In the below example I will configure HRSP for VLAN 34 with a subnet of 10.204.34.0/24

Cisco Catalyst 6500 Series Switch Configuration

Step 1 – Create VLAN 34 in Cisco Catalyst Switch and assign an IP Address

MBGF-DAC-6500-BB01(config)#interface vlan 34

MBGF-DAC-6500-BB01(config-if)#ip address 10.204.34.3 255.255.255.0

Step 2 – Configure HSRP group id, priority and timers, my active switch will be Cisco 6500 Switch due to its priority

MBGF-DAC-6500-BB01(config-if)# standby 34 ip 10.204.34.1

MBGF-DAC-6500-BB01(config-if)# standby 34 timers 1 3

MBGF-DAC-6500-BB01(config-if)# standby 34 priority 150

MBGF-DAC-6500-BB01(config-if)# standby 34 preempt

Cisco Nexus 7000 Series Switch Configuration

Step 1 – Create VLAN 34 in Cisco Nexus Switch and assign an IP Address

VDC-Admin-AG01-MB-1256-002(config)# interface vlan 34

VDC-Admin-AG01-MB-1256-002(config-if)# ip address 10.204.34.2/24

Step 2 – Configure HSRP group id, priority and timers , Nexus will be in standby mode

VDC-Admin-AG01-MB-1256-002(config-if)#hsrp 34

VDC-Admin-AG01-MB-1256-002(config-if-hsrp)# priority 110

VDC-Admin-AG01-MB-1256-002(config-if-hsrp)# timers 1 3

VDC-Admin-AG01-MB-1256-002(config-if-hsrp)# ip 10.204.34.1

Verify the HSRP States

Cisco Catalyst 6500 Switch Status

MBGF-DAC-6500-BB01:1#sho standby brief

P indicates configured to preempt.

|

Interface   Grp Prio P State    Active          Standby         Virtual IP

Vl34        34  150  P Init     local           10.204.34.3         10.204.34.1

MBGF-DAC-6500-BB01:1#

Nexus 7000 Series Switch HSRP Status

VDC-Admin-AG01-MB-1256-002# sho hsrp group 34

Vlan34 – Group 34 (HSRP-V1) (IPv4)

Local state is Standby, priority 110 (Cfged 110)

Forwarding threshold(for vPC), lower: 1 upper: 110

Hellotime 1 sec, holdtime 3 sec

Next hello sent in 0.179000 sec(s)

Virtual IP address is 10.204.34.1 (Cfged)

Active router is 10.204.34.2

Standby router is local

Virtual mac address is 0000.0c07.ac22 (Default MAC)

2 state changes, last state change 2d18h

IP redundancy name is hsrp-Vlan34-34 (default)

VDC-Admin-AG01-MB-1256-002#

Configuring HRSP is a quite a simple and if you are facing any problems configuring you can post your scenario in the comments area of this post.

In my previous post I was discussing about Gateway Load Balancing Protocol (GLBP), now let’s see how Gateway Load Balancing Protocol (GLBP) does load balancing?  Basically there are three different types of Load balancing algorithms applied

Round Robin:

• This method is the default method used by Gateway Load Balancing Protocol (GLBP).
• In this method the when the client sends ARP requests to resolve the MAC- address of the default gateway , the reply contains the MAC address of the next possible router in round-robin fashion

 Weighted:

•  Gateway Load Balancing Protocol (GLBP) places a weight on each device to calculate the amount of load sharing that will occur through MAC assignment
• The routers participating in GLBP will advertise its weight and AVG will act based on that value
• For example if we have two routers named ITKE-Router A and ITKE-Router B. If the ITKE-Router A has double the bandwidth capacity then the ITKE-Router B. ITKE-Router A will be configured with the double weighting value of ITKE-Router B

Host-Dependent

• Each Client will always get the same Virtual MAC address.

• The Mac-address of the host is used to determine which AVF’s mac the host is directed towards.

• This method is used when the client needs a consistent gateway MAC -address.

• Host dependent GLBP is not recommended in situation where there are small number of hosts, for example, less than 20

In upcoming posts let’s see how to configure Gateway Load Balancing Protocol (GLBP) in Cisco devices.