PHP and MySQL Web Development 4th Ed-tqw-_darksiderg

Disaster Planning
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hosted burned down or was instantly destroyed in a massive earthquake. An alarming
percentage of them will have no answer at all.
Disaster (recovery) planning is a critical and frequently overlooked part of running a
service, whether it is a web application or anything else (including the day-to-day operations
of your business). It is usually a collection of documents or procedures that have
been rehearsed for dealing with the questions that arise when one of the following happens
(among many):
n Parts of or our entire data center is destroyed in some catastrophic event.
n Our development team goes out for lunch and all are hit by a bus and seriously
injured (or killed).
n Our corporate headquarters burns down.
n A network attacker or disgruntled employee manages to destroy all the data on the
servers for our web applications.
Although many people do not like to even talk about disasters and attacks for various
reasons, the hard reality is that such things actually do occur—fortunately, only rarely.
Businesses, however, usually cannot afford the downtime that an event of such magnitude
would cause if they were completely unprepared. A business that does millions of dollars
a day in business would be devastated if its web applications were shut down for over a
week while people not 100% familiar with the setup worked to get the systems up and
running again.
By preparing for these events, anticipating them with clear plans of action, and by
rehearsing some of the more critical portions of these, a little financial investment up
front can save the business from potentially disastrous losses later on when a real problem
does strike.
Some of the things we might do to help with disaster planning and recovery include
the following:
n Make sure that all data is backed up daily and taken off-site to another facility, so
that even if our data center is destroyed, we still have the data elsewhere.
n Have handwritten scripts, also off-site, on how to re-create the server environments
and set up the web application. Rehearse this re-creation at least once.
n
n
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Have a full copy of all source code necessary for our web application, also in multiple
locations.
For larger teams, prohibit all members of the team from traveling in one vehicle,
such as a car or airplane, so that if there is an accident, we will be affected less.
Have automated tools running to make sure that server operation is normal, and
have a designated “emergency operator” who will be responsible for coming in
during nonbusiness hours when a problem arises.
Make arrangements with a hardware provider to have new hardware immediately
available in the case that your data center is destroyed. It would be most frustrating
to have to wait 4 to 6 weeks for new servers.