Kubeye

Kubeye aims to find various problems on Kubernetes, such as application misconfiguration, cluster components unhealthy and node problems(using Node-Problem-Detector). Besides predefined rules, it also supports custom defined rules.

Architecture

Kubeye gets cluster diagnostic data by calling the Kubernetes API, by regular matching of key error messages in logs and by rule matching of container syntax. See Architecture for details.

How to use

• Install Kubeye on your machine

  • Download pre built executables from Releases.

  • Or you can build from source code

  git clone https://github.com/kubesphere/kubeye.git
  cd kubeye 
  make install
  

• [Optional] Install Node-problem-Detector

Note: This line will install npd on your cluster, only required if you want detailed report.

ke install npd

• Run kubeye

root@node1:# ke diags
NODENAME   SEVERITY   HEARTBEATTIME               REASON              MESSAGE
node18     Fatal     2020-11-19T10:32:03+08:00   NodeStatusUnknown   Kubelet stopped posting node status.
node19     Fatal     2020-11-19T10:31:37+08:00   NodeStatusUnknown   Kubelet stopped posting node status.
node2      Fatal     2020-11-19T10:31:14+08:00   NodeStatusUnknown   Kubelet stopped posting node status.
node3      Fatal     2020-11-27T17:36:53+08:00   KubeletNotReady     Container runtime not ready: RuntimeReady=false reason:DockerDaemonNotReady message:docker: failed to get docker version: Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?

NAME        SEVERITY   TIME                        MESSAGE
scheduler   Fatal     2020-11-27T17:09:59+08:00   Get http://127.0.0.1:10251/healthz: dial tcp 127.0.0.1:10251: connect: connection refused
etcd-0      Fatal     2020-11-27T17:56:37+08:00   Get https://192.168.13.8:2379/health: dial tcp 192.168.13.8:2379: connect: connection refused

NAMESPACE       SEVERITY   PODNAME                                          EVENTTIME                   REASON                MESSAGE
default         Warning    node3.164b53d23ea79fc7                           2020-11-27T17:37:34+08:00   ContainerGCFailed     rpc error: code = Unknown desc = Cannot connect to the Docker daemon at unix:///var/run/docker.sock. Is the docker daemon running?
default         Warning    node3.164b553ca5740aae                           2020-11-27T18:03:31+08:00   FreeDiskSpaceFailed   failed to garbage collect required amount of images. Wanted to free 5399374233 bytes, but freed 416077545 bytes
default         Warning    nginx-b8ffcf679-q4n9v.16491643e6b68cd7           2020-11-27T17:09:24+08:00   Failed                Error: ImagePullBackOff
default         Warning    node3.164b5861e041a60e                           2020-11-27T19:01:09+08:00   SystemOOM             System OOM encountered, victim process: stress, pid: 16713
default         Warning    node3.164b58660f8d4590                           2020-11-27T19:01:27+08:00   OOMKilling            Out of memory: Kill process 16711 (stress) score 205 or sacrifice child Killed process 16711 (stress), UID 0, total-vm:826516kB, anon-rss:819296kB, file-rss:0kB, shmem-rss:0kB
insights-agent  Warning    workloads-1606467120.164b519ca8c67416            2020-11-27T16:57:05+08:00   DeadlineExceeded      Job was active longer than specified deadline
kube-system     Warning    calico-node-zvl9t.164b3dc50580845d               2020-11-27T17:09:35+08:00   DNSConfigForming      Nameserver limits were exceeded, some nameservers have been omitted, the applied nameserver line is: 100.64.11.3 114.114.114.114 119.29.29.29
kube-system     Warning    kube-proxy-4bnn7.164b3dc4f4c4125d                2020-11-27T17:09:09+08:00   DNSConfigForming      Nameserver limits were exceeded, some nameservers have been omitted, the applied nameserver line is: 100.64.11.3 114.114.114.114 119.29.29.29
kube-system     Warning    nodelocaldns-2zbhh.164b3dc4f42d358b              2020-11-27T17:09:14+08:00   DNSConfigForming      Nameserver limits were exceeded, some nameservers have been omitted, the applied nameserver line is: 100.64.11.3 114.114.114.114 119.29.29.29


NAMESPACE       SEVERITY     NAME                      KIND         TIME                        MESSAGE
kube-system     Warning      node-problem-detector     DaemonSet    2020-11-27T17:09:59+08:00   [livenessProbeMissing runAsPrivileged]
kube-system     Warning      calico-node               DaemonSet    2020-11-27T17:09:59+08:00   [runAsPrivileged cpuLimitsMissing]
kube-system     Warning      nodelocaldns              DaemonSet    2020-11-27T17:09:59+08:00   [cpuLimitsMissing runAsPrivileged]
default         Warning      nginx                     Deployment   2020-11-27T17:09:59+08:00   [cpuLimitsMissing livenessProbeMissing tagNotSpecified]
insights-agent  Warning      workloads                 CronJob      2020-11-27T17:09:59+08:00   [livenessProbeMissing]
insights-agent  Warning      cronjob-executor          Job          2020-11-27T17:09:59+08:00   [livenessProbeMissing]
kube-system     Warning      calico-kube-controllers   Deployment   2020-11-27T17:09:59+08:00   [cpuLimitsMissing livenessProbeMissing]
kube-system     Warning      coredns                   Deployment   2020-11-27T17:09:59+08:00   [cpuLimitsMissing]   

You can refer to the FAQ content to optimize your cluster.

What kubeye can do

• Kubeye can find problems of your cluster control plane, including kube-apiserver/kube-controller-manager/etcd, etc.
• Kubeye helps you detect all kinds of node problems, including memory/cpu/disk pressure, unexpected kernel error logs, etc.
• Kubeye validates your workloads yaml specs against industry best practice, helps you make your cluster stable.

Checklist

YES/NO	CHECK ITEM	Description
✅	ETCDHealthStatus	if etcd is up and running normally
✅	ControllerManagerHealthStatus	if kubernetes kube-controller-manager is up and running normally.
✅	SchedulerHealthStatus	if kubernetes kube-scheduler
✅	NodeMemory	if node memory usage is above threshold
✅	DockerHealthStatus	if docker is up and running
✅	NodeDisk	if node disk usage is above given threshold
✅	KubeletHealthStatus	if kubelet is active and running normally
✅	NodeCPU	if node cpu usage is above the given threshold
✅	NodeCorruptOverlay2	Overlay2 is not available
✅	NodeKernelNULLPointer	the node displays NotReady
✅	NodeDeadlock	A deadlock is a phenomenon in which two or more processes are waiting for each other as they compete for resources
✅	NodeOOM	Monitor processes that consume too much memory, especially those that consume a lot of memory very quickly, and the kernel kill them to prevent them from running out of memory
