Technical Disaster Recovery Plan

What a disaster recovery plan is

A technical disaster recovery (DR) plan is the document that tells your team exactly how to bring critical systems back online after an event that takes them down — a region outage, a database corruption, a ransomware incident, a botched deployment, or a hardware failure. It answers two questions under pressure: what do we do, and in what order?

A good DR plan is not a vague intention to "have backups." It is a tested, step-by-step set of procedures with named owners, target recovery times, and a recovery checklist that someone who is tired and stressed at 3am can follow without improvising.

Key concepts: RTO, RPO, backup vs DR, failover

Four terms do most of the work in a DR plan, so define them clearly up front.

• RTO (Recovery Time Objective) — the maximum acceptable time a system can be down before the outage causes serious harm. "Checkout must be back within 30 minutes" is an RTO. It drives how much you invest in fast recovery (hot standby vs. rebuild-from-backup).
• RPO (Recovery Point Objective) — the maximum acceptable amount of data loss, measured in time. An RPO of 5 minutes means you can afford to lose at most the last 5 minutes of data; it dictates how often you back up or replicate. RTO is about downtime; RPO is about data.
• Backup vs DR — a backup is a copy of data you can restore from. Disaster recovery is the whole capability: backups plus the runbooks, infrastructure, roles, and tested procedures to actually get a working system back. Backups are necessary but not sufficient — an untested backup is a hope, not a plan.
• Failover — switching production traffic from a failed system to a standby (a replica database, a second region, a warm instance). Failover can be automatic (health checks flip traffic) or manual (an engineer promotes a replica). Either way, the steps and the trigger conditions belong in the plan.

The components of a disaster recovery plan

Required

• Scope and critical systems — which systems the plan covers and how critical each one is. Not everything needs the same RTO; a marketing blog and a payments database are not equals.
• RTO and RPO targets per system — the numbers your recovery decisions are measured against.
• Backup strategy — what is backed up, how often, where it is stored, how long it is retained, and how restores are verified. Off-site or cross-region copies matter; a backup in the same region as the failure is not a backup.
• Failover and recovery procedures — ordered, concrete steps for each failure scenario, including who triggers them and how you confirm success.
• Roles and contacts — who declares a disaster, who executes recovery, who communicates with customers, and how to reach them out of hours.
• Communication plan — what you tell customers and stakeholders, through which channels, and when.
• Test schedule — when and how the plan is exercised (see below).

Optional but valuable

• Dependency map — which systems depend on which, so you recover in the right order.
• Post-incident review process — how you capture lessons and update the plan afterwards.

Testing the plan

An untested DR plan should be assumed broken. Backups silently fail, credentials expire, runbooks go stale, and the one engineer who knew the failover steps leaves. Test on a schedule and treat every test as evidence.

• Tabletop exercises — walk through a scenario as a group without touching production. Cheap, fast, and good for finding gaps in ownership and communication.
• Restore drills — actually restore a backup to a scratch environment and confirm the data is complete and usable. This is the single highest-value test, because it catches the most common silent failure: backups that cannot be restored.
• Failover drills — promote a replica or fail over to the standby region and measure real RTO. Do this in a controlled window before you are forced to do it for real.
• Record results — every test should produce a measured recovery time, a list of what broke, and fixes folded back into the plan. Update the "last tested" date.

How it differs from a maintenance or security plan

These documents overlap but answer different questions, and conflating them leaves gaps.

• A maintenance plan keeps a healthy system healthy — patching, monitoring, backups running, capacity. It is routine and proactive. The DR plan takes over when maintenance has failed to prevent an outage and you need to recover.
• A security plan is about preventing and detecting unauthorised access and protecting data. The two meet at incidents like ransomware, where security responds to the breach and DR restores clean service from backups — but they are not the same document.
• A deployment plan covers shipping changes safely, including rollback. Rollback handles a bad release; DR handles a destroyed or unavailable system. Keep them distinct so neither gets buried in the other.

Common mistakes to avoid

• Confusing backups with DR. Having backups is not a recovery capability until you have tested restoring from them and timed it.
• Setting RTO and RPO by wishful thinking. Targets you cannot actually meet are worse than honest ones, because they create false confidence. Test, then set targets you can hit.
• Storing backups beside the thing that fails. A backup in the same region, account, or disk as production dies with it. Keep an isolated, off-site or cross-region copy.
• No named owners. "The team" recovers nothing at 3am. Name a person (and a backup) for each role.
• Never testing. The most common reason DR fails in a real event is that the plan had never been exercised end to end.
• Letting it go stale. Systems change weekly; a DR plan reviewed once a year describes a system that no longer exists. Tie reviews to a schedule and to major architecture changes.