Table Of Contents

Configuring the MNLB Forwarding Agent

Configuration Tasks

Enabling Cisco Express Forwarding

Enabling NetFlow Switching

Enabling Multicast Routing

Configuring the Router as a Forwarding Agent

Monitoring the Forwarding Agent

Configuration Examples

3

Configuring the MNLB Forwarding Agent

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This chapter describes how to configure a Cisco router as an MNLB Forwarding Agent to operate in conjunction with a Cisco LocalDirector serving as Services Manager

The components of the MNLD Feature Set for LocalDirector are described in Chapter 1, " Overview: Load Balancing with the MNLB Feature Set for LocalDirector".

Configuration Tasks

The following sections describe forwarding agent configuration tasks.

• Enabling Cisco Express Forwarding

• Enabling NetFlow Switching

• Enabling Multicast Routing

• Configuring the Router as a Forwarding Agent

Enabling Cisco Express Forwarding

Cisco Express Forwarding (CEF) is advanced Layer 3 IP switching technology. CEF optimizes network performance and scalability for networks with large and dynamic traffic patterns, such as the Internet, on networks characterized by intensive Web-based applications, or interactive sessions.

To enable CEF, use the following command in global configuration mode:

Command	Purpose
Router(config) ip cef distributed	Enables CEF.

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Note   When you enable CEF globally, all interfaces that support CEF are enabled by default. If you want to turn off CEF on a particular interface, you can do so.

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Enabling NetFlow Switching

We recommend that you enable NetFlow switching on all interfaces that will carry MNLB traffic, although it is not required. To enable NetFlow switching, use the following commands, beginning in global configuration mode:

Step	Command	Purpose
1	For VIP interfaces on Cisco 7500 series routers: Router(config)# interface type slot/port-adapter/port For all other routers: Router(config)# interface type slot/port	Specifies the interface, and enters interface configuration mode.
2	Router(config-if)# ip route-cache flow	Enables flow switching on the interface.

Normally the size of the NetFlow cache will meet your needs. However, you can increase or decrease the number of entries maintained in the cache by using the following command in global configuration mode

Command	Purpose
Router(config)# ip flow-cache entries number	Changes the number of entries maintained in the NetFlow cache. The number of entries can be 1024 to 524288. The default is 64536.

Enabling Multicast Routing

You must enable multicast routing on all interfaces to the services manager.

To enable multicast routing on all interfaces, use the following command in global configuration mode:

Command	Purpose
Router(config)# ip multicast-routing	Enables multicast routing.

To have the router join a multicast group and enable IGMP, use the following command in interface configuration mode:

Command	Purpose
Router(config-if)# ip igmp join-group1 group-address2	Joins a multicast group.

1 This command must be configured on all interfaces that will listen for the services manager multicasts. 2 The group address must match that configured within the services manager configuration.

Configuring the Router as a Forwarding Agent

To configure the router as a forwarding agent, use the following commands, beginning in global configuration mode:

Step	Command	Purpose
1	Router(config)# ip casa control-address igmp-address	Specify the control address and IGMP address of the forwarding agent. The control address is a unique ip address used by forwarding-agent to send and receive control message between the service manager and the forwarding-agent. The recommended IGMP address is 224.0.1.2.
2	Router(config) forwarding-agent pool [initial-affinity] [max-affinity]	Adjusts the memory allocated for the forwarding agent's affinity pools. The default pool size is 5000 and there is no maximum pool size.
3	Router(config) forwarding-agent num [passwd [timeout]]	Specify the port number.

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Note   The forwarding agent IGMP address and port must match the IGMP address and port configured on the services manager and the ip igmp join-group command.

If you are running CASA, you must configure ip pim dense. Some Forwarding Agents might be many hops away, so TTL=1 might not work in some cases.

