Blue_Green_Deployment

This document outlines the blue/green deployment strategy where we maintain a single active cluster serving production traffic. The inactive cluster sits around awaiting a new deployment, before becoming active again.

While troubleshooting or working with blue-green deployments you might need to:

Identifying the Current Active Deployment

To determine which deployment is currently active:

1. Access the Grafana Dashboards.
2. Open the CI Runners Deployment Overview Dashboard.
3. Locate the ‘instance’ column in the ‘GitLab Runner Versions’ section to identify the active deployment.

Executing ChatOps Commands

Use ChatOps commands in the #production channel to manage deployments. It’s crucial to deploy only one environment (blue or green) at a time. The ChatOps commands logic lives in the Deployer repo

Deploying and Draining Runner Managers

1. Deploy the Green Environment (When Blue is Active): This command enables and executes chef-client on the green deployment to install the GitLab Runner version defined in the Chef repository. It also starts the GitLab Runner service.

   /runner run start private green

2. Drain the Blue Environment (After Green is Deployed): This command initiates the process of draining the runners and deleting the machines in the blue environment. This operation may take several hours up to a full day to complete.

   /runner run stop private blue

A list of all the the available commands can be found in Deployer repo

Support and Queries

For any questions or support, reach out to folks in #g_runner_saas Slack Channel.