Unable to bring up Jenkins using Helm

12/9/2020

I'm following the doc in Jenkins page, I'm running with 2 node K8s cluster (1 master 1 worker), setting service type to nodeport, for some reason the init container crashes and never comes up.

    kubectl describe pod jenkins-0 -n jenkins
Name:         jenkins-0
Namespace:    jenkins
Priority:     0
Node:         vlab048009.dom047600.lab/10.204.110.35
Start Time:   Wed, 09 Dec 2020 23:19:59 +0530
Labels:       app.kubernetes.io/component=jenkins-controller
              app.kubernetes.io/instance=jenkins
              app.kubernetes.io/managed-by=Helm
              app.kubernetes.io/name=jenkins
              controller-revision-hash=jenkins-c5795f65f
              statefulset.kubernetes.io/pod-name=jenkins-0
Annotations:  checksum/config: 2a4c2b3ea5dea271cb7c0b8e8582b682814d39f8e933e0348725b0b9a7dbf258
Status:       Pending
IP:           10.244.1.28
IPs:
  IP:           10.244.1.28
Controlled By:  StatefulSet/jenkins
Init Containers:
  init:
    Container ID:  docker://95e3298740bcaed3c2adf832f41d346e563c92add728080cfdcfcac375e0254d
    Image:         jenkins/jenkins:lts
    Image ID:      docker-pullable://jenkins/jenkins@sha256:1433deaac433ce20c534d8b87fcd0af3f25260f375f4ee6bdb41d70e1769d9ce
    Port:          <none>
    Host Port:     <none>
    Command:
      sh
      /var/jenkins_config/apply_config.sh
    State:          Waiting
      Reason:       CrashLoopBackOff
    Last State:     Terminated
      Reason:       Error
      Exit Code:    1
      Started:      Wed, 09 Dec 2020 23:41:28 +0530
      Finished:     Wed, 09 Dec 2020 23:41:29 +0530
    Ready:          False
    Restart Count:  9
    Limits:
      cpu:     2
      memory:  4Gi
    Requests:
      cpu:        50m
      memory:     256Mi
    Environment:  <none>
    Mounts:
      /usr/share/jenkins/ref/plugins from plugins (rw)
      /var/jenkins_config from jenkins-config (rw)
      /var/jenkins_home from jenkins-home (rw)
      /var/jenkins_plugins from plugin-dir (rw)
      /var/run/secrets/kubernetes.io/serviceaccount from jenkins-token-ppfw7 (ro)
Containers:
  jenkins:
    Container ID:
    Image:         jenkins/jenkins:lts
    Image ID:
    Ports:         8080/TCP, 50000/TCP
    Host Ports:    0/TCP, 0/TCP
    Args:
      --httpPort=8080
    State:          Waiting
      Reason:       PodInitializing
    Ready:          False
    Restart Count:  0
    Limits:
      cpu:     2
      memory:  4Gi
    Requests:
      cpu:      50m
      memory:   256Mi
    Liveness:   http-get http://:http/login delay=0s timeout=5s period=10s #success=1 #failure=5
    Readiness:  http-get http://:http/login delay=0s timeout=5s period=10s #success=1 #failure=3
    Startup:    http-get http://:http/login delay=0s timeout=5s period=10s #success=1 #failure=12
    Environment:
      POD_NAME:                  jenkins-0 (v1:metadata.name)
      JAVA_OPTS:                 -Dcasc.reload.token=$(POD_NAME)
      JENKINS_OPTS:
      JENKINS_SLAVE_AGENT_PORT:  50000
      CASC_JENKINS_CONFIG:       /var/jenkins_home/casc_configs
    Mounts:
      /run/secrets/chart-admin-password from admin-secret (ro,path="jenkins-admin-password")
      /run/secrets/chart-admin-username from admin-secret (ro,path="jenkins-admin-user")
      /usr/share/jenkins/ref/plugins/ from plugin-dir (rw)
      /var/jenkins_config from jenkins-config (ro)
      /var/jenkins_home from jenkins-home (rw)
      /var/jenkins_home/casc_configs from sc-config-volume (rw)
      /var/run/secrets/kubernetes.io/serviceaccount from jenkins-token-ppfw7 (ro)
  config-reload:
    Container ID:
    Image:          kiwigrid/k8s-sidecar:0.1.275
    Image ID:
    Port:           <none>