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Monitoring the Forwarding Agent

To monitor the status of the forwarding agent, use the following commands in EXEC mode:

Command	Purpose
Router# show ip casa affinities	Display the status of affinities.
Router# show ip casa oper	Display the operational status of the forwarding agent.
Router# show ip casa stats	Display statistical information about the forwarding agent.
Router# show ip casa wildcard	Display information about wildcard blocks.

Configuration Examples

This section provides the following configuration examples:

• Forwarding Agent Configuration for FA2

• Services Manager Configuration for SM

The network configured is shown in .

Figure 2 MultiNode Load Balancing Network Configuration

Forwarding Agent Configuration for FA2

In the following example all disabled interfaces have been omitted to simplify the display.

FA2#wr t

Building configuration...




Current configuration:

!

version 12.0

service timestamps debug uptime

service timestamps log uptime

no service password-encryption

service udp-small-servers

service tcp-small-servers

!

hostname FA2

!

!

microcode CIP flash slot0:cip26-5

microcode reload

ip subnet-zero

no ip domain-lookup

!

ip cef distributed

ip casa 206.10.20.34 224.0.1.2

forwarding-agent 1637

!

interface Ethernet0/0

ip address 172.26.56.18 255.255.255.224

no ip directed-broadcast

ip route-cache flow

ip igmp join-group 224.0.1.2

no ip mroute-cache

!

interface Ethernet0/1

ip address 172.26.56.37 255.255.255.224

no ip directed-broadcast

!

!

!

router eigrp 777

network 172.26.0.0

!




no ip classless

!

line con 0

exec-timeout 0 0

transport input none

line aux 0

line vty 0 4

exec-timeout 0 0

login

!

end

Services Manager Configuration for SM

SM# wr t

Building configuration...

: Saved

: LocalDirector 420 Version 3.0.0.127

syslog output 20.3

no syslog console

enable password 000000000000000000000000000000 encrypted

hostname SM

no shutdown ethernet 0

no shutdown ethernet 1

no shutdown ethernet 2

no shutdown ethernet 3

interface ethernet 0 auto

interface ethernet 1 auto

interface ethernet 2 auto

interface ethernet 3 auto

mtu 0 1500

mtu 1 1500

mtu 2 1500

mtu 3 1500

multiring all

no secure 0

no secure 1

no secure 2

no secure 3

ping-allow 0

ping-allow 1

ping-allow 2

ping-allow 3

ip address 172.26.56.19 255.255.255.248

route 172.26.10.249 255.255.255.255 172.26.56.20 1

route 206.10.20.33 255.255.255.255 172.26.56.17 1

route 206.10.20.34 255.255.255.255 172.26.56.18 1

no rip passive

failover ip address 0.0.0.0

failover

password cisco

telnet 161.0.0.0 255.0.0.0

no snmp-server contact

no snmp-server location

casa service-manager port 1638

casa service-manager multicast-ttl 60

tftp-server 172.26.10.249 /tftpboot/LD

virtual 172.26.56.13:0:0:tcp is

virtual 172.26.56.2:0:0:tcp is

redirection 172.26.56.13:0:0:tcp dispatched casa wildcard-ttl 60 fixed-ttl 60 igmp 224.0.1.2 port 1637

redirection 172.26.56.2:0:0:tcp dispatched casa wildcard-ttl 60 fixed-ttl 60 igmp 224.0.1.2 port 1637

real 172.26.56.34:0:0:tcp is

real 172.26.56.33:0:0:tcp is

real 172.26.56.6:0:0:tcp is

real 172.26.56.10:0:0:tcp is

bind 172.26.56.13:0:0:tcp 172.26.56.33:0:0:tcp

bind 172.26.56.13:0:0:tcp 172.26.56.34:0:0:tcp

bind 172.26.56.2:0:0:tcp 172.26.56.10:0:0:tcp

bind 172.26.56.2:0:0:tcp 172.26.56.6:0:0:tcp

: end

Posted: Mon Jun 20 12:57:25 PDT 2005
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