Rollback deployments in Firebase - Step-by-Step Execution

Process Flow - Rollback deployments

Start Deployment

↓

Deploy New Version

↓

Check Deployment Status

↓

Keep

↓

Deploy Previous Version

↓

Deployment Stable

↓

End

This flow shows deploying a new version, checking if it works, and rolling back to the previous version if it fails.

Execution Sample

Firebase

firebase deploy --only hosting
# Check deployment
# If failure, run:
firebase hosting:channel:rollback

Deploys a new hosting version, then rolls back if deployment fails.

Process Table

Step	Action	Deployment Version	Status Check	Result
1	Deploy new version v2	v2	Pending	Deployment started
2	Check deployment status	v2	Failed	Trigger rollback
3	Rollback to previous version v1	v1	Success	Deployment stable
4	End process	v1	N/A	Rollback complete, stable version running

💡 Rollback completed because new deployment v2 failed status check

Status Tracker

Variable	Start	After Step 1	After Step 2	After Step 3	Final
Deployment Version	v1	v2	v2	v1	v1
Deployment Status	Stable	Pending	Failed	Stable	Stable

Key Moments - 3 Insights

Why do we deploy version v2 before checking if it works?

Because deployment must happen first to test if the new version is stable, as shown in step 1 and 2 of the execution_table.

What happens if the deployment status is successful?

If successful, rollback is not triggered and the new version stays live, but in this example, failure caused rollback at step 2.

Does rollback deploy the exact previous version?

Yes, rollback redeploys the last stable version, here v1, as shown in step 3.

Visual Quiz - 3 Questions

Look at the execution table, what is the deployment version after step 3?

A v2

B v3

C v1

D None

💡 Hint

Check the 'Deployment Version' column at step 3 in the execution_table.

At which step does the deployment status become 'Failed'?

A Step 1

B Step 2

C Step 3

D Step 4

💡 Hint

Look at the 'Deployment Status' column in the variable_tracker after step 2.

If the deployment status was 'Success' at step 2, what would happen next?

A Keep new version live

B Rollback to previous version

C Deploy a new version v3

D End with failure

💡 Hint

Refer to the concept_flow where success leads to keeping the new version.

Concept Snapshot

Rollback deployments:
- Deploy new version
- Check if deployment works
- If fails, rollback to previous stable version
- Use 'firebase hosting:channel:rollback' to revert
- Ensures stable live environment

Full Transcript

This visual execution shows how deploying a new Firebase hosting version works. First, a new version is deployed. Then the deployment status is checked. If the deployment fails, a rollback is triggered to redeploy the previous stable version. This process ensures the live site stays stable. The execution table traces each step, showing deployment versions and status changes. Key moments clarify why deployment happens before checking and how rollback restores stability. The quiz tests understanding of deployment versions and status at each step.