    Host Port:      <none>
    State:          Waiting
      Reason:       PodInitializing
    Ready:          False
    Restart Count:  0
    Environment:
      POD_NAME:           jenkins-0 (v1:metadata.name)
      LABEL:              jenkins-jenkins-config
      FOLDER:             /var/jenkins_home/casc_configs
      NAMESPACE:          jenkins
      REQ_URL:            http://localhost:8080/reload-configuration-as-code/?casc-reload-token=$(POD_NAME)
      REQ_METHOD:         POST
      REQ_RETRY_CONNECT:  10
    Mounts:
      /var/jenkins_home from jenkins-home (rw)
      /var/jenkins_home/casc_configs from sc-config-volume (rw)
      /var/run/secrets/kubernetes.io/serviceaccount from jenkins-token-ppfw7 (ro)
Conditions:
  Type              Status
  Initialized       False
  Ready             False
  ContainersReady   False
  PodScheduled      True
Volumes:
  plugins:
    Type:       EmptyDir (a temporary directory that shares a pod's lifetime)
    Medium:
    SizeLimit:  <unset>
  jenkins-config:
    Type:      ConfigMap (a volume populated by a ConfigMap)
    Name:      jenkins
    Optional:  false
  plugin-dir:
    Type:       EmptyDir (a temporary directory that shares a pod's lifetime)
    Medium:
    SizeLimit:  <unset>
  jenkins-home:
    Type:       EmptyDir (a temporary directory that shares a pod's lifetime)
    Medium:
    SizeLimit:  <unset>
  sc-config-volume:
    Type:       EmptyDir (a temporary directory that shares a pod's lifetime)
    Medium:
    SizeLimit:  <unset>
  admin-secret:
    Type:        Secret (a volume populated by a Secret)
    SecretName:  jenkins
    Optional:    false
  jenkins-token-ppfw7:
    Type:        Secret (a volume populated by a Secret)
    SecretName:  jenkins-token-ppfw7
    Optional:    false
QoS Class:       Burstable
Node-Selectors:  <none>
Tolerations:     node.kubernetes.io/not-ready:NoExecute op=Exists for 300s
                 node.kubernetes.io/unreachable:NoExecute op=Exists for 300s
Events:
  Type     Reason     Age                  From               Message
  ----     ------     ----                 ----               -------
  Normal   Scheduled  22m                  default-scheduler  Successfully assigned jenkins/jenkins-0 to vlab048009.dom047600.lab
  Normal   Pulled     22m                  kubelet            Successfully pulled image "jenkins/jenkins:lts" in 4.648858149s
  Normal   Pulled     21m                  kubelet            Successfully pulled image "jenkins/jenkins:lts" in 1.407161762s
  Normal   Pulled     21m                  kubelet            Successfully pulled image "jenkins/jenkins:lts" in 4.963056101s
  Normal   Created    21m (x4 over 22m)    kubelet            Created container init
  Normal   Started    21m (x4 over 22m)    kubelet            Started container init
  Normal   Pulled     21m                  kubelet            Successfully pulled image "jenkins/jenkins:lts" in 8.0749493s
  Normal   Pulling    20m (x5 over 22m)    kubelet            Pulling image "jenkins/jenkins:lts"
  Warning  BackOff    2m1s (x95 over 21m)  kubelet            Back-off restarting failed container
-- Sanjay M. P.
jenkins
kubernetes
kubernetes-helm

1 Answer

12/14/2020

Firstly make sure that you had executed command:

$ helm repo update

Execute also command:

$ kubectl logs <pod-name> -c <init-container-name>

to inspect init container. Then you will be able to properly debug this setup.

This might be a connection issue to the Jenkins update site. You can build an image which contains required plugins and disable plugin download. Take a look: jenkins-kubernetes.

See more: jenkins-helm-issues - in this case problem lays in plug-in compatibility.

-- Malgorzata
Source: StackOverflow