GCP Kubernetes workload "Does not have minimum availability"

Question

Background: I'm trying to set up a Bitcoin Core regtest pod on Google Cloud Platform. I borrowed some code from https://gist.github.com/zquestz/0007d1ede543478d44556280fdf238c9, editing it so that instead of using Bitcoin ABC (a different client implementation), it uses Bitcoin Core instead, and changed the RPC username and password to both be "test". I also added some command arguments for the docker-entrypoint.sh script to forward to bitcoind, the daemon for the nodes I am running. When attempting to deploy the following three YAML files, the dashboard in "workloads" shows bitcoin has not having minimum availability. Getting the pod to deploy correctly is important so I can send RPC commands to the Load Balancer. Attached below are my YAML files being used. I am not very familiar with Kubernetes, and I'm doing a research project on scalability which entails running RPC commands against this pod. Ask for relevant logs and I will provide them in seperate pastebins. Right now, I'm only running three machines on my cluster, as I'm am still setting this up. The zone is us-east1-d, machine type is n1-standard-2.

Question: Given these files below, what is causing GCP Kubernetes Engine to respond with "Does not have minimum availability", and how can this be fixed?

---

bitcoin-deployment.sh

apiVersion: extensions/v1beta1
kind: Deployment
metadata:
  namespace: default
  labels:
    service: bitcoin
  name: bitcoin
spec:
  strategy:
    type: Recreate
  replicas: 1
  template:
    metadata:
      labels:
        service: bitcoin
    spec:
      containers:
      - env:
        - name: BITCOIN_RPC_USER
          valueFrom:
            secretKeyRef:
              name: test
              key: test
        - name: BITCOIN_RPC_PASSWORD
          valueFrom:
            secretKeyRef:
              name: test
              key: test
        image: ruimarinho/bitcoin-core:0.17.0
        name: bitcoin
        ports:
        - containerPort: 18443
          protocol: TCP
        volumeMounts:
          - mountPath: /data
            name: bitcoin-data
        resources:
          requests:
            memory: "1.5Gi"
        command: ["./entrypoint.sh"]
        args: ["-server", "-daemon", "-regtest", "-rpcbind=127.0.0.1", "-rpcallowip=0.0.0.0/0", "-rpcport=18443", "-rpcuser=test", "-rpcpassport=test"]
      restartPolicy: Always
      volumes:
        - name: bitcoin-data
          gcePersistentDisk:
            pdName: disk-bitcoincore-1
            fsType: ext4

---

bitcoin-secrets.yml

apiVersion: v1
kind: Secret
metadata:
  name: bitcoin
type: Opaque
data:
  rpcuser: dGVzdAo=
  rpcpass: dGVzdAo=

---

bitcoin-srv.yml

apiVersion: v1
kind: Service
metadata:
  name: bitcoin
  namespace: default
spec:
  ports:
    - port: 18443
      targetPort: 18443
  selector:
    service: bitcoin
  type: LoadBalancer
  externalTrafficPolicy: Local

Answer 1

I have run into this issue several times. The solutions that I used:

1. Wait. Google Cloud does not have enough resource available in the Region/Zone that you are trying to launch into. In some cases this took an hour to an entire day.
2. Select a different Region/Zone.

An example was earlier this month. I could not launch new resources in us-west1-a. I think just switched to us-east4-c. Everything launched.

I really do not know why this happens under the covers with Google. I have personally experienced this problem three times in the last three months and I have seen this problem several times on StackOverflow. The real answer might be a simple is that Google Cloud is really started to grow faster than their infrastructure. This is a good thing for Google as I know that they are investing in major new reasources for the cloud. Personally, I really like working with their cloud.

Answer 2

There could be many reasons for this failure:

1. Insufficient resources
2. Liveliness probe failure
3. Readiness probe failure