What is Cisco GLBP?

Gateway Load Balancing Protocol (GLBP) protects data traffic from a failed router or circuit, like Hot Standby Router Protocol (HSRP) and Virtual Router Redundancy Protocol (VRRP), while allowing packet load sharing between a group of redundant routers.

What is the purpose of GLBP?

Gateway Load Balancing Protocol (GLBP) is a Cisco proprietary protocol that attempts to overcome the limitations of existing redundant router protocols by adding basic load balancing functionality. In addition to being able to set priorities on different gateway routers, GLBP allows a weighting parameter to be set.

What type of virtualization is used in GLBP?

GLBP works by making use of a single virtual IP address, which is configured as the default gateway on the hosts. The different routers that assume the forwarding role use different virtual MAC addresses for the same virtual IP address which is used to forward packets.

What is the difference between HSRP VRRP and GLBP?

The main difference is that GLBP allows the load balancing of traffic among the master and standby routers while in HSRP (and VRRP) the standby routers do not help handle traffic. However VRRP load balancing is a proprietary implementation of VRRP and uses specific MAC addresses for that purpose.

Which load balancing algorithm is GLBP by default?

Round Robin
Round Robin is recommended as the default, it is suitable for all other requirements. Weighted can be used if there are disparities in the capabilities of gateways in the GLBP group. None provides no load balancing.

What is AVF in GLBP?

The role of the AVG is to assign a virtual MAC address to all other devices running GLBP. All devices will become an AVF (Active Virtual Forwarder) including the AVG. Whenever a computer sends an ARP Request the AVG will respond with one of the virtual MAC addresses of the available AVFs.

Is VRRP UDP or TCP?

VRRP hello packets are neither TCP nor UDP. VRRP hello packets use IP protocol number 112 where TCP uses number 6, UDP uses number 11, and ICMP uses number 1.

Is Hsrp a TCP or UDP?

HSRP is an application layer protocol. HSRP version 1 uses UDP port number 1985 and multicast address 224.0. 0.2 and version 2 uses UDP port 1985 and 224.0.

What are the features of the Cisco Catalyst 3560-e?

Combining 10/100/1000 and Power over Ethernet (PoE) configurations with 10 Gigabit Ethernet uplinks, the Cisco Catalyst 3560-E enhances worker productivity by enabling applications such as IP telephony, wireless, and video. Cisco Catalyst 3560-E Series Primary Features

How are virtual gateways elected in GLBP-Cisco?

One gateway is elected as the AVG, another gateway is elected as the standby virtual gateway, and the remaining gateways are placed in a listen state. If an AVG fails, the standby virtual gateway will assume responsibility for the virtual IP address. A new standby virtual gateway is then elected from the gateways in the listen state.

How to authenticate GLBP packets to other routers?

• Refer to the “Configuring IP Addressing” chapter of the Release 12.2 Cisco IOS IP Configuration Guide for information on configuring IP addresses. Authenticates GLBP packets received from other routers in the group. • If you configure authentication, all routers within the GLBP group must use the same authentication string.

What does GLBP stand for in Gateway load balancing protocol?