How to avoid prolonged network downtime

The vast majority of IT networks are critical to firms these days because business is conducted in real time with tools like emails, online transactions, etc.

When I ask my clients how long a network outage they can tolerate, most usually say `nil’ without hesitation. When then informed that such a lofty ideal would cost lots of money to achieve most instantly soften and suggest that they could accept anything from four hours to two days.

I then ask them what strategy they have to ensure that they can recover in that time. Most rely on tape backups and some use removable hard drives. A few do offsite backups over the Net. Some use imaging technology. Surprisingly there are still firms that don’t do regular backups.

Most are surprised to hear that in a major disaster (such as server failure) with most traditional strategies the chances of a recovery in fewer than two days are not very high. There are numerous challenges to quick recovery: the availability of replacement servers or parts; the capability for restoring the operating system quickly; and the ability to restore the data rapidly.

How hastily you can procure a replacement server is dependent on whether your IT provider has spare servers sitting around. Buying a new one usually requires more time. Likewise with the procurement of replacement parts. While the server is under warranty the manufacturers will ENDEAVOUR to cough up with the parts as quickly as possible but note that this is not guaranteed. As the server gets older it becomes much much harder to get parts quickly.

In a major failure you may not be able to recover the operating system from backup and it has to be `rebuilt’ from scratch. Some firms use imaging technology such as Shadow Protect to eliminate the need to rebuild but even with such help the restoration of the system can take anywhere from four to eight hours or more because of the need to first restore the image.

The trick to avoid this additional downtime is to use backups that you can run without first having to restore. Recently such technologies have appeared that allow you to achieve sub-one-hour recovery at very little cost.

Most businesses cannot and should not tolerate prolonged network downtimes. Check with your IT services provider that your disaster recovery regime allows you to get your system back on its feet within your required timeframe.

By Alan Chew

Managing Director of the Houston Technology Group

This article appeared in the June 2009 edition of the Waikato Business News, for which Alan writes a regular column as "Your IT Adviser".