Docker: Traefik route rules that silently fail — fix labels the right way

You deployed. Containers are healthy. Ports are open. DNS points correctly. And yet Traefik returns a calm, indifferent 404 like it’s doing you a favor.

This failure mode is why people call reverse proxies “simple”: because they simplify your system by concentrating all your mistakes in one place. Traefik + Docker labels is powerful, but it’s also a foot-gun with a polite muzzle. It won’t always scream when your route rules don’t match. It will just… route nothing.

What “silently fail” really means in Traefik

“Silently fail” doesn’t mean Traefik is broken. It means Traefik is doing exactly what you told it to do—based on labels you accidentally told it.

Typical symptoms:

• Traefik returns 404 page not found for a host you’re sure exists.
• You hit Traefik’s entrypoint, but the router never matches, so it falls back to the default handler (404).
• The container is up and listening, but Traefik routes to the wrong internal port (or none).
• Middlewares don’t apply, TLS doesn’t engage, redirects don’t happen, and you feel haunted.

Traefik isn’t “silent” if you know where to look: the dashboard, provider config, dynamic config view, and logs. The silence is on your terminal because Docker labels are easy to type wrong and hard to visually validate.

Interesting facts and a little context

1. Traefik popularized “configuration discovery” in the container era: watch Docker events, build routes dynamically, avoid hand-edited proxy configs.
2. Docker labels predate Traefik’s dominance; they were a generic metadata feature that reverse proxies repurposed into a full control plane.
3. Traefik v2 was a breaking mental-model change: routers, services, middlewares replaced the simpler v1 frontend/backend model. Many “it worked last year” configs died here.
4. Rule parsing got stricter over time: small syntax errors in Host(), quoting, or backticks often stop a router from existing at all.
5. EntryPoints are not ports; they’re named listeners. A router bound to websecure won’t match traffic arriving on web, even if both are on the same container.
6. Docker Compose YAML types bite hard: a label that looks like a string might be parsed weirdly unless you quote it.
7. Traefik defaults can hide your intent: if exposedByDefault is true, you might accidentally route to containers you never labeled—until you flip it and everything disappears.
8. HTTP/3 experiments changed expectations: newer edge stacks push QUIC; misaligned entrypoints and TLS settings are now more visible because clients retry differently.

Fast diagnosis playbook (do this in order)

If you’re on-call and bleeding minutes, stop guessing. Check the system the way Traefik experiences it.

1) Is Traefik receiving the request on the entrypoint you think?

• Confirm the client is hitting the right IP/DNS.
• Confirm the request reaches Traefik (not a cloud LB health page or old IP).
• Confirm HTTP vs HTTPS and SNI host.

2) Does Traefik have a router that could match?

• Check the dashboard or API for routers.
• Look for your router name; verify rule, entrypoints, TLS, and service binding.

3) If the router exists, does it match?

• Compare request host/path to the rule exactly.
• Look for priority conflicts and “catch-all” routers.

4) If it matches, can Traefik reach the service?

• Validate Docker network connectivity: Traefik must share a network with the target container.
• Verify the port Traefik uses is correct: explicit load balancer port beats auto-detection.

5) If it reaches the service, are middlewares and TLS doing what you think?

• Confirm middleware chain names and provider scope (@docker vs @file).
• Verify TLS settings: tls=true, certresolver, domains, and entrypoint.

That’s the order. Don’t invert it. Most time is wasted debugging “certs” when the router never matched in the first place.

How Traefik decides where traffic goes (and why labels matter)

In Traefik v2, the request flow is:

1. EntryPoint accepts the connection (example: web on :80, websecure on :443).
2. Router matches the request (rule: host/path/headers, plus entrypoints, plus TLS requirement).
3. Middlewares mutate the request/response (redirect, auth, headers, rate-limit, etc.).
4. Service defines the upstream (container IP:port, load balancing options).

Docker labels are the dynamic config source. The Docker provider watches containers and translates labels into routers/services/middlewares.

Here’s the crucial bit: Traefik will happily run with a partial config. If your router label is malformed, Traefik may not create that router at all. If your router exists but points at a nonexistent middleware, it may fail to attach it. If your service port label is missing and Docker exposes multiple ports, Traefik might pick the wrong one.

And if no router matches, Traefik returns a 404 that looks exactly like “Traefik is up.” That’s why people lose hours.

One quote worth remembering, because it’s the whole job:

“Hope is not a strategy.” — Gene Kranz

Traefik label debugging is where hope goes to die. Good. Replace it with observability and conventions.

