Secure Copy

Last Updated: July 20, 2011

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

Finding Feature Information

Your software release may not support all the features documented in this module. For the latest feature information and caveats, see 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 document.

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 SCP, you must correctly configure SSH, authentication, and authorization on the router.
  • Because SCP relies on SSH for its secure transport, the router must have an Rivest, Shamir, and Adelman (RSA) key pair.

Information About Secure Copy

How Secure Copy Works

The behavior of SCP is similar to that of remote copy (rcp), which comes from the Berkeley r-tools suite, except that SCP relies on SSH for security. In addition, SCP requires that authentication, authorization, and accounting (AAA) authorization be configured so the router can determine whether the user has the correct privilege level.

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


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

How to Configure Secure Copy

Configuring Secure Copy

To enable and configure a Cisco router for 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.    show running-config

9.    debug ip scp


DETAILED STEPS
  Command or Action Purpose
Step 1
enable


Example:

Router> enable

 

Enables privileged EXEC mode.

  • Enter your password if prompted.
 
Step 2
configure terminal


Example:

Router# configure terminal

 

Enters global configuration mode.

 
Step 3
aaa new-model


Example:

Router(config)# aaa new-model

 

Sets AAA authentication at login.

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


Example:

Router(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:

Router(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 it when you configure SCP.
 
Step 6
username name [privilege level] {password encryption-type encrypted-password}


Example:

Router(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:

Router(config)# ip scp server enable

 

Enables SCP server-side functionality.

 
Step 8
show running-config


Example:

Router# show running-config

 

(Optional) Verifies the SCP server-side functionality.

 
Step 9
debug ip scp


Example:

Router# debug ip scp

 

(Optional) Troubleshoots SCP authentication problems.

 

Configuration Examples for Secure Copy

Example SCP Server-Side Configuration Using Local Authentication

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

! AAA authentication and authorization must be configured properly 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 ssh time-out 120
ip ssh authentication-retries 3
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 Commands List, All Releases

Secure Shell Version 1 and 2 support

  • Configuring Secure Shell module
  • Secure Shell Version 2 Support module

Authentication and authorization commands

Cisco IOS Security Command Reference

Configuring authentication and authorization

Authentication, Authorization, and Accounting (AAA) section of Cisco IOS Security Configuration Guide: Securing User Services , Release 15.0

Standards

Standards

Title

None

--

MIBs

MIBs

MIBs Link

None

To locate and download MIBs for selected platforms, Cisco software releases, and feature sets, use Cisco MIB Locator found at the following URL:

http://www.cisco.com/go/mibs

RFCs

RFCs

Title

None

--

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

12.2(2)T 12.0(21)S 12.2(25)S

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

This feature was introduced in Cisco IOS Release 12.2(2)T.

This feature was integrated into Cisco IOS Release 12.0(21)S.

This feature was integrated into Cisco IOS Release 12.2(25)S.

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

Glossary

AAA --authentication, authorization, and accounting. 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. Relying on Remote Shell (Berkeley r-tools suite) for security, rcp copies files, such as router images and startup configurations, to and from routers.

SCP --secure copy. Relying on SSH for security, SCP support allows the secure and authenticated copying of anything that exists in the Cisco IOS File System. SCP is derived from rcp.

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

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Any Internet Protocol (IP) addresses and phone numbers used in this document are not intended to be actual addresses and phone numbers. Any examples, command display output, network topology diagrams, and other figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses or phone numbers in illustrative content is unintentional and coincidental.