HTTP Services Configuration Guide, Cisco IOS Release 12.2SY
HTTP 1.1 Web Server and Client
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HTTP 1.1 Web Server and Client

HTTP 1.1 Web Server and Client

Last Updated: August 17, 2011

The HTTP 1.1 Web Server and Client feature provides a consistent interface for users and applications by implementing support for HTTP 1.1 in Cisco IOS software-based devices. When combined with the HTTPS feature, the HTTP 1.1 Web Server and Client feature provides a complete, secure solution for HTTP services between Cisco devices.

This module describes the concepts and tasks related to configuring the HTTP 1.1 Web Server and Client feature.

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.

Information About the HTTP 1.1 Web Server and Client

This feature updates the Cisco implementation of HTTP from 1.0 to 1.1. The HTTP server allows features and applications, such as the Cisco web browser user interface, to be run on your routing device.

The Cisco implementation of HTTP 1.1 is backward-compatible with previous Cisco IOS releases. If you are currently using configurations that enable the HTTP server, no configuration changes are needed because all defaults remain the same.

The process of enabling and configuring the HTTP server also remains the same as in previous releases. Support for Server Side Includes (SSIs) and HTML forms has not changed. Additional configuration options, such as the ip http timeout-policy and ip http max-connections commands, have been added. These options allow configurable resource limits for the HTTP server. If you do not use these optional commands, default policies are used.

Remote applications may require that you enable the HTTP server before using them. Applications that use the HTTP server include the following:

  • The Cisco web browser user interface, which uses the Cisco IOS Homepage Server, HTTP-based EXEC Server, and HTTP IOS File System (IFS) Server.
  • The VPN Device Manager (VDM) application, which uses the VDM Server and the XML Session Manager (XSM).
  • The QoS Device Manager (QDM) application, which uses the QDM Server.
  • IP Phone and Cisco IOS Telephony Service applications, which use the ITS Local Directory Search and IOS Telephony Server (ITS).

No Cisco applications use the HTTP Client in Cisco IOS Release 12.2(15)T.

About HTTP Server General Access Policies

The ip http timeout-policy command allows you to specify general access characteristics for the server by configuring a value for idle time, connection life, and request maximum. By adjusting these values, you can configure a general policy; for example, if you want to maximize throughput for HTTP connections, you should configure a policy that minimizes the connection overhead. You can configure this type of policy by specifying large values for the life and request options so that each connection stays open longer and more requests are processed for each connection.

Another example would be to configure a policy that minimizes the response time for new connections. You can configure this type of policy by specifying small values for the life and request options so that the connections are quickly released to serve new clients.

A throughput policy would be better for HTTP sessions with dedicated management applications because it would allow the application to send more requests before the connection is closed, while a response time policy would be better for interactive HTTP sessions because it would allow more people to connect to the server at the same time without having to wait for connections to become available.

In general, you should configure these options as appropriate for your environment. The value for the idle option should be balanced; it should be large enough so as to not cause an unwanted request or response timeout on the connection and small enough so as to not hold a connection open longer than necessary.

Access security policies for the HTTP server are configured using the following commands:

  • ip http authentication—Allows only selective users to access the server.
  • ip http access-class—Allows only selective IP hosts to access the server.
  • ip http accounting commands—Specifies the command accounting method for HTTP server users.

How to Configure the HTTP 1.1 Web Server and Client

Configuring the HTTP 1.1 Web Server

Perform this task to enable the HTTP server and configure optional server characteristics. The HTTP server is disabled by default.


Note


If you want to configure authentication (step 4), you must configure the authentication type before you begin configuring the HTTP 1.1 web server.
SUMMARY STEPS

1.    enable

2.    configure terminal

3.    ip http server

4.    ip http authentication {aaa | enable | local | tacacs}

5.    ip http accounting commands level {default | named-accounting-method-list}

6.    ip http port port-number

7.    ip http path url

8.    ip http access-class access-list-number

9.    ip http max-connections value

10.    ip http timeout-policy idle seconds life seconds requests value


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
ip http server


Example:

Router(config)# ip http server

 

Enables the HTTP 1.1 server, including the Cisco web browser user interface.

Note    If you are enabling HTTP over the Secure Socket Layer (HTTPS) server using the ip http secure-server command, you should disable the standard HTTP server using the no ip http server command. This command is required to ensure only secure connections to the server.
 
Step 4
ip http authentication {aaa | enable | local | tacacs}


Example:

Router(config)# ip http authentication local

 

(Optional) Specifies the authentication method to be used for login when a client connects to the HTTP server. The methods for authentication are:

  • aaa—Indicates that the authentication method used for the authentication, authorization, and accounting (AAA) login service (specified by the aaa authentication login default command) should be used for authentication.
  • enable—Indicates that the “enable” password should be used for authentication. (This is the default method.)
  • local—Indicates that the login username, password, and privilege-level access combination specified in the local system configuration (by the username global configuration command) should be used for authentication and authorization.
  • tacacs—Indicates that the TACACS (or XTACACS) server should be used for authentication.
 