Fix labels the right way: patterns that don’t rot

Principle 1: Always name routers, services, and middlewares explicitly

Relying on implicit naming is how you end up with “why is Traefik attaching the wrong service?” at 2 a.m. Use stable names. Use them everywhere.

Principle 2: Always specify the service port

Yes, Traefik can auto-detect ports. No, you should not let it, unless you enjoy probabilistic routing.

Rule of thumb: if a container exposes multiple ports, or if you’re using health/admin ports, always set:

• traefik.http.services.<service>.loadbalancer.server.port

Principle 3: Use one router per hostname + entrypoint, then compose behavior with middlewares

Don’t jam too much into a single router rule. Keep matching simple; keep behavior modular.

Principle 4: Quote label values in Compose (and be consistent with backticks)

Compose is YAML. YAML has opinions. Traefik rule syntax has opinions too. You’re stuck between two parsers with different definitions of “string.” Quote your labels. Use backticks inside Traefik rules consistently.

Good (quoted): "Host(`app.example.com`) && PathPrefix(`/api`)"
Bad (unquoted): Host(`app.example.com`) (works sometimes, until it doesn’t)

Principle 5: Decide whether you want to expose containers by default. Then enforce it.

In production, set Docker provider exposedByDefault=false and explicitly enable per service with traefik.enable=true. This reduces accidental exposure and also makes failures clearer: if it’s not enabled, it won’t show up.

Joke #1: If you keep exposedByDefault=true, you’re not running a reverse proxy—you’re running a surprise generator.

Canonical Compose example that avoids silent failures

This pattern has fewer moving parts and fails louder:

cr0x@server:~$ cat docker-compose.yml
version: "3.9"

networks:
  edge:
    external: true

services:
  traefik:
    image: traefik:v2.11
    command:
      - --api.dashboard=true
      - --api.insecure=false
      - --entrypoints.web.address=:80
      - --entrypoints.websecure.address=:443
      - --providers.docker=true
      - --providers.docker.exposedbydefault=false
      - --providers.docker.network=edge
      - --log.level=INFO
      - --accesslog=true
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - /var/run/docker.sock:/var/run/docker.sock:ro
    networks:
      - edge
    labels:
      - "traefik.enable=true"
      - "traefik.http.routers.traefik.rule=Host(`traefik.example.com`)"
      - "traefik.http.routers.traefik.entrypoints=websecure"
      - "traefik.http.routers.traefik.tls=true"
      - "traefik.http.routers.traefik.service=api@internal"

  app:
    image: ghcr.io/example/app:latest
    environment:
      - PORT=8080
    networks:
      - edge
    labels:
      - "traefik.enable=true"

      - "traefik.http.routers.app.rule=Host(`app.example.com`)"
      - "traefik.http.routers.app.entrypoints=websecure"
      - "traefik.http.routers.app.tls=true"
      - "traefik.http.routers.app.service=app-svc"

      - "traefik.http.services.app-svc.loadbalancer.server.port=8080"

      - "traefik.http.middlewares.app-headers.headers.framedeny=true"
      - "traefik.http.routers.app.middlewares=app-headers"

Notice what’s explicit:

• Traefik uses a specific Docker network (--providers.docker.network=edge).
• The app service port is pinned to 8080.
• Router/service/middleware names are stable and referenced explicitly.
• Traefik itself is routed via api@internal, which reduces “why does the dashboard not work?” confusion.

Practical tasks: commands, outputs, and decisions (12+)

These are the checks I actually run. Each task includes: command, typical output, what it means, and the decision you make.

Task 1: Confirm Traefik container is running and which image/version

cr0x@server:~$ docker ps --format 'table {{.Names}}\t{{.Image}}\t{{.Status}}\t{{.Ports}}'
NAMES      IMAGE          STATUS          PORTS
traefik    traefik:v2.11  Up 2 hours      0.0.0.0:80->80/tcp, 0.0.0.0:443->443/tcp
app        ghcr.io/example/app:latest  Up 2 hours

Meaning: Traefik is running and binding :80/:443 on the host.

Decision: If Traefik isn’t up or ports aren’t mapped, stop. Fix container lifecycle or host firewall before touching labels.

