HSRP VRRP GLBP
Question 1
Which of the following MAC is a HSRP Virtual MAC address?
A. 0000.0c07.AB03
B. 0000.0c07.AD01
C. 0000.0c07.AC05
D. 0000.0c07.0001
Answer: C
Explanation
With HSRP, two or more devices support a virtual router with a fictitious MAC address and unique IP address. There are two version of HSRP.
+ With HSRP version 1, the virtual router’s MAC address is 0000.0c07.ACxx , in which xx is the HSRP group.
+ With HSRP version 2, the virtual MAC address if 0000.0C9F.Fxxx, in which xxx is the HSRP group.
Note: Another case is HSRP for IPv6, in which the MAC address range from 0005.73A0.0000 through 0005.73A0.0FFF.
-> C is correct.
(Good resource for HSRP: http://www.cisco.com/en/US/docs/switches/datacenter/sw/5_x/nx-os/unicast/configuration/guide/l3_hsrp.html)
Question 2
Which of the following statements are correct about the HSRP operation? (Choose three)
A. The HSRP master router uses the virtual IP and MAC addresses to receive traffic
B. The default hello and dead interval are 3 seconds and 10 seconds, respectively
C. HSRP gets the IP address of the active router to use as the HSRP virtual IP address
D. HSRP supports up to 255 groups per interface and we can achieve a form of load balancing via multiple groups
E. HSRP does not support md5 authentication
F. The virtual IP address of HSRP must be in a different subnet than the IP addresses of the interfaces joining that HSRP group
Answer: A B D
Explanation
For more information about HSRP operation, please read our HSRP tutorial.
Question 3
What is the main function of VRRP object tracking?
A. It analyzes traffic flow and link ultilization
B. It makes sure the best VRRP router is the virtual router master
C. Traffic will flow to the higher bandwidth links automatically
D. It enhances security for the routers
Answer: B
Explanation
Object tracking is the process of tracking the state of a configured object and uses that state to determine the priority of the VRRP router in a VRRP group -> B is correct.
Note: Unlike HSRP which can track interface status directly, VRRP can only track interface status through a tracked object.
Question 4
Which router in GLBP will responsible for responding to client ARP request?
A. Active Virtual Gateway (AVG)
B. The router with highest IP address
C. All the routers participate in GLBP group
D. Any router in the GLBP group
Answer: A
Explanation
One disadvantage of HSRP and VRRP is that only one router is in use, other routers must wait for the primary to fail because they can be used. However, Gateway Load Balancing Protocol (GLBP) can use of up to four routers simultaneously. In GLBP, there is still only one virtual IP address but each router has a different virtual MAC address. First a GLBP group must elect an Active Virtual Gateway (AVG). The AVG is responsible for replying ARP requests from hosts/clients. It replies with different virtual MAC addresses that correspond to different routers (known as Active Virtual Forwarders – AVFs) so that clients can send traffic to different routers in that GLBP group (load sharing).
Question 5
<Same as 4>
Question 6
Which of the following statements are correct about GLBP? (Choose three)
A. GLBP supports authentication with plain text and MD5 methods
B. In a GLBP group, there is one active AVG and one standby AVG
C. GLBP does not support plain text authentication
D. GLBP supports up to 1024 virtual routers per physical interface of a router
E. GLBP does not support interface tracking
F. GLBP can load balance traffic up to four routers
Answer: A D F