Networking: A Beginner's Guide
If you do not yet have an off-site storage procedure, you should seriously consider
adopting one. While fireproof file cabinets can protect tape media from small fires, they are not
necessarily invulnerable to very large or hot fires. Plus, tapes are more sensitive to smoke and heat
than the papers that a fireproof file cabinet is designed to protect.
Companies that provide off-site storage of files often also offer standardized tape-
storage practices. These usually work on a rotation basis, where a storage company
employee comes to your office periodically--usually weekly--and drops off one set
of tapes and picks up the next set of tapes. The companies typically use stainless steel
boxes to hold the tapes, and the network administrator is responsible for keeping the
boxes locked and safeguarding the keys. You need to decide which tapes you should
keep on-site and which ones to send off-site. One rule of thumb is always to keep the
two most recent complete backups on-site (so that they're available to restore deleted
files for users) and send the older tapes off-site. This way, you keep on hand the tapes
that you need on a regular basis, and you minimize your exposure to a disaster. After
all, if a disaster destroys your server room and all of the tapes in it, you probably won't
be too worried about losing just a week's worth of data.
The amount of data that you can accept exposing to a disaster will vary widely depending on
the nature of your company's business and the nature of the data. Some operations are so sensitive
that the loss of even a few minutes' worth of data would be catastrophic. For example, a banking
firm simply cannot lose any transactions. Businesses that need to protect supersensitive data
sometimes enlist a third-party vendor to provide off-site online data storage. Such a vendor replicates
a business's data onto the vendor's servers over a high-speed connection, such as a T-1 or T-3.
These vendors usually also offer failover services, where their computers can pick up the jobs of your
computers should your computers fail. Alternatively, if a business runs multiple sites, it might set up
software and procedures that enable it to accomplish the same services using its own sites.
Describing Critical Components
Your plan should describe the computer equipment and software that will be required
to resume operations if the entire building is lost. This list should roughly estimate the
cost of the equipment and how it can be procured rapidly. By preparing such a list,
you can reduce the time required to resume operations in a temporary facility. Also, if
your company purchases insurance against business interruptions, you will need these
estimates for that insurance policy.
Network Backup and Restore Procedures
A network disaster recovery plan is worthless without some way of recovering the data
stored on the server. This is where network backup and restore procedures come in.
If you're a network administrator, or aspire to become one, you should already know
about the importance of good backups of the system and of important data. If you don't