Step 5
ip http accounting commands level {default | named-accounting-method-list}


Example:

Router(config)# ip http accounting commands 15 default

 

(Optional) Specifies a particular command accounting method for HTTP server users.

  • Command accounting for HTTP and HTTPS is automatically enabled when AAA is configured on the device. It is not possible to disable accounting for HTTP and HTTPS. HTTP and HTTPS will default to using the global AAA default method list for accounting. The CLI can be used to configure HTTP and HTTPS to use any predefined AAA method list.
  • level—Valid privilege level entries are integers from 0 to 15.
  • default—Indicates the default accounting method list configured by the aaa accounting commands.
  • named-accounting-method-list—Indicates the name of the predefined command accounting method list.
 
Step 6
ip http port port-number


Example:

Router(config)# ip http port 8080

 

(Optional) Specifies the server port that should be used for HTTP communication (for example, for the Cisco web browser user interface).

 
Step 7
ip http path url


Example:

Router(config)# ip http path slot1:

 

(Optional) Sets the base HTTP path for HTML files. The base path is used to specify the location of the HTTP server files (HTML files) on the local system.

  • Generally, HTML files are located in the system flash memory.
 
Step 8
ip http access-class access-list-number


Example:

Router(config)# ip http access-class 20

 

(Optional) Specifies the access list that should be used to allow access to the HTTP server.

 
Step 9
ip http max-connections value


Example:

Router(config)# ip http max-connections 10

 

(Optional) Sets the maximum number of allowed concurrent connections to the HTTP server.

  • The default value is 5.
 
Step 10
ip http timeout-policy idle seconds life seconds requests value


Example:

Router(config)# ip http timeout-policy idle 30 life 120 requests 100

 

(Optional) Sets the characteristics that determine how long a connection to the HTTP server should remain open. The characteristics include the following:

  • idle—The maximum number of seconds the connection will be kept open if no data is received or if response data cannot be sent out on the connection. Note that a new value may not take effect on any already existing connections. If the server is too busy or the limit on the life time or the number of requests is reached, the connection may be closed sooner. The default value is 180 seconds (3 minutes).
  • life—The maximum number of seconds the connection will be kept open, from the time the connection is established. Note that the new value may not take effect on any already existing connections. If the server is too busy or the limit on the idle time or the number of requests is reached, it may close the connection sooner. Also, since the server will not close the connection while actively processing a request, the connection may remain open longer than the specified life time if processing is occurring when the life maximum is reached. In this case, the connection will be closed when processing finishes. The default value is 180 seconds (3 minutes). The maximum value is 86400 seconds (24 hours).
  • requests—The maximum limit on the number of requests processed on a persistent connection before it is closed. Note that the new value may not take effect on already existing connections. If the server is too busy or the limit on the idle time or the life time is reached, the connection may be closed before the maximum number of requests are processed. The default value is 1. The maximum value is 86400.
 

Configuring the HTTP Client

Perform this task to enable the HTTP client and configure optional client characteristics.

The standard HTTP 1.1 client and the secure HTTP client are always enabled. No commands exist to disable the HTTP client. For information about configuring optional characteristics for the HTTPS client, see the HTTPS-HTTP Server and Client with SSL 3.0 feature module.

SUMMARY STEPS

1.    enable

2.    configure terminal

3.    ip http client cache {ager interval minutes | memory {file file-size-limit | pool pool-size-limit}

4.    ip http client connection {forceclose | idle timeout seconds | retry count | timeout seconds}

5.    ip http client password password

6.    ip http client proxy-server proxy-name proxy-port port-number

7.    ip http client response timeout seconds

8.    ip http client source-interface type number

9.    ip http client username username


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
ip http client cache {ager interval minutes | memory {file file-size-limit | pool pool-size-limit}


Example:

Router(config)# ip http client cache memory file 5

 

Configures the HTTP client cache.

 
Step 4
ip http client connection {forceclose | idle timeout seconds | retry count | timeout seconds}


Example:

Router(config)# ip http client connection timeout 10

 

Configures an HTTP client connection.

 
Step 5
ip http client password password


Example:

Router(config)# ip http client password pswd1

 

Configures the default password used for connections to remote HTTP servers.

 
Step 6
ip http client proxy-server proxy-name proxy-port port-number


Example:

Router(config)# ip http client proxy-server server1 proxy-port 52

 

Configures an HTTP proxy server.

 
Step 7
ip http client response timeout seconds


Example:

Router(config)# ip http client response timeout 60

 

Specifies the timeout value, in seconds, that the HTTP client waits for a response from the server.

 
Step 8
ip http client source-interface type number


Example:

Router(config)# ip http client source-interface ethernet1/0

 

Configures a source interface for the HTTP client.

 
Step 9
ip http client username username


Example:

Router(config)# ip http client user1

 

Configures the default username used for connections to remote HTTP servers.

