faas-netes getting 502 'Error pulling metrics from provider/backend'


You can’t deploy faas-netes in your own namespace, you need to deploy it in the default namespace. It seems that the [https://github.com/openfaas/faas-netes/blob/32a818328921900f250501f1e117d1aee551b85b/faas.yml#L79](DNS lookup is fully specified) including the default namespace. If you want to use other namespaces, it seems that using the [https://github.com/openfaas/faas-netes/blob/master/HELM.md](Helm chart) is your best bet at the time of writing.


I’ve been playing with OpenFaaS and specifically faas-netes; the deployment of OpenFaaS on Kubernetes.

I deployed to my cluster with the following:

kubectl create namespace openfaas
kubectl apply -n openfaas -f https://raw.githubusercontent.com/openfaas/faas-netes/master/faas.yml,https://raw.githubusercontent.com/openfaas/faas-netes/master/monitoring.yml,https://raw.githubusercontent.com/openfaas/faas-netes/master/rbac.yml

Then I opened up the web UI and looked at the network traffic in developer tools and was seeing every AJAX call to ‘/system/functions` in the network logs getting a 502 error. Hmm, that’s weird.

I tried using faas-cli and that wasn’t going well either. It was also getting 500 HTTP response codes.

Looking at the logs for the gateway pod, I could see the error:

2017/11/09 05:09:13 http: proxy error: dial tcp: lookup faas-netesd.default.svc.cluster.local on dial udp i/o timeout
2017/11/09 05:09:13 < [http://faas-netesd.default.svc.cluster.local:8080/system/functions] - 502 took 2.650294 seconds
502 Error pulling metrics from provider/backend

The solution

You can see that the DNS lookup that the gateway pod was attempting is faas-netesd.default.svc.cluster.local. This second part of that means that it’s looking in the default namespace. That’s not the openfaas namespace that I deployed to. Now it’s starting to make sense. If you look at the YAML for the faas-netes service, you’ll see that the [https://github.com/openfaas/faas-netes/blob/32a818328921900f250501f1e117d1aee551b85b/faas.yml#L79](DNS lookup is fully specified).

The problem is I was rebellious and didn’t follow the instructions that said to deploy to the default namespace.

The solution is to deploy to the default namespace. So don’t create your own namespace and deploy to it, just do:

kubectl apply -f https://raw.githubusercontent.com/openfaas/faas-netes/master/faas.yml,https://raw.githubusercontent.com/openfaas/faas-netes/master/monitoring.yml,https://raw.githubusercontent.com/openfaas/faas-netes/master/rbac.yml

I think this was a conscious choice to address things like [https://github.com/openfaas/faas-netes/issues/12](DOS-ing the DNS service).

Most people probably won’t have this problem because they’ll follow the instructions but for those that do experience this problem and google for the error message, I hope this has helped you.

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