kong – 2 services same route

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In Kong Gateway, you cannot have two services bound to the exact same route — a route must be unique in terms of its combination of matching rules (such as paths, hosts, methods, etc.).

Why You Can’t Have Duplicate Routes

Kong uses the route’s matching criteria to determine which service should handle a request. If two routes have the same matching rules, Kong can’t disambiguate, which leads to a conflict error when trying to create the second route.

For example:

# Service A
curl -i -X POST http://localhost:8001/services/ --data name=service-a --data url=http://api-a
curl -i -X POST http://localhost:8001/routes --data name=route-a --data service.name=service-a --data paths[]=/api

# Service B
curl -i -X POST http://localhost:8001/services/ --data name=service-b --data url=http://api-b
curl -i -X POST http://localhost:8001/routes --data name=route-b --data service.name=service-b --data paths[]=/api

The second POST /routes will fail with:

HTTP 409 Conflict – duplicate entry

Workarounds / Alternatives

GoalSolution
Blue/Green or Canary DeploymentsUse Kong Plugins (e.g., traffic-split, canary) or upstreams and targets instead of duplicate routes.
Different consumers/users hitting different backendsUse request transformers, ACLs, or Kong Enterprise Route-by-header/Route-by-consumer plugins.
Same path, different method or hostYou can differentiate routes by methods[], hosts[], or headers.

🧪 Example: Two Routes with Same Path, Different Hosts

# Route 1
curl -i -X POST http://localhost:8001/routes \
  --data name=api-v1 \
  --data paths[]=/api \
  --data hosts[]=v1.example.com \
  --data service.name=service-a

# Route 2
curl -i -X POST http://localhost:8001/routes \
  --data name=api-v2 \
  --data paths[]=/api \
  --data hosts[]=v2.example.com \
  --data service.name=service-b

These can coexist because their hosts[] fields are different.

Summary

Route Matching RuleMust Be Unique For
paths[]Same host/methods/headers
hosts[]If combined with same path
methods[], headersCan disambiguate routes with same path

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