Refer to the exhibit. There are two sites connected across WAN links. All intersite and intrasite
links always have the same routing metric. The network administrator sees only the top routers
and links being used by hosts at both LAN A and LAN B. What would be two suggestions to loadbalance the traffic across both WAN links? Choose two.
A.
Make HSRP track interfaces between the edge and core routers.
B.
Replace HSRP with GLBP.
C.
Add crossed intrasite links: R1-R4, R2-R3, R5-R8, and R6-R7.
D.
Make R3 and R8 have lower HSRP priority than R1 and R7.
E.
Replace HSRP with VRRP.
Explanation:
The administrator sees only the top routers (R1, R2, R5 & R7) and links being used by hosts at
both LAN A and LAN B because R1 & R7 are currently active HSRP routers (notice that all the
data will need to go through these routers). Next, all intersite and intrasite links have the same
routing metric so these active routers will send packets to R2 or R5, not R3, R4, R6 or R8 becauseof the lower metric of the top routers. For example, hosts in LAN A want to send data to hosts in
LAN B, they will send data to R1 -> R2 -> R5 -> R7, which has lower metric than the path R1 ->
R3 -> R4 -> R6 -> R5 (or R8) -> R7.
To make the network better, we should add crossed intrasite links so that R1 & R7 can send data
to both R2/R4 & R5/R6 as they have the same routing metric now -> C is correct.
Cisco Gateway Load Balancing Protocol (GLBP) differs from Cisco Hot Standby Redundancy
Protocol (HSRP) and IETF RFC 3768 Virtual Router Redundancy Protocol (VRRP) in that it has
the ability to load balance over multiple gateways. Like HSRP and VRRP an election occurs, but
rather than a single active router winning the election, GLBP elects an Active Virtual Gateway
(AVG) to assign virtual MAC addresses to each of the other GLBP routers and to assign each
network host to one of the GLBP routers -> B is correct.
Note: The routers that receive this MAC address assignment are known as Active Virtual
Forwarders (AVF).