Saturday, 10 October 2015

Management Plane Protection


Management Plane Protection




The Management Plane Protection (MPP) feature in Cisco IOS software provides the capability to restrict the interfaces on which network management packets are allowed to enter a device. The MPP feature allows a network operator to designate one or more router interfaces as management interfaces. Device management traffic is permitted to enter a device only through these management interfaces. After MPP is enabled, no interfaces except designated management interfaces will accept network management traffic destined to the device.

Restricting management packets to designated interfaces provides greater control over management of a device, providing more security for that device. Other benefits include improved performance for data packets on nonmanagement interfaces, support for network scalability, need for fewer access control lists (ACLs) to restrict access to a device, and management packet floods on switching and routing interfaces are prevented from reaching the CPU.

Finding Feature Information in This Module

Your Cisco IOS software release may not support all of the features documented in this module. To reach links to specific feature documentation in this module and to see a list of the releases in which each feature is supported, use the "Feature Information for Management Plane Protection" section.

Finding Support Information for Platforms and Cisco IOS Software Images

Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.

Contents










Prerequisites for Management Plane Protection


IP Cisco Express Forwarding must be enabled before a management interface can be configured.

Restrictions for Management Plane Protection


Out-of-band management interfaces (also called dedicated management interfaces) are not supported. An out-of-band management interface is a dedicated Cisco IOS physical or logical interface that processes management traffic only.

Loopback and virtual interfaces not associated to physical interfaces are not supported.

Fallback and standby management interfaces are not supported.

Hardware-switched and distributed platforms are not supported.

Secure Copy (SCP) is supported under the Secure Shell (SSH) Protocol and not directly configurable in the command-line interface (CLI).

Uninformed management stations lose access to the router through nondesignated management interfaces when the Management Plane Protection feature is enabled.

Information About Management Plane Protection


Before you enable the Management Plane Protection feature, you should understand the following concepts:






In-Band Management Interface


An in-band management interface is a Cisco IOS physical or logical interface that processes management as well as data-forwarding packets. Loopback interfaces commonly are used as the primary port for network management packets. External applications communicating with a networking device direct network management requests to the loopback port. An in-band management interface is also called a shared management interface.

Control Plane Protection Overview


A control plane is a collection of processes that run at the process level on a route processor and collectively provide high-level control for most Cisco IOS software functions. All traffic directly or indirectly destined to a router is handled by the control plane.

Control Plane Policing (CoPP) is a Cisco IOS control-plane feature that offers rate limiting of all control-plane traffic. CoPP allows you to configure a quality of service (QoS) filter that manages the traffic flow of control plane packets. This QoS filter helps to protect the control plane of Cisco IOS routers and switches against denial-of-service (DoS) attacks and helps to maintain packet forwarding and protocol states during an attack or during heavy traffic loads.

Control Plane Protection is a framework that encompasses all policing and protection features in the control plane. The Control Plane Protection feature extends the policing functionality of the CoPP feature by allowing finer policing granularity. Control Plane Protection also includes a traffic classifier, which intercepts control-plane traffic and classifies it in control-plane categories. Management Plane Protection operates within the Control Plane Protection infrastructure.

For more information about the Control Plane Policing feature in Cisco IOS software, see the Control Plane Policing module.

For more information about the Control Plane Protection feature in Cisco IOS software, see the Control Plane Protection module.

Management Plane


The management plane is the logical path of all traffic related to the management of a routing platform. One of three planes in a communication architecture that is structured in layers and planes, the management plane performs management functions for a network and coordinates functions among all the planes (management, control, data). The management plane also is used to manage a device through its connection to the network.

Examples of protocols processed in the management plane are Simple Network Management Protocol (SNMP), Telnet, HTTP, Secure HTTP (HTTPS), and SSH. These management protocols are used for monitoring and for CLI access. Restricting access to devices to internal sources (trusted networks) is critical.

Management Plane Protection Feature


The MPP feature in Cisco IOS software provides the capability to restrict the interfaces on which network management packets are allowed to enter a device. The MPP feature allows a network operator to designate one or more router interfaces as management interfaces. Device management traffic is permitted to enter a device through these management interfaces. After MPP is enabled, no interfaces except designated management interfaces will accept network management traffic destined to the device. Restricting management packets to designated interfaces provides greater control over management of a device.

The MPP feature is disabled by default. When you enable the feature, you must designate one or more interfaces as management interfaces and configure the management protocols that will be allowed on those interfaces. The feature does not provide a default management interface. Using a single CLI command, you can configure, modify, or delete a management interface.When you configure a management interface, no interfaces except that management interface will accept network management packets destined to the device. When the last configured interface is deleted, the feature turns itself off.

Following are the management protocols that the MPP feature supports. These management protocols are also the only protocols affected when MPP is enabled.

Blocks Extensible Exchange Protocol (BEEP)

FTP

HTTP

HTTPS

SSH, v1 and v2

SNMP, all versions

Telnet

TFTP

Cisco IOS features enabled on management interfaces remain available when the MPP feature is enabled. Nonmanagement packets such as routing and Address Resolution Protocol (ARP) messages for in-band management interfaces are not affected.

