Unix® System Management Primer Plus

Location Redundancy

To high availability for your system, you most provide for full redundancy—and that includes having a second data center, in case your primary data center becomes unavailable. Installing redundant hardware at these backup data centers guards against location-specific failures such as natural disasters, broken telco lines, excessive network traffic, and routing problems; you learned this in Chapter 9, “Preparing for Disaster Recovery.” When such failures occur, you can direct all traffic to your backup site through various means, including static routing and readdressing in DNS.

But hardware is only part of location redundancy; you must have a copy of your data at the other site. The traditional way to accomplish this is by ...