Rollback
Reverting a running system to a previous known-good version, as distinct from fixing forward.
Rollback reverts a deployed system to a previous version after a release turns out to be bad. It is the release-time counterpart to git revert in source control: instead of undoing the change in history, you redeploy an artifact that already worked. The whole point is speed — a rollback exists to stop the bleeding now, not to diagnose or fix the underlying bug, which can happen afterward at normal pace.
How fast a rollback is depends entirely on what has to move to make it happen. Repointing a load balancer between two live Blue-Green Deployment environments is close to instant. Redeploying a previous container image is a build-free but not zero-time operation. Worst is anything that touched shared state: a Database Migration that dropped a column can't be rolled back by redeploying old code if that code now queries a column that no longer exists. This is why migrations are written to be backward-compatible for at least one release — rollback safety is designed in ahead of the release, not improvised during the incident.
The alternative discipline is "fix forward": rather than reverting, ship a fix as fast as possible on top of the bad release. Fixing forward is sometimes forced — when the bad release already committed side effects (sent emails, charged cards) that reverting the code can't undo — and sometimes chosen, when the team judges a targeted fix is faster or safer than an untested revert. Neither approach is universally correct; picking between them under incident pressure is exactly the kind of decision a rehearsed rollback plan exists to make routine instead of improvised.
See also5
Zero-Downtime Deployment
Deploying a new version while the service keeps serving every request, with no maintenance window.
Version Control & Delivery9 connections
Canary Release
Shipping a change to a small slice of traffic first, and only widening it once that slice looks healthy.
Version Control & Delivery12 connections
Immutable Infrastructure
Replacing servers wholesale on every change instead of patching them in place.
Version Control & Delivery8 connections
Hotfix
An urgent fix shipped outside the normal release flow, how teams branch and backport it, and why the healthiest hotfix process is the normal process run fast.
Version Control & Delivery6 connections
Progressive Delivery
Releasing a change to a growing share of users while watching its effect, so problems are caught when they affect few people and the rollout halts automatically.
Version Control & Delivery7 connections
Linked from13
- Artifact RepositoryVersion Control & Delivery
The store for the built outputs of software, such as packages, container images, and binaries, so the exact thing that was tested is the exact thing that ships.
- Blue-Green DeploymentVersion Control & Delivery
Running two identical production environments and switching traffic between them instead of upgrading one in place.
- Canary ReleaseVersion Control & Delivery
Shipping a change to a small slice of traffic first, and only widening it once that slice looks healthy.
- Cherry-PickVersion Control & Delivery
Copying the change from one commit onto another branch as a new commit, the standard way to backport a fix without merging everything else that came with it.
- GitOpsVersion Control & Delivery
Using a Git repository as the live source of truth for deployed state, reconciled continuously by an in-cluster agent.
- HotfixVersion Control & Delivery
An urgent fix shipped outside the normal release flow, how teams branch and backport it, and why the healthiest hotfix process is the normal process run fast.
- Immutable InfrastructureVersion Control & Delivery
Replacing servers wholesale on every change instead of patching them in place.
- Optimistic UIWeb Platform
Updating the UI as if a server request has already succeeded, before the server has actually responded.
- Progressive DeliveryVersion Control & Delivery
Releasing a change to a growing share of users while watching its effect, so problems are caught when they affect few people and the rollout halts automatically.
- Smoke TestTesting & Verification
A fast, shallow check that a build isn't catastrophically broken, run before investing in a deeper test pass.
- UndoDesign & Interface
Letting people reverse what they just did, which makes interfaces safe to explore and usually beats asking "are you sure?" before every action.
- Watchdog TimerSystems & Tooling
A countdown that resets a system unless healthy software keeps restarting it, the last line of defense against hangs in spacecraft, routers, and servers.
- Zero-Downtime DeploymentVersion Control & Delivery
Deploying a new version while the service keeps serving every request, with no maintenance window.