This feature generates a syslog for the following events:

When the feature is enabled or disabled

When a management interface fails.

For example, a failure will occur when the management interface cannot successfully receive or process packets destined for the control plane for reasons other than resource exhaustion.

Benefits of the Management Plane Protection Feature


Implementing the MPP feature provides the following benefits:

Greater access control for managing a device than allowing management protocols on all interfaces

Improved performance for data packets on nonmanagement interfaces

Support for network scalability

Simplifies the task of using per-interface ACLs to restrict management access to the device

Fewer ACLs needed to restrict access to the device

Management packet floods on switching and routing interfaces are prevented from reaching the CPU

How to Configure a Device for Management Plane Protection


This section contains the following task:


Configuring a Device for Management Plane Protection


Perform this task to configure a device that you have just added to your network or a device already operating in your network. This task shows how to configure MPP where SSH and SNMP are allowed to access the router only through the FastEthernet 0/0 interface.

Prerequisites


IP Cisco Express Forwarding must be enabled before a management interface can be configured.

SUMMARY STEPS


1. enable

2. configure terminal

3. control-plane host

4. management-interface interface allow protocols

5. Ctrl z

6. show management-interface [interface | protocol protocol-name]

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 

control-plane host

Example:

Router(config)# control-plane host

Enters control-plane host configuration mode.

Step 4 

management-interfaceinterface allow protocols

Example:

Router(config-cp-host)# management-interface FastEthernet 0/0 allow ssh snmp

Configures an interface to be a management interface, which will accept management protocols, and specifies which management protocols are allowed.

interface—Name of the interface that you are designating as a management interface.

protocols—Management protocols you want to allow on the designated management interface.

BEEP

FTP

HTTP

HTTPS

SSH, v1 and v2

SNMP, all versions

Telnet

TFTP

Step 5 

Ctrl z

Example:

Router(config-cp-host)# Ctrl z

Returns to privileged EXEC mode.

Step 6 

show management-interface[interface | protocolprotocol-name]

Example:

Router# show management-interface FastEthernet 0/0

Displays information about the management interface such as type of interface, protocols enabled on the interface, and number of packets dropped and processed.

interface—(Optional) Interface for which you want to view information.

protocol—(Optional) Indicates that a protocol is specified.

protocol-name—(Optional) Protocol for which you want to view information


Examples


The configuration in this example shows MPP configured to allow SSH and SNMP to access the router only through the FastEthernet 0/0 interface. This configuration results in all protocols in the remaining subset of supported management protocols to be dropped on all interfaces unless explicitly permitted. BEEP, FTP, HTTP, HTTPS, Telnet, and TFTP will not be permitted to access the router through any interfaces, including FastEthernet 0/0. Additionally, SNMP and SSH will be dropped on all interfaces except FastEthernet 0/0, where it is explicitly allowed.

To allow other supported management protocols to access the router, you must explicitly allow these protocols by adding them to the protocol list for the FastEthernet 0/0 interface or enabling additional management interfaces and protocols.

Router# configure terminal

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

Router(config)# control-plane host

Router(config-cp-host)# management-interface FastEthernet 0/0 allow ssh snmp

Router(config-cp-host)#

.Aug  2 15:25:32.846: %CP-5-FEATURE: Management-Interface feature enabled on Control plane 
host path

Router(config-cp-host)#


The following is output from the show management-interface command issued after configuring MPP in the previous example. The show management-interface command is useful for verifying your configuration.

Router# show management-interface


Management interface FastEthernet0/0

        Protocol        Packets processed

             ssh                0

            snmp                0


Router#

Configuration Examples for Management Plane Protection


This section provides the following configuration example:


Configuring Management Plane Protection on Gigabit Ethernet Interfaces: Example


The following example shows how to configure MPP where only SSH, SNMP, and HTTP are allowed to access the router through the Gigabit Ethernet 0/3 interface and only HTTP is allowed to access the router through the Gigabit Ethernet 0/2 interface.

Router# configure terminal

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

Router(config)# control-plane host

Router(config-cp-host)# management-interface GigabitEthernet 0/3 allow http ssh snmp       

Router(config-cp-host)#

.Aug  2 17:00:24.511: %CP-5-FEATURE: Management-Interface feature enabled on Control plane 
host path

Router(config-cp-host)# management-interface GigabitEthernet 0/2 allow http

Router(config-cp-host)#


The following is output from the show management-interface command issued after configuring MPP in the previous example. The show management-interface command is useful for verifying your configuration.

Router# show management-interface 

Management interface GigabitEthernet0/2

        Protocol        Packets processed

            http                0


Management interface GigabitEthernet0/3

        Protocol        Packets processed

            http                0

             ssh                0

            snmp                0

Additional References


The following sections provide references related to Management Plane Protection.

Related Documents


Related Topic

Document Title

Network management

Cisco IOS Network Management Configuration Guide

Network security

Cisco IOS Security Configuration Guide

Control Plane Policing


Control Plane Protection



Standards


Standard

Title

No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.



