GLBP Configuration on Cisco

Table of Contents

GLBP Cisco Configuration Example

GLBP (Gateway Load Balancing Protocol)is a Cisco Proprietary First Hop Redundancy Protocol. In this lesson, we will configure GLBP on Cisco devices with a GLBP Cisco Configuation Example. Here, you will learn How to Configure GLBP on Cisco Routers.

For our GLBP Example, we will use the below topology.

GLBP Example Topology

For GLBP Cisco Configuration, there are some steps. These steps are given below one by one:

Interface Configurations
GLBP Group Configuration with Group ID and Virtaul IP
GLBP Priority Configuration
Setting GLBP Preeption
Setting GLBP Load Balancing Option
Saving the configuration
GLBP Verification

Now, let’s start GLBP Cisco Configuation and learn How to Do GLBP Cisco Configuration practically.

Youn can also check Cisco VRRP Configuration and Cisco HSRP Configuration

Interface Configurations

Interface configuration is the basic IP configurations of switch ports. Here, our swicthes are Layer 3 switch.


Switch A# configure
Switch A(config)# interface Gigabitethernet 1/1/1
Switch A(config-if)# ip address 10.10.10.1 255.255.255.0
Switch A(config-if)# no shutdown


Switch B# configure
Switch B(config)# interface Gigabitethernet 1/1/1
Switch B(config-if)# ip address 10.10.10.2 255.255.255.0
Switch B(config-if)# no shutdown


Switch C# configure
Switch C(config)# interface Gigabitethernet 1/1/1
Switch C(config-if)# ip address 10.10.10.3 255.255.255.0
Switch C(config-if)# no shutdown

PC 1

IP : 10.10.10.14
Gw : 10.10.10.10

PC 2IP : 10.10.10.15 Gw : 10.10.10.10

Group Configuration

In this step, we will create GLBP process with GLBP Group ID and Virtual IP Address. We will do this configuration under the interfaces again. Our GLBP Group ID is 10 and our Virtual IP address is 10.10.10.10.


Switch A(config-if)# glbp 10 ip 1.10.10.10.10


Switch B(config-if)# glbp 10 ip 1.10.10.10.10


Switch C(config-if)#glbp 10 ip 1.10.10.10.10

Priority Configuration

GLBP Router roles are determined with the GLBP Priority values firsltly. If there is a tie break then the highes IP address determines the roles. Here, we will manuplate this election and give a higher GLBP Priority to Switch A. So, it will be AVG. Switch A, Switch B and Switch C will be AVF.


Switch A(config-if)# glbp 10 priority 150


Switch B(config-if)# glbp 10 priority 120


Switch C(config-if)# glbp 10 priority 100

The default GLBP Priority is 100. So, it is not necessary to configure Switch C. Here, we write it to show you only.

GLBP Example Topology

Setting GLBP Preemption

By default Preemption is off in GLBP. To open it, we wil use the below command.


Switch A(config-if)# glbp 10 preempt


Switch B(config-if)# glbp 10 preempt


Switch C(config-if)# glbp 10 preempt

Setting GLBP Load Balancing Option

There are three options for GLBP Load Balancing. These are:

Round-robin
Host-dependent
Weighted

Here, we will select the Round-robin for GLBP load balancing example. With Round-robin, traffic flow select each device orderly.


Switch A(config-if)# glbp 10 load-balancing round-robin


Switch B(config-if)# glbp 10 load-balancing round-robin


Switch C(config-if)# glbp 10 load-balancing round-robin

Saving the Configuration

The last step of configuration before the verification is saving the GLBP Cisco Configuration.


Switch A# copy running-config startup-config


Switch B# copy running-config startup-config


Switch C# copy running-config startup-config

GLBP Verification

To verify GLBP, we can use “show glbp brief” command. Beside this, you can use trace option on the PCs to see the traffic that is going through different AVFs in each time.

All First Hop Redundancy Lessons:

What is FHRP (First Hop Redundancy Protocol)? | HSRP vs VRRP vs GLBP

What is HSRP (Hot Standby Router Protocol)?

What is VRRP (Virtual Router Redundancy Protocol)?

What is GLBP (Gateway Load Balancing Protocol)?

Cisco HSRP Configuration Example

HSRP Configuration with GNS3

Cisco VRRP Configuration Example

Cisco GLBP Configuraton Example