Multiple frontend rules in Traefik Consul integration

Question

I'm using Traefik to load balance across different services registered in Consul.

I'm using the consul-catalog configuration and overriding a front end routing rule for one of the services by adding a tag when defining the service in consul:

tags=[“traefik.frontend.rule=PathPrefixStrip:/api,Host:api.service.consul”]

I'm expecting both /api and api.service.consul to resolve to my service, however only /api is successful, however api.service.consul returns a 404 error.

In other words, only the first rule is being considered. If I switch the tag around:

tags=[“traefik.frontend.rule=Host:api.service.consul,PathPrefixStrip:/api”]

Then api.servie.consul resolves and /api returns a 404 error.

I believe the docs suggest this configuration is supported. Has anyone else had success with defining multiple rules via consul tags?

Answer 1

Edit: Since v1.7, for consul-catalog, you can use: multiple-frontends-for-a-single-service

tags=[
"traefik.frontends.foo.rule=Host:api.service.consul",
"traefik.frontends.bar.rule=PathPrefixStrip:/api",
]

---

The answer can be seen at https://github.com/containous/traefik/issues/2417:

• , is the OR operator (works only inside a matcher, ex: Host:foo.com,bar.com)
• ; is the AND operator (works only between matchers, ex: Host:foo.com;Path:/bar)

So, for your example, use:

tags=["traefik.frontend.rule=Host:api.service.consul;PathPrefixStrip:/api"]

Documentation links:

• https://docs.traefik.io/v1.5/basics/#matchers
• https://docs.traefik.io/v1.5/basics/#combining-multiple-rules
• https://docs.traefik.io/v1.5/configuration/backends/consulcatalog/