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Mistake in Case Study: Dial Backup with Two Routers?

Hi, i was studying "Case Study: Dial Backup with Two Routers" from book

Advanced IP Network Design (CCIE

Professional Development)

Alvaro Retana

Don Slice

Russ White

it confused me little, attached is 2 pages of the case study, please check that and let me know if there is any mistake?

Book Say, in case study:  If Router B fails, Router D will take over as the active HSRP router and will begin

forwarding traffic across the ISDN link.

My Qustion is why Router B will be primary HSRP gateway? its priority is less. so Router D should be gateway in first case.

2nd Question.

Book Says: When Router B's serial interface fails, it will increase its standby priority to 30, and

Router D will take over as the HSRP active router.

What does this mean? If Priority of B will increase then it should be Active , not Router D.

Please explain, if this book is correct? or may be i am on mistake?


Mistake in Case Study: Dial Backup with Two Routers?


you're correct , router D should be the active router as its priority is higher than router B.

Concerning the track command, if the tracked interface fails then the priority should be decreased to get lower than the standby router priority which will take over as active provided it has preemption enabled.



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