Task 2: Inspect Traefik startup flags (providers, exposedByDefault, network)

cr0x@server:~$ docker inspect traefik --format '{{json .Config.Cmd}}'
["--api.dashboard=true","--entrypoints.web.address=:80","--entrypoints.websecure.address=:443","--providers.docker=true","--providers.docker.exposedbydefault=false","--providers.docker.network=edge","--log.level=INFO","--accesslog=true"]

Meaning: Docker provider is on, default exposure is off, and Traefik will look for backends on the edge network.

Decision: If --providers.docker.network is set, your app must be attached to that network or routing will fail.

Task 3: Verify the app container is on the same Docker network Traefik expects

cr0x@server:~$ docker inspect app --format '{{json .NetworkSettings.Networks}}'
{"edge":{"IPAMConfig":null,"Links":null,"Aliases":["app","3e9c1b7b4a2d"],"MacAddress":"02:42:ac:18:00:05","DriverOpts":null,"NetworkID":"b7b9d6c3b34a","EndpointID":"f2b59b5f8e67","Gateway":"172.24.0.1","IPAddress":"172.24.0.5","IPPrefixLen":16,"IPv6Gateway":"","GlobalIPv6Address":"","GlobalIPv6PrefixLen":0,"DNSNames":["app","3e9c1b7b4a2d"]}}

Meaning: App is on edge with an IP Traefik can route to.

Decision: If the app is not on that network, add it. Don’t “just open a port” unless you want to bypass your proxy entirely.

Task 4: Confirm the labels Traefik will read (and spot typos fast)

cr0x@server:~$ docker inspect app --format '{{json .Config.Labels}}' | jq -r 'to_entries[] | "\(.key)=\(.value)"' | sort
traefik.enable=true
traefik.http.routers.app.entrypoints=websecure
traefik.http.routers.app.rule=Host(`app.example.com`)
traefik.http.routers.app.service=app-svc
traefik.http.routers.app.tls=true
traefik.http.routers.app.middlewares=app-headers
traefik.http.middlewares.app-headers.headers.framedeny=true
traefik.http.services.app-svc.loadbalancer.server.port=8080

Meaning: Labels are present and spelled correctly. You can now reason about Traefik config deterministically.

Decision: If you see traefik.http.router (missing “s”), or mismatched names, fix labels before touching anything else.

Task 5: Check Traefik logs for provider errors (parsing, missing middleware)

cr0x@server:~$ docker logs traefik --since 15m | tail -n 20
time="2026-01-03T09:18:41Z" level=info msg="Configuration loaded from flags."
time="2026-01-03T09:21:10Z" level=info msg="Skipping same configuration for provider docker"
time="2026-01-03T09:22:07Z" level=error msg="middleware \"app-auth@docker\" does not exist" routerName=app@docker entryPointName=websecure
time="2026-01-03T09:22:07Z" level=error msg="error while adding middleware: middleware \"app-auth@docker\" does not exist" entryPointName=websecure routerName=app@docker

Meaning: Router exists, but references a middleware that doesn’t. This often still routes, just without the middleware, which is its own kind of “silent fail.”

Decision: Either define the middleware label or remove it from the router. Don’t leave broken references around; they rot into security bugs.

Task 6: Validate that routers exist by querying Traefik API (inside container)

cr0x@server:~$ docker exec -it traefik sh -lc 'wget -qO- http://127.0.0.1:8080/api/http/routers | head -n 20'
[{"entryPoints":["websecure"],"service":"app-svc@docker","rule":"Host(`app.example.com`)","status":"enabled","using":["websecure"],"name":"app@docker"},{"entryPoints":["websecure"],"service":"api@internal","rule":"Host(`traefik.example.com`)","status":"enabled","using":["websecure"],"name":"traefik@docker"}]

Meaning: Your router is real in Traefik’s dynamic config, not just in your imagination.

Decision: If your router is missing here, Traefik didn’t load it. That’s a label problem, provider constraint, or exposure setting problem.

Task 7: Confirm the service port Traefik will use

cr0x@server:~$ docker exec -it traefik sh -lc 'wget -qO- http://127.0.0.1:8080/api/http/services | jq -r ".[] | select(.name==\"app-svc@docker\") | .loadBalancer.servers"'
[
  {
    "url": "http://172.24.0.5:8080"
  }
]

Meaning: Traefik points to the right IP and port.

Decision: If you see the wrong port (often 80), explicitly set loadbalancer.server.port and redeploy.

Task 8: Test the backend directly from the Traefik container (network path check)

cr0x@server:~$ docker exec -it traefik sh -lc 'wget -qSO- http://172.24.0.5:8080/health -O /dev/null'
  HTTP/1.1 200 OK
  Content-Type: application/json
  Date: Sat, 03 Jan 2026 09:25:01 GMT
  Content-Length: 17

Meaning: Connectivity is fine; failures are in routing/matching/TLS/middleware, not network reachability.

