We have all experienced an accident or made a mistake before. We're only human, right? As an IT support specialist, It's important that you're prepared for a disastrous accident or mistake. Maybe an electrical surge fried the hard drive in a database server or someone deleted the wrong folder. These things happen and you need to be prepared for them. This is where the disaster recovery plan comes in. A disaster recovery plan is a collection of documented procedures and plans on how to react and handle an emergency or disaster scenario, from the operational perspective. This includes things that should be done before, during and after a disaster. The goal of the disaster recovery plan is to minimize disruption to business and IT operations, by keeping downtime of systems to a minimum and preventing significant data loss. Despite the name, a disaster recovery plan will actually cover preventive measures and detection measures on top of the post disaster recovery approach. Preventative measures cover any procedures or systems in place that will proactively minimize the impact of a disaster. This includes things like regular backups and redundant systems. Anything that's done before an actual disaster that's able to reduce the overall downtime of the event is considered preventative. For example, a standard for critical network infrastructure or service to have redundant power supplies. They're often fed from different power sources like battery backup. This is designed to minimize the downtime that would be caused by one power supply failing or a power outage. That would be a preventative measure. We're going to some more detail on this in the next lesson, when we cover designing and effective disaster recovery plan. Detection measures are meant to alert you and your team that a disaster has occurred that can impact operations. Obviously, you need to be aware of a disaster in order to take appropriate steps to reduce the impact on your organization. Timely notification of a disaster is critical, since some steps of the disaster recovery plan might be time sensitive to ensure there is no data loss or equipment damage. If there a power outage for example, critical systems should fall back to battery power. But, battery backup power will only keep the systems on line for so long. To avoid potential data loss or damage, these systems should be gracefully shut down before they completely lose power. This is why lots of systems that support redundant power supplies also have a function to send alerts on power loss events. Other things that should be monitored to help head off any unexpected disasters include environmental conditions inside several networking rooms. Flood sensors can alert you to water coming into the server. Temperature and humidity sensors can watch for dangerously high temperatures or some optimal moisture levels in the air. This can alert you to failed cooling in the server room. Smoke detectors and fire alarms are also critically important. Remember, that it isn't just the technology that's necessary for a business to continue to operate. You also need the people working there. The specifics of building evacuation usually forward to the building management team, but as an IT support specialist, you'll likely work closely with some members of this team on things like, power delivery, heating and cooling systems and building evacuation. If there's a fire and the building needs to be evacuated, you should be prepared to set up temporary accommodation so people can still work effectively. This might be as simple as sending everyone home for the day and having them work from home. But you should be prepared for the situation ahead of time and have a plan in place to ensure that everyone is able to work from home effectively. Finally, corrective or recovery measures are those enacted after disaster has occurred. These measures involve steps like restoring lost data from backups or rebuilding and reconfiguring systems that were damaged. Once the disaster has been detected and steps have been taken to either prevent an outage or at least minimize downtime, work should begin on restoring full operations of everything affected. Usually, a disaster will take out one system that's part of a redundant pair or a replication scheme which would prevent a complete service outage. But that would mean you aren't prepared for another disaster. When one system in a redundant pair suffers a failure, it's called a single point of failure. This is because it only takes one failure now to completely take the system down. That's not a scenario you want to be in. We've covered the overall elements of a disaster recovery plan. Why don't you take a little break to recover yourself, then join me in the next video. We're going to run down the details of designing a disaster recovery plan of your own. Does that include planning for the zombie apocalypse? You have to watch to find out.