All Cisco-Network Study Notes: HSRP Status

HSRP Status

To affectation the cachet of the HSRP router, admission the afterward command in advantaged EXEC

mode.

Router#show standby type-number accumulation brief

The command options for this command are authentic as follows:

• type-number—This alternative altercation indicates the ambition interface blazon and cardinal for

which achievement is displayed.

• group—This alternative altercation indicates a specific HSRP accumulation on the interface for

which achievement is displayed.

• brief—This advantage displays a distinct band of achievement summarizing anniversary standby group.

If these alternative interface ambit are not indicated, the appearance standby command displays

HSRP advice for all interfaces. Example 9-5 presents the achievement consistent back the typenumber

and accumulation ambit are specified.

Example 9-6 demonstrates achievement consistent back the abrupt constant is specified.

Troubleshooting HSRP

The Cisco IOS accomplishing of HSRP supports the alter command. Enabling debug

displays the HSRP accompaniment changes and debugging advice apropos manual and receipt

of HSRP packets. To accredit HSRP debugging, admission the afterward command in privileged

EXEC mode:

Router#debug standby

Example 9-5 appearance standby Command Achievement with type-number and accumulation Ambit Specified

Router#show standby Vlan100 50

Vlan100 - Accumulation 50

Local accompaniment is Active, antecedence 150, may preempt

Hellotime 3 holdtime 10

Next accost beatific in 00:00:02.944

Hot standby IP abode is 192.168.100.50 configured

Active router is local

Standby router is 192.168.100.1 expires in 00:00:08

Standby basal mac abode is 0000.0d05.ab10

Tracking interface states for 1 interface, 1 up:

Up Vlan51 Antecedence decrement: 40

Example 9-6 appearance standby abrupt Command Output

Router#show standby brief

Interface Grp Prio P Accompaniment Alive addr Standby addr Accumulation addr

Vl00 50 160 P Alive bounded 192.168.100.1 192.168.100.50

Vl12 12 100 Standby 192.168.102.1 bounded 192.168.12.10

324 Affiliate 9: Overview of Hot Standby Router Protocol

CAUTION Activating the alter command can account your arrangement to be abstract due to the aerial priority

assigned to this action in the CPU. Use with caution!

Example 9-7 displays the alter standby command achievement as the router with the IP address

192.168.100.1 initializes and negotiates for the role of the alive router.

The achievement of this alter command shows the assorted states of HSRP. The states are initial,

listen, learn, speak, standby, and active. In the end, VLAN100 is in an alive state.

To attenuate the debugging feature, admission either the no alter standby command or the no debug

all command. You may additionally use undebug standby or undebug all.

Example 9-7 alter standby Command Output

3w1d : %STANDBY-6-STATECHANGE: Standby: 0: Vlan100 accompaniment Init -> Listen

3w1d : %STANDBY-6-STATECHANGE: Standby: 0: Vlan100 accompaniment Listen -> Speak

3w1d : SB0:Vlan100 Accost out 192.168.100.1 Allege pri 160 hel 3 hol 10 ip

192.168.100.50

3w1d : SB0:Vlan100 Accost out 192.168.100.1 Allege pri 160 hel 3 hol 10 ip

192.168.100.50

3w1d : SB0:Vlan100 Accost out 192.168.100.1 Allege pri 160 hel 3 hol 10 ip

192.168.100.50

3w1d : SB0:Vlan100 Accost out 192.168.100.1 Allege pri 160 hel 3 hol 10 ip

192.168.100.50

3w1d : %STANDBY-6-STATECHANGE: Standby: 0: Vlan100 accompaniment Allege -> Standby

3w1d : %STANDBY-6-STATECHANGE: Standby: 0: Vlan100 accompaniment Standby -> Active

3w1d : SB: Vlan100 Abacus 0000.0d05.ab10 to abode filter

Q&A 325

Q&A

The questions and scenarios in this book are added difficult than what you should acquaintance on

the absolute exam. The questions do not attack to awning added across or abyss than the exam;

however, they are advised to accomplish abiding that you apperceive the answer. Rather than acceptance you

to acquire the acknowledgment from clues hidden central the catechism itself, the questions claiming your

understanding and anamnesis of the subject. Questions from the “Do I Apperceive This Already?” quiz

from the alpha of the affiliate are afresh actuality to ensure that you accept baffled the

chapter’s affair areas. Hopefully, these questions will advice absolute the cardinal of assay questions

on which you attenuated your choices to two options and afresh guess.

The answers to these questions can be begin in Appendix A, on folio 477.

1 What is the name of the agreement that allows a set of routers that are alive calm to

form one basal router?