Decision: If this fails, fix Docker networking, container listening port, or application binding (0.0.0.0 vs 127.0.0.1).

Task 9: Verify that the request Host header matches the router rule

cr0x@server:~$ curl -sS -D- -o /dev/null -H 'Host: app.example.com' http://127.0.0.1/
HTTP/1.1 301 Moved Permanently
Location: https://app.example.com/
Date: Sat, 03 Jan 2026 09:25:28 GMT
Content-Length: 17
Content-Type: text/plain; charset=utf-8

Meaning: Something matched on HTTP and likely redirected to HTTPS (either via middleware or entrypoint redirection).

Decision: If you get 404 here, the router rule didn’t match. Re-check Host rule quoting, domain, and entrypoints.

Task 10: Confirm HTTPS routing and certificate behavior (SNI matters)

cr0x@server:~$ curl -sS -D- -o /dev/null https://app.example.com/
HTTP/2 200
content-type: text/html; charset=utf-8
date: Sat, 03 Jan 2026 09:26:02 GMT
server: traefik

Meaning: TLS works and router matches on websecure.

Decision: If TLS handshake fails or you see the wrong certificate, check router TLS flags, certresolver, and whether you’re hitting the correct Traefik instance.

Task 11: Detect rule conflicts and priority issues

cr0x@server:~$ docker exec -it traefik sh -lc 'wget -qO- http://127.0.0.1:8080/api/http/routers | jq -r ".[] | [.name,.rule,(.priority|tostring)] | @tsv" | sort -k2'
app@docker	Host(`app.example.com`)	
catchall@docker	HostRegexp(`{any:.+}`)	1

Meaning: You have a catch-all router that can steal traffic if priority is higher or if your app router doesn’t match precisely.

Decision: Set explicit priorities. Don’t rely on “it probably sorts itself out.” It won’t.

Task 12: Check Docker events to see if Traefik is even noticing container changes

cr0x@server:~$ docker events --since 5m --filter type=container --filter event=start
2026-01-03T09:24:10.128722391Z container start 3e9c1b7b4a2d (image=ghcr.io/example/app:latest, name=app)

Meaning: Docker is emitting lifecycle events; Traefik should pick them up if it has access to the socket.

Decision: If Traefik isn’t updating, confirm the Docker socket mount is present and read permissions are sufficient.

Task 13: Confirm Traefik can read the Docker socket (common in hardened setups)

cr0x@server:~$ docker exec -it traefik sh -lc 'ls -l /var/run/docker.sock'
srw-rw----    1 root     docker           0 Jan  3 08:01 /var/run/docker.sock

Meaning: Socket exists. Permissions may still be an issue depending on Traefik’s user.

Decision: If Traefik runs as non-root and can’t read this socket, you’ll see provider errors and missing routers. Fix user/group or run with appropriate permissions.

Task 14: Validate the Compose file you actually deployed (not the one you edited)

cr0x@server:~$ docker compose config | sed -n '1,120p'
services:
  app:
    image: ghcr.io/example/app:latest
    labels:
      traefik.enable: "true"
      traefik.http.routers.app.entrypoints: websecure
      traefik.http.routers.app.rule: Host(`app.example.com`)
      traefik.http.routers.app.service: app-svc
      traefik.http.routers.app.tls: "true"
      traefik.http.services.app-svc.loadbalancer.server.port: "8080"
networks:
  edge:
    external: true

Meaning: This is the rendered configuration after Compose merges, env interpolation, and YAML parsing. It’s the truth.

Decision: If the rendered labels differ (missing quotes, truncated strings), fix the Compose source. Debugging the wrong file is a classic self-own.

Three corporate-world mini-stories

Mini-story 1: The incident caused by a wrong assumption

They were migrating a customer-facing app from a hand-written Nginx config to Traefik with Docker labels. The plan looked good: every service had labels, and there was a tidy “edge” network. Someone even wrote a README, which is how you know this was going to hurt.

The wrong assumption: “If the container is reachable from the host, Traefik can reach it too.” They exposed the app on 0.0.0.0:8080 for testing and confirmed it worked via curl http://host:8080. Then they removed the port mapping because “Traefik handles ingress now.”

