Chapter 2.5


is the implementation of alternate means to perform work tasks or accomplish IT functions to support or maintain availability of a resource or service

Geographic dispersal



r storage resources should be implemented with redundancy

Load balancers

e used to spread or distribute network traffic load across several network links or network devices

Network interface card (NIC)

is the bonding, binding, or grouping of two or more NICs together to act as a single connection to the network

Uninterruptible power supply (UPS)

is a power conditioner and battery backup that ensures that only clean, pure, nonfluctuating power is fed to computer equipment


can be used to provide replacement or supplemental power by consuming fuel until the power grid is restored

Dual supply

reference to having two power supplies for essential equipment

Managed power distribution units (PDUs)

are often used in combination with rack-mounted equipment to remotely monitor and control the power consumption of the individual computing systems

Storage area network

can be a single point of failure, so redundancy needs to be integrated to provide protection of availability

Full backup

copies all files to the backup media regardless of the archive bit setting

Incremental backup

p copies only those files with a set or flagged archive bit

Snapshot backup

are typically related to virtual machines (VMs) where the hypervisor is able to make a live copy of the active guest OS and its contents

Differential backup

copies only those files with a set or flagged archive bit

Tape backup

Modern tapes are fast and have an astounding capacity


file function of making a clone of a file into a new location

Network-attached storage (NAS)

is a network device dedicated as a file server that is used by other systems across the network to store files