Table Of Contents
Management Plane Protection
First Published: February 27, 2006Last Updated: February 27, 2006
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.
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.
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)
•SSH, v1 and v2
•SNMP, all versions
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.
•IP Cisco Express Forwarding must be enabled before a management interface can be configured.
2. configure terminal
3. control-plane host
4. management-interface interface allow protocols
5. Ctrl z
6. show management-interface [interface | protocol protocol-name]
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 terminalEnter configuration commands, one per line. End with CNTL/Z.Router(config)# control-plane hostRouter(config-cp-host)# management-interface FastEthernet 0/0 allow ssh snmpRouter(config-cp-host)#.Aug 2 15:25:32.846: %CP-5-FEATURE: Management-Interface feature enabled on Control plane host pathRouter(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-interfaceManagement interface FastEthernet0/0Protocol Packets processedssh 0snmp 0Router#
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 terminalEnter configuration commands, one per line. End with CNTL/Z.Router(config)# control-plane hostRouter(config-cp-host)# management-interface GigabitEthernet 0/3 allow http ssh snmpRouter(config-cp-host)#.Aug 2 17:00:24.511: %CP-5-FEATURE: Management-Interface feature enabled on Control plane host pathRouter(config-cp-host)# management-interface GigabitEthernet 0/2 allow httpRouter(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-interfaceManagement interface GigabitEthernet0/2Protocol Packets processedhttp 0Management interface GigabitEthernet0/3Protocol Packets processedhttp 0ssh 0snmp 0
The following sections provide references related to Management Plane Protection.
Related Topic Document Title
Cisco IOS Network Management Configuration Guide
Cisco IOS Security Configuration Guide
Control Plane Policing
Control Plane Protection
No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature.
Operational Security Requirements for Large Internet Service Provider (ISP) IP Network Infrastructure
This section documents new commands only.
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 allow command in control-plane host configuration mode. To reset an interface to accept all packets, use the no form of this command.
management-interface interface allow protocols
no management-interface interface allow protocols
Interface you are configuring to be a management interface.
Network management protocols from which the interface will accept packets.
No interfaces are configured as management interfaces.
Control-plane host configuration
You can configure a management interface to accept one or many network management protocols. The following protocols are supported:
•Blocks Extensible Exchange Protocol (BEEP)
•Secure HTTP (HTTPS)
•Secure Shell (SSH), v1 and v2
•Simple Network Management Protocol (SNMP), all versions
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.
The following example shows how to enable interface FastEthernet 0/0 to accept packets from HTTP and the SSH protocol:Router(config)# control-plane hostRouter(config-cp-host)# management-interface FastEthernet0/0 allow http ssh
Displays information about the management interface, such as type of interface, protocols enabled on the interface, and number of packets dropped and processed.
To display information about management interfaces, use the show management-interface command in privileged EXEC mode.
show management-interface [interface | protocol protocol-name]
(Optional) Interface for which you want to view information.
(Optional) Indicates that a protocol is specified.
(Optional) Protocol for which you want to view information.
Information about all dedicated management interfaces is displayed when no interface or protocol is specified.
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.
The following sample output is from a show management-interface command when no interface or protocol is specified:Router# show management-interfaceManagement interface FastEthernet0/0Protocol Packets processedssh 223981
The following sample output is from a show management-interface command with interface FastEthernet 0/0 specified:Router# show management-interface fastEthernet 0/0Management interface FastEthernet0/0Protocol Packets processedssh 223981
The following sample output is from a show management-interface command with protocol Secure Shell (SSH) specified:Router# show management-interface protocol sshThe following management-interfaces allow protocol sshFastEthernet0/0 Packets processed 223981
Table 1 describes the significant fields shown in the displays.
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.
Any Internet Protocol (IP) addresses used in this document are not intended to be actual addresses. Any examples, command display output, and figures included in the document are shown for illustrative purposes only. Any use of actual IP addresses in illustrative content is unintentional and coincidental.
© 2006 Cisco Systems, Inc. All rights reserved.