Production deploy: Traefik returned 404 for the hostname. People chased DNS, then certificates, then “maybe the load balancer.” Meanwhile, the service was healthy and logs were calm. The app team started suggesting rollbacks. The platform team started suggesting prayer.

The issue was boring: Traefik was configured with --providers.docker.network=edge, but the app container was only attached to the default Compose network. Traefik never saw an endpoint it could use. No network, no service, no route.

The fix took five minutes: attach the app to edge and redeploy. The postmortem took longer, because the hard part wasn’t the fix; it was admitting they’d been “testing” a different network path than production uses.

Mini-story 2: The optimization that backfired

A different company had a “labels must be minimal” initiative. The reasoning wasn’t crazy: too many labels are hard to read, and copy-paste errors are real. So they removed explicit service port labels, relying on Traefik’s auto port detection. It worked for most services. That’s the trap: partial success is the most expensive form of failure.

Later, one service added a second exposed port for metrics. Docker now showed two candidates. Traefik picked one. It was the wrong one. Requests routed to the metrics endpoint, which responded quickly but not usefully. Clients saw 404s and “not found” responses. Nothing was technically down; everything was practically broken.

The on-call initially blamed a bad deploy. Rollback didn’t help because the metrics port exposure stayed. They blamed Traefik. They bumped resources. They changed timeouts. They added retries (which made it noisier).

The real fix was to undo the “optimization” and pin the service port label. The lesson wasn’t “auto-detection is bad.” The lesson was: in production, ambiguity is a bug you haven’t met yet.

Mini-story 3: The boring but correct practice that saved the day

A fintech team had a habit that looked annoyingly ceremonial: every reverse-proxy change required a “route rehearsal” in staging, including a scripted query of Traefik’s routers and services APIs. They didn’t rely on the dashboard. They didn’t rely on eyeballing labels. They ran a script and archived the output with the change ticket.

During a routine deploy, a developer renamed a router from billing to billing-app but forgot to update the middleware reference. Traefik logged an error about the missing middleware, but the route still served traffic—just without an auth middleware that enforced internal-only access.

In many orgs, that’s how you end up with a security incident that starts with “we didn’t think it was reachable.” Here, the staging rehearsal caught it because their script asserted that the router had the expected middleware chain attached.

They fixed the label before it hit production. The boring ritual looked like bureaucracy right up until it prevented an incident that would have been expensive and humiliating. This is what “reliability culture” looks like when it’s actually doing work.

Common mistakes: symptom → root cause → fix

These are the repeat offenders. If Traefik “silently fails,” it’s usually one of these wearing a fake mustache.

1) Symptom: 404 from Traefik for the correct hostname

Root cause: Router rule doesn’t match (wrong domain, wrong quoting, using Host() but client sends different Host header), or router bound to wrong entrypoint.

Fix: Verify router exists in API, then compare rule to an actual request. Ensure traefik.http.routers.<name>.entrypoints includes the entrypoint you’re hitting.

2) Symptom: Router missing entirely in dashboard/API

Root cause: traefik.enable missing while exposedByDefault=false; or Docker provider constraints exclude it; or label keys malformed.

Fix: Add traefik.enable=true; check provider flags; validate labels via docker inspect and docker compose config.

3) Symptom: Router exists, but requests go to the wrong service

Root cause: Service name collision, implicit service selection, or multiple routers pointing to a shared default service by accident.

Fix: Set traefik.http.routers.<router>.service=<service> explicitly and use unique service names per app.

4) Symptom: TLS works sometimes; sometimes you get the default certificate

Root cause: Router isn’t bound to websecure or tls=true is missing; or SNI mismatch; or multiple Traefik instances behind a load balancer.

Fix: Ensure router has entrypoints=websecure and tls=true. Confirm the client uses the correct hostname and hits the intended instance.

5) Symptom: Middleware “not applied,” but routing works

Root cause: Middleware name mismatch, provider scope mismatch (@docker vs @file), or middleware defined on another container and not referenced correctly.

Fix: Check Traefik logs for “middleware does not exist.” Use a single source of truth: define middlewares alongside routers or in a file provider and reference with suffix.

6) Symptom: 502 Bad Gateway from Traefik

Root cause: Traefik matches the router but cannot reach upstream (wrong network, wrong port, app listening on localhost only, container restarting).

Fix: Test from Traefik container to upstream IP:port. Pin service port. Ensure app binds to 0.0.0.0.

7) Symptom: Everything works on HTTP, fails on HTTPS

Root cause: Router only defined for web, or HTTPS router missing TLS config / certresolver.

