Implement Blue-Green Deployment

Implement blue-green deployments using API7 Gateway to switch traffic between two upstream environments with zero downtime.

Blue-green deployment is a release strategy that maintains two identical production environments (Blue and Green). At any time, only one environment serves live traffic. When a new version is ready, traffic is switched to the other environment, enabling instant rollback if issues arise.

API7 Gateway implements blue-green deployments using the traffic-split plugin, which distributes traffic across multiple upstreams by weight.

Blue-green deployment switches 100% of traffic at once. For gradual traffic shifting (e.g., 10% to new version), see Canary Release.

Prerequisites

An API7 Enterprise instance is running.
A Gateway Group is created and a Gateway instance is running.
A token from the Dashboard.

Workflow Overview

Step 1: Prepare Upstreams

Create a service whose default upstream represents the Blue environment. The Green environment will be defined inline in the traffic-split plugin when you switch traffic.

Create the Blue service and route:

curl -k "https://localhost:7443/apisix/admin/services/blue-green-service?gateway_group_id={gateway_group_id}" -X PUT \
  -H "X-API-KEY: ${API_KEY}" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "blue-green-service",
    "upstream": {
      "type": "roundrobin",
      "scheme": "https",
      "pass_host": "node",
      "nodes": [
        {
          "host": "mock.api7.ai",
          "port": 443,
          "weight": 100
        }
      ]
    }
  }'

curl -k "https://localhost:7443/apisix/admin/routes/blue-green-route?gateway_group_id={gateway_group_id}" -X PUT \
  -H "X-API-KEY: ${API_KEY}" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "blue-green-route",
    "methods": ["GET"],
    "paths": ["/headers"],
    "service_id": "blue-green-service"
  }'

The default service upstream now represents the Blue environment.

Define the Blue service and route in your ADC configuration:

adc.yaml

services:
  - name: blue-green-service
    upstream:
      scheme: https
      pass_host: node
      nodes:
        - host: mock.api7.ai
          port: 443
          weight: 100
    routes:
      - name: blue-green-route
        uris:
          - /headers
        methods:
          - GET

adc sync -f adc.yaml

Step 2: Switch Traffic to Green

Apply the traffic-split plugin to route 100% of traffic to the Green upstream.

curl -k "https://localhost:7443/apisix/admin/routes/blue-green-route?gateway_group_id={gateway_group_id}" -X PUT \
  -H "X-API-KEY: ${API_KEY}" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "blue-green-route",
    "methods": ["GET"],
    "paths": ["/headers"],
    "service_id": "blue-green-service",
    "plugins": {
      "traffic-split": {
        "rules": [
          {
            "weighted_upstreams": [
              {
                "weight": 100,
                "upstream": {
                  "type": "roundrobin",
                  "nodes": [
                    {
                      "host": "httpbin.org",
                      "port": 443,
                      "weight": 1
                    }
                  ]
                }
              },
              {
                "weight": 0
              }
            ]
          }
        ]
      }
    }
  }'

Field	Description
Inline `upstream`	The Green upstream to receive traffic
`weight: 100` (Green)	All traffic goes to Green
`weight: 0` (no upstream_id)	No traffic to the default (Blue) upstream

adc.yaml

services:
  - name: blue-green-service
    upstream:
      scheme: https
      pass_host: node
      nodes:
        - host: mock.api7.ai
          port: 443
          weight: 100
    routes:
      - name: blue-green-route
        uris:
          - /headers
        methods:
          - GET
        plugins:
          traffic-split:
            rules:
              - weighted_upstreams:
                  - upstream:
                      type: roundrobin
                      scheme: https
                      pass_host: node
                      nodes:
                        - host: httpbin.org
                          port: 443
                          weight: 1
                    weight: 100
                  - weight: 0

adc sync -f adc.yaml

Step 3: Validate

Send test requests to confirm all traffic reaches the Green environment:

# Verify responses come from the Green (v2) backend
for i in $(seq 1 10); do
  curl -s "http://127.0.0.1:9080/headers" | grep 'X-Amzn-Trace-Id'
done

All responses should come from the Green upstream. In this example, httpbin.org responses include X-Amzn-Trace-Id, while the Blue upstream does not.

Rollback

To roll back to Blue, reverse the weights:

curl -k "https://localhost:7443/apisix/admin/routes/blue-green-route?gateway_group_id={gateway_group_id}" -X PUT \
  -H "X-API-KEY: ${API_KEY}" \
  -H "Content-Type: application/json" \
  -d '{
    "name": "blue-green-route",
    "methods": ["GET"],
    "paths": ["/headers"],
    "service_id": "blue-green-service",
    "plugins": {
      "traffic-split": {
        "rules": [
          {
            "weighted_upstreams": [
              {
                "weight": 0,
                "upstream": {
                  "type": "roundrobin",
                  "nodes": [
                    {
                      "host": "httpbin.org",
                      "port": 443,
                      "weight": 1
                    }
                  ]
                }
              },
              {
                "weight": 100
              }
            ]
          }
        ]
      }
    }
  }'

Update the traffic-split weights so the default upstream has weight 100 and the Green upstream has weight 0, or remove the plugin configuration entirely.

Cleanup

After the Green environment is verified and stable, you can:

Remove the traffic-split plugin from the route.
Update the service's default upstream to point to the Green nodes.
Decommission the old Blue environment.

Conditional Blue-Green Switch

You can also switch traffic conditionally — for example, based on a request header. This is useful for testing the Green environment with specific users before switching all traffic.

{
  "rules": [
    {
      "match": [
        {
          "vars": [["http_x_env", "==", "green"]]
        }
      ],
      "weighted_upstreams": [
        {
          "weight": 100,
          "upstream": {
            "type": "roundrobin",
            "scheme": "https",
            "pass_host": "node",
            "nodes": [
              {
                "host": "httpbin.org",
                "port": 443,
                "weight": 1
              }
            ]
          }
        }
      ]
    }
  ]
}

With this configuration:

Requests with header X-Env: green are routed to the Green upstream.
All other requests continue to the default (Blue) upstream.

Next Steps

Canary Release: Gradually shift traffic between versions.
Health Check: Monitor upstream health during deployments.
Fault Injection: Test resilience during deployment transitions.