 

Configuration Examples for the HTTP 1.1 Web Server and Client

Example Configuring the HTTP 1.1 Web Server

The following example shows a typical configuration that enables the server and sets some characteristics:

ip http server
ip http authentication aaa
ip http accounting commands 15 default
ip http path flash:
ip access-list standard 20 
 permit 209.165.202.130 0.0.0.255 
 permit 209.165.201.1 0.0.255.255 
 permit 209.165.200.225 0.255.255.255 
! (Note: all other access implicitly denied)
 end 
ip http access-class 10
ip http max-connections 10
ip http accounting commands 1 oneacct

In the following example, a throughput timeout policy is applied. This configuration will allow each connection to be idle for a maximum of 30 seconds (approximately). Each connection will remain open (be “alive”) until either the HTTP server has been processing requests for approximately 2 minutes (120 seconds) or until approximately 100 requests have been processed.

ip http timeout-policy idle 30 life 120 requests 100 

In the following example, a Response Time timeout policy is applied. This configuration will allow each connection to be idle for a maximum of 30 seconds (approximately). Each connection will be closed as soon as the first request has been processed.

ip http timeout-policy idle 30 life 30 requests 1 

Example Verifying HTTP Connectivity

To verify remote connectivity to the HTTP server, enter the system IP address in a web browser, followed by a colon and the appropriate port number (80 is the default port number).

For example, if the system IP address is 209.165.202.129 and the port number is 8080, enter http://209.165.202.129:8080 as the URL in a web browser.

If HTTP authentication is configured, a login dialog box will appear. Enter the appropriate username and password. If the default login authentication method of “enable” is configured, you may leave the username field blank, and use the “enable” password to log in.

The system home page should appear in your browser.

Where to Go Next

For information about secure HTTP connections using Secure Sockets Layer (SSL) 3.0, refer to the HTTPS - HTTP with SSL 3.0 feature module.

Additional References

Related Documents

Related Topic

Document Title

Cisco IOS commands

Cisco IOS Master Commands List, All Releases

HTTP commands: complete command syntax, command mode, command history, defaults, usage guidelines, and examples

Cisco IOS HTTP Services Command Reference

HTTPS

  • HTTPS--HTTP with SSL 3.0 feature module
  • Firewall Support of HTTPS Authentication Proxy feature module

Standards and RFCs

Standard/RFC

Title

No specific standards are supported by this feature. Note that HTTP 1.1, as defined in RFC 2616, is currently classified as a “Standards Track” document by the IETF.

RFC 2616

Hypertext Transfer Protocol -- HTTP/1.1

The Cisco implementation of the HTTP Version 1.1 supports a subset of elements defined in RFC 2616. Following is a list of supported RFC 2616 headers:

  • Allow (Only GET, HEAD, and POST methods are supported)
  • Authorization, WWW-Authenticate - Basic authentication only
  • Cache-control
  • Chunked Transfer Encoding
  • Connection close
  • Content-Encoding
  • Content-Language
  • Content-Length
  • Content-Type
  • Date, Expires
  • Location

MIBs

MIB

MIBs Link

  • No specific MIBs are supported for this feature.

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

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 History and Information for the HTTP 1.1 Web Server and Client

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 History and Information for the HTTP 1.1 Web Server and Client

Feature Name

Releases

Feature Information

HTTP 1.1 Web Server and Client

12.2(15)T

12.2(33)SB

12.2(33)SRC

12.4(15)T

Cisco IOS XE 3.1.0SG

The HTTP 1.1 Web Server and Client feature provides a consistent interface for users and applications by implementing support for HTTP 1.1 in Cisco IOS software-based devices. When combined with the HTTPS feature, the HTTP 1.1 Web Server and Client feature provides a complete, secure solution for HTTP services between Cisco devices.

The following commands were introduced or modified by this feature: debug ip http all, debug ip http client, ip http access-class, ip http authentication, ip http client cache, ip http client connection, ip http client password, ip http client proxy-server, ip http client response timeout, ip http client source-interface, ip http client username, ip http max-connections, ip http path, ip http port, ip http server, ip http timeout-policy, show ip http client, show ip http client connection, show ip http client history, show ip http client session-module, show ip http server, show ip http server secure status.

HTTP TACACS+ Accounting Support

12.2(33)SB

12.2(33)SRC

12.2(50)SY

12.4(15)T

The HTTP TACACS+ Accounting Support feature introduces the ip http accounting commands command. This command is used to specify a particular command accounting method for HTTP server users. Command accounting provides information about commands, executed on a device, for a specified privilege level. Each command accounting record corresponds to one IOS command executed at its respective privilege level, as well as the date and time the command was executed, and the user who executed it.

The following commands were introduced or modified by this feature: ip http accounting commands.

Cisco and the Cisco Logo are trademarks of Cisco Systems, Inc. and/or its affiliates in the U.S. and other countries. A listing of Cisco's trademarks can be found at www.cisco.com/go/trademarks. Third party trademarks mentioned are the property of their respective owners. The use of the word partner does not imply a partnership relationship between Cisco and any other company. (1005R)

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.

© 2011 Cisco Systems, Inc. All rights reserved.