Fix: Create a dedicated websecure router, set tls=true, and ensure certificate resolver is configured if needed.

8) Symptom: You changed labels but Traefik behavior didn’t change

Root cause: You edited the Compose file but didn’t redeploy; or Traefik didn’t pick up events due to socket permissions; or you’re looking at the wrong Traefik instance.

Fix: Redeploy the service; check Docker events; check Traefik logs for provider refresh; confirm target instance with access logs.

Joke #2: Traefik doesn’t “ignore” your labels. It just interprets them in a way that makes your future self file a complaint.

Checklists / step-by-step plan

Step-by-step: Make a label-based route that won’t silently fail

1. Choose a single Docker network for edge traffic (e.g., edge). Put Traefik and every routed service on it.
2. Set Traefik provider behavior explicitly:
   • --providers.docker=true
   • --providers.docker.exposedbydefault=false
   • --providers.docker.network=edge
3. For each service:
   • Add traefik.enable=true.
   • Create a router with a stable name: traefik.http.routers.<router>.*.
   • Bind it to the correct entrypoint(s).
   • Set tls=true for HTTPS routers.
   • Set service=<service-name> explicitly.
   • Set loadbalancer.server.port explicitly.
4. Run docker compose config and verify the rendered labels are correct.
5. Verify routers and services via Traefik API after deploy.
6. Test from inside Traefik container to the upstream IP:port.
7. Only then debug TLS/certs/middlewares.

Checklist: Before you blame Traefik

• Container and Traefik share a network that Traefik is configured to use.
• Router exists in Traefik API.
• Router rule matches the request’s Host and Path.
• Router is bound to the entrypoint receiving the request.
• Service port is pinned and correct.
• Upstream is reachable from Traefik container.
• No catch-all router is stealing traffic due to priority.
• Middleware references exist and are correctly scoped.

FAQ

1) Why do I get a Traefik 404 instead of an error when labels are wrong?

Because 404 is the correct response when no router matches the request. A missing router isn’t a runtime exception; it’s absent configuration.

2) My router exists, but it still doesn’t match. What’s the fastest way to prove it?

Send a request with an explicit Host header to the same entrypoint you’re testing, then compare with the router rule from Traefik’s API.

3) Do I really need to quote label values in Docker Compose?

Yes. YAML parsing and special characters (backticks, commas, colons) are where “it worked on my laptop” is born. Quote them and move on with your life.

4) When should I use PathPrefix vs Path?

Path matches exactly. PathPrefix matches a subtree. For APIs, PathPrefix(`/api`) is common. Be explicit, and avoid accidental overlaps with other routers.

5) Why does Traefik route to the wrong port?

Auto-detection. If Docker exposes multiple ports (or the image declares multiple), Traefik picks one. Pin the port with loadbalancer.server.port.

6) What’s the difference between web/websecure and ports 80/443?

web and websecure are entrypoint names. They usually correspond to ports, but it’s the name that routers bind to. You can map entrypoints to any port.

7) Why does middleware sometimes “half-fail” without breaking routing?

Traefik can attach what exists and log errors for what doesn’t. That’s great for availability, but dangerous for security controls. Treat middleware errors as deploy failures.

8) Should I put all middlewares on the Traefik container to centralize config?

Only if you’re disciplined. Centralizing can reduce duplication, but it also increases blast radius and encourages tangled dependencies. For small stacks, keep middlewares near the services they affect.

9) Is the Traefik dashboard safe to expose?

Not by default. Route it through websecure, add auth middleware, and avoid api.insecure=true in production. Treat it like an admin interface—because it is.

10) How do I stop accidental exposure of random containers?

Set exposedByDefault=false and require traefik.enable=true. Then use a CI check that fails if a service lacks explicit router/service/port labels.

Next steps you can do today

If Traefik route rules are “silently failing,” the fix is rarely magic. It’s hygiene:

1. Make routing explicit: router names, service names, entrypoints, TLS flags, and upstream port.
2. Standardize your label pattern so every service looks the same. Consistency is a debugging tool.
3. Adopt the fast diagnosis order: entrypoint → router existence → match → upstream reachability → middleware/TLS.
4. Add one boring guardrail: a scripted check that queries Traefik’s routers/services after deploy and asserts expected rules and ports.

When Traefik is configured cleanly, it’s not mysterious. It’s a request router with strong opinions and weak patience. Meet it halfway: be explicit, verify via API, and stop trusting what “should” work.