Traefik Ingress Operator for Kubernetes
- Canonical Observability
Channel | Revision | Published | Runs on |
---|---|---|---|
latest/stable | 194 | 01 Aug 2024 | |
latest/candidate | 199 | 28 Jun 2024 | |
latest/beta | 203 | 01 Aug 2024 | |
latest/edge | 213 | 18 Oct 2024 | |
1.0/stable | 164 | 16 Feb 2024 | |
1.0/candidate | 164 | 22 Nov 2023 | |
1.0/beta | 164 | 22 Nov 2023 | |
1.0/edge | 164 | 22 Nov 2023 |
juju deploy traefik-k8s --channel beta
Deploy Kubernetes operators easily with Juju, the Universal Operator Lifecycle Manager. Need a Kubernetes cluster? Install MicroK8s to create a full CNCF-certified Kubernetes system in under 60 seconds.
Platform:
After relating traefik to your charm, you may encounter reachability errors such as:
- Internal server error
- 404 page not found
Checklist
- Your charm either uses open-port1,2 or applies a kubernetes service patch for exposing the workload’s port.
- Your workload is not bound to a particular IP address, i.e. it is listening on “0.0.0.0”.
- You either pass
strip_prefix=True
to the ingress library, or your workload’s pebble command includes the path prefix generated by traefik (/model_name-app_name
) so your app is serving correctly. - The SANs in your workload’s certificate match the url in traefik’s config.
- Traefik trusts the same CA that signed your workload’s certificate.
- Inspect logs.
Workload is correctly exposed
juju ssh
into the charm container and run ss -tulpn
. Find your app’s port in the list and make sure it is not bound to a particular IP, e.g.
Local Address:Port
*:3200
*:9096
Also make sure kubernetes has your ports listed as ClusterIP, for example:
$ kubectl -n welcome-k8s get svc
NAME TYPE CLUSTER-IP EXTERNAL-IP PORT(S) AGE
tempo ClusterIP 10.152.183.237 <none> 3200/TCP,4317/TCP,4318/TCP,9411/TCP,14268/TCP,14250/TCP 30m
Ingress path prefix is handled correctly
By default, traefik uses deterministic paths to all proxied endpoints, such as http://<traefik ip>/model_name-app_name
.
This means that you need to tell your workload about it (for example alertmanager takes a --web.external-url
cli arg) or tell traefik to strip prefix:
self.ingress = IngressPerAppRequirer(
self,
"ingress",
port=self._port,
scheme=lambda: "https" if self.server_cert.cert else "http",
redirect_https=True,
strip_prefix=True,
)
Workload’s certificate has the correct SAN DNS
To avoid using insecureSkipVerify
in traefik configuration, the url specified in the traefik config must match the DNS in the cert.
Shell into the traefik workload container to confirm:
$ juju ssh --container traefik trfk/0 bash
root@trfk-0:/# cat /opt/traefik/juju/juju_ingress_ingress_48_am.yaml | grep url
- url: https://am-0.am-endpoints.welcome-k8s.svc.cluster.local:9093
root@trfk-0:/# echo | openssl s_client -showcerts -connect am-0.am-endpoints.welcome-k8s.svc.cluster.local:9093 | openssl x509 -text | grep DNS
DNS:am-0.am-endpoints.welcome-k8s.svc.cluster.local
Traefik trusts the same CA that signed your workload’s certificate
To avoid using insecureSkipVerify
in traefik configuration, traefik must trust the CA that signed the proxied app’s certificate.
Shell into the traefik workload container to confirm:
$ juju ssh --container traefik trfk/0 bash
root@trfk-0:/# cat /opt/traefik/juju/juju_ingress_ingress_48_am.yaml | grep -E "url|cert"
- /opt/traefik/juju/ca.cert
- url: https://am-0.am-endpoints.welcome-k8s.svc.cluster.local:9093
root@trfk-0:/# curl --capath /opt/traefik/juju \
--cacert /opt/traefik/juju/ca.cert \
https://am-0.am-endpoints.welcome-k8s.svc.cluster.local:9093/welcome-k8s-am/-/ready
OK
Inspect traefik’s log
Make sure traefik is running.
$ juju ssh --container traefik trfk/0 /charm/bin/pebble changes traefik
ID Status Spawn Ready Summary
1 Done today at 13:20 UTC today at 13:20 UTC Replan service "traefik"
$ juju ssh --container traefik trfk/0 /charm/bin/pebble tasks 1
Status Spawn Ready Summary
Done today at 13:20 UTC today at 13:20 UTC Start service "traefik"
Look at the traefik log as you add/remove relations:
kubectl -n welcome-k8s logs pods/trfk-0 -c traefik -f