic

    Document Title

    Cisco IOS commands

    Cisco IOS Master Command List, All Releases

    Secure Shell Version 1 and 2 support

    Secure Shell Configuration Guide

    Authentication and authorization commands

    Cisco IOS Security Command Reference: Commands A to C

    Configuring authentication and authorization

    Authentication, Authorization, and Accounting Configuration Guide

    Technical Assistance

    Description

    Link

    The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password.

    http:/​/​www.cisco.com/​cisco/​web/​support/​index.html

    Feature Information for Secure Copy

    The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.

    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.

    Table 1 Feature Information for Secure Copy

    Feature Name

    Releases

    Feature Information

    Secure Copy

    Cisco IOS 12.0(21)S

    Cisco IOS 12.2(2)T

    Cisco IOS 12.2(25)S

    The Secure Copy (SCP) feature provides a secure and authenticated method for copying device configurations or device image files. SCP relies on Secure Shell (SSH), an application and protocol that provide a secure replacement for the Berkeley r-tools suite.

    The following commands were introduced or modified: debug ip scp, ip scp server enable.

    Glossary

    AAA—authentication, authorization, and accounting. A framework of security services that provide the method for identifying users (authentication), for remote access control (authorization), and for collecting and sending security server information used for billing, auditing, and reporting (accounting).

    RCP—remote copy. Relies on Remote Shell (Berkeley r-tools suite) for security; RCP copies files such as device images and startup configurations to and from devices.

    SCP—secure copy. Relies on SSH for security; SCP support allows secure and authenticated copying of anything that exists in the Cisco IOS File System (IFS). SCP is derived from RCP.

    SSH—Secure Shell. An application and protocol that provide a secure replacement for the Berkeley r-tools suite. The protocol secures the sessions using standard cryptographic mechanisms, and the application can be used similar to the Berkeley rexec and rsh tools. SSH Version 1 is implemented in the Cisco software.