_______________________________________________________________________

2 What botheration makes HSRP necessary?

_______________________________________________________________________

3 What is the minimum cardinal of routers bare to accomplish HSRP?

_______________________________________________________________________

4 What is the RFC that pertains to HSRP?

_______________________________________________________________________

5 In a appropriately activity basal router, what happens back one of the routers fails?

_______________________________________________________________________

326 Affiliate 9: Overview of Hot Standby Router Protocol

6 How abounding standby groups can abide on any one LAN?

______________________________________________________________________

7 What constitutes an HSRP group?

______________________________________________________________________

8 What is the role of the alive router?

______________________________________________________________________

9 Name the six states that an HSRP configured router can be in.

______________________________________________________________________

10 Back configuring HSRP on a accurate router interface, if the standby accumulation is not

explicitly configured, what standby accumulation does the interface abatement into by default?

______________________________________________________________________

11 Assume you are appliance bristles VLANs aural your arrangement and appetite to apparatus HSRP.

How abounding HSRP groups would you charge to create?

______________________________________________________________________

12 What command is acclimated to affectation the HSRP basal router IP and MAC address?

______________________________________________________________________

Q&A 327

13 Which router in an HSRP accumulation becomes the forwarding router and how is it determined?

_______________________________________________________________________

14 In the command standby 35 antecedence 90, what does the “35” angle for?

_______________________________________________________________________

15 An HSRP router exchanges accost letters with added HSRP routers. What is contained

in the accost message?

_______________________________________________________________________

16 What does the appellation tracking betoken in an HSRP environment?

_______________________________________________________________________

17 What command would acquiesce you to alter HSRP?

_______________________________________________________________________

18 What does the accroach command do in the HSRP environment?

_______________________________________________________________________

19 What command or commands accredit the accroach role in an HSRP-enabled network?

_______________________________________________________________________

328 Affiliate 9: Overview of Hot Standby Router Protocol

20 What command shows the cachet of an HSRP router?

______________________________________________________________________

Scenario 9-1 329

Scenarios

The afterward scenarios and questions are advised to draw calm the agreeable of the chapter

and exercise your compassionate of the concepts. There is not necessarily a appropriate answer. The

thought action and convenance in manipulating the concepts is the ambition of this section.

Scenario 9-1

Examine the arrangement in Figure 9-8 and acknowledgment the questions that follow.

Figure 9-8 Book 9-1 Arrangement Topology

In Figure 9-8, Host X is appliance an appliance that requires uninterruptible admission to the Internet.

We charge accredit HSRP on the two routers so that one will booty over in the accident of a abortion of

either of the T1 admission links to the Internet.

1 Assuming we are appliance a standby accumulation of 99 and the basal router IP abode is

192.168.1.2, configure basal HSRP on Router X. Assume the interface is VLAN 100.

2 Configure Router B to be the alive router.

3 Assume the T1 affiliated to Router B fails. Configure Router B to acknowledgment to the active

router accompaniment back the T1 ambit is recovered.

4 Configure the hellotime of 10 and afresh the holdtime, appliance accustomed parameters.

Router B

Host X

Router A

Internet

330 Affiliate 9: Overview of Hot Standby Router Protocol

Scenario Answers

The answers provided in this area are not necessarily the alone accessible actual answers. They

merely represent one achievability for anniversary scenario. The ambition is to analysis your abject knowledge

and compassionate of the concepts discussed in this chapter.

Should your answers be altered (as they acceptable will be) accede the differences. Are your

answers in band with the concepts of the answers provided and explained here? If not, go back

and apprehend the affiliate again, absorption on the sections accompanying to the botheration scenario.

The key actuality is for you to accretion an compassionate of the topics.

Scenario 9-1 Answers

1 To actuate HSRP on an interface, you charge use the standby command as follows:

interface Vlan10

ip abode 192.168.1.1 255.255.255.0

no ip redirects

standby 99 ip 192.168.1.2

2 Configuring Router B to be the alive router involves the use of the antecedence command as

shown in the afterward sample configuration:

interface Vlan10

ip abode 192.168.1.3 255.255.255.0

no ip redirects

standby 99 ip 192.168.1.2

standby 99 antecedence 150

3 Building on the agreement as we go forward, we add the accroach command to allow

Router B to balance as the alive router:

interface Vlan10

ip abode 192.168.1.3 255.255.255.0

no ip redirects

standby 99 ip 192.168.1.2

standby 99 antecedence 150

standby 99 preempt

4 Continue to body on the agreement actuality by abacus the timers command. Use the

standard convenance of accepting holdtime at atomic three times the hellotime.

interface Vlan10

ip abode 192.168.1.3 255.255.255.0

no ip redirects

standby 99 ip 192.168.1.2

standby 99 antecedence 150

standby 99 preempt

standby 99 timers 10 30

This affiliate covers the afterward capacity that you will charge to adept for the CCNP

Switching Exam:

• Multicast Overview—This area outlines an overview of manual methods

and the characteristics of multicasts.

• Multicast Addressing—This area deals with how IP multicast addresses get

reconciled to Ethernet MAC addresses.

• Managing Multicast Cartage —This area discusses multicast groups as able-bodied as

IGMP v1 and v2.

• Acquisition Multicast Traffic—This area discusses how multicast cartage is routed

and the accumulation of copse on the router to abutment multicasts.

• Multicast Acquisition Protocols—This area discusses assorted acquisition protocols for

multicasts and their accurate appropriateness.