Applicability
When to Use
✓When zero-downtime deployments are required
✓When you need instant rollback capability
✓When deployment validation must be automated
Overview
How It Works
Blue-Green deployment maintains two identical environments. The 'blue' environment runs the current version while 'green' runs the new version. MCP servers are used to validate the green environment (run health checks, test key workflows), and once validated, traffic is switched from blue to green.
The MCP agent orchestrates the entire process: deploy to green, run validation, switch DNS/load balancer, monitor for issues, and rollback if problems are detected within the canary window.
Implementation
Code Example
typescript
async function blueGreenDeploy(newVersion) {
// Deploy to green environment
await kubernetes.patchDeployment({ name: "app-green", image: `app:${newVersion}` });
await kubernetes.waitForRollout({ deployment: "app-green" });
// Validate green
const health = await puppeteer.checkPage(`https://green.internal/health`);
const smoke = await runSmokeTests("https://green.internal");
if (!health.ok || !smoke.allPassed) {
await slack.sendMessage({ channel: "#deploys", text: `Validation failed for ${newVersion}` });
return;
}
// Switch traffic
await aws.updateDNS({ recordName: "app.example.com", value: "green.internal" });
await slack.sendMessage({ channel: "#deploys", text: `Switched to ${newVersion}` });
// Monitor for 10 minutes
await monitorErrorRate(10, async () => {
await aws.updateDNS({ recordName: "app.example.com", value: "blue.internal" });
await slack.sendMessage({ channel: "#deploys", text: `Rolled back from ${newVersion}` });
});
}Quick Info
Categorydeployment
ComplexityHard