MIBs


MIB

MIBs Link

No new or modified MIBs are supported by this feature, and support for existing MIBs has not been modified by this feature.

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



RFCs


RFC

Title

RFC 3871

Operational Security Requirements for Large Internet Service Provider (ISP) IP Network Infrastructure


Technical Assistance


Description

Link

The Cisco Technical Support and Documentation website contains thousands of pages of searchable technical content, including links to products, technologies, solutions, technical tips, and tools. Registered Cisco.com users can log in from this page to access even more content.



Command Reference


This section documents new commands only.

management-interface allow

show management-interface

management-interface allow


To configure an interface to be a management interface, which restricts that interface to management protocols, and to specify which management protocols are allowed, use the management-interface allowcommand in control-plane host configuration mode. To reset an interface to accept all packets, use the noform of this command.

management-interface interface allow protocols

no management-interface interface allow protocols

Syntax Description


interface

Interface you are configuring to be a management interface.

protocols

Network management protocols from which the interface will accept packets.


Command Default


No interfaces are configured as management interfaces.

Command Modes


Control-plane host configuration

Command History


Release

Modification

12.4(6)T

This command was introduced.


Usage Guidelines


You can configure a management interface to accept one or many network management protocols. The following protocols are supported:

Blocks Extensible Exchange Protocol (BEEP)

FTP

HTTP

Secure HTTP (HTTPS)

Secure Shell (SSH), v1 and v2

Simple Network Management Protocol (SNMP), all versions

Telnet

TFTP

When you configure a management interface, all incoming packets through that interface are dropped except for those from the allowed management protocols. This configuration also results in packets from all the remaining management protocols (supported in the Management Plane Protection feature) being dropped on all interfaces, including the interface you configured. The allowed management protocols are dropped by all other interfaces unless the same protocol is enabled on those interfaces.

The management-interface allow command is useful when you want to restrict access of management protocols to a device through a particular interface. An additional benefit of dedicated management interfaces is that they prevent management traffic floods on switching and routing interfaces from reaching the CPU.

Examples


The following example shows how to enable interface FastEthernet 0/0 to accept packets from HTTP and the SSH protocol:

Router(config)# control-plane host

Router(config-cp-host)# management-interface FastEthernet0/0 allow http ssh

Related Commands


Command

Description

show management-interface

Displays information about the management interface, such as type of interface, protocols enabled on the interface, and number of packets dropped and processed.



show management-interface


To display information about management interfaces, use the show management-interface command in privileged EXEC mode.

show management-interface [interface | protocol protocol-name]

Syntax Description


interface

(Optional) Interface for which you want to view information.

protocol

(Optional) Indicates that a protocol is specified.

protocol-name

(Optional) Protocol for which you want to view information.


Command Default


Information about all dedicated management interfaces is displayed when no interface or protocol is specified.

Command Modes


Privileged EXEC

Command History


Release

Modification

12.4(6)T

This command was introduced.


Usage Guidelines


The show management-interface command allows you to view all management interface configurations and activity on a device and to filter the output by interface or protocol. This flexibility is useful for network monitoring and troubleshooting.

Examples


The following sample output is from a show management-interface command when no interface or protocol is specified:

Router# show management-interface


Management interface FastEthernet0/0

        Protocol        Packets processed

             ssh                223981


The following sample output is from a show management-interface command with interfaceFastEthernet 0/0 specified:

Router# show management-interface fastEthernet 0/0


Management interface FastEthernet0/0

        Protocol        Packets processed

             ssh                223981


The following sample output is from a show management-interface command with protocol Secure Shell (SSH) specified:

Router# show management-interface protocol ssh


The following management-interfaces allow protocol ssh

        FastEthernet0/0 Packets processed 223981


Table 1 describes the significant fields shown in the displays.

Table 1 show management-interface Field Descriptions 

Field

Description

Management interface <interface>

Interface designated as a management interface.

Protocol

Network management protocols enabled on the interface.

Packets processed

The number of packets processesd on the interface.


Related Commands


Command

Description

management-interface allow

Configures an interface to accept only network management packets.


Feature Information for Management Plane Protection


Table 2 lists the release history for this feature.

Not all commands may be available in your Cisco IOS software release. For release information about a specific command, see the command reference documentation.

Cisco IOS software images are specific to a Cisco IOS software release, a feature set, and a platform. Use Cisco Feature Navigator to find information about platform support and Cisco IOS software image support. Access Cisco Feature Navigator at http://www.cisco.com/go/fn. You must have an account on Cisco.com. If you do not have an account or have forgotten your username or password, click Cancel at the login dialog box and follow the instructions that appear.


Note Table 2 lists only the Cisco IOS software release that introduced support for a given feature in a given Cisco IOS software release train. Unless noted otherwise, subsequent releases of that Cisco IOS software release train also support that feature.


Table 2 Feature Information for Management Plane Protection 

Feature Name

Releases

Feature Information

Management Plane Protection

12.4(6)T

Provides the capability to restrict the interfaces on which network management packets are allowed to enter a device.