Management Plane Protection(MPP)
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.
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.
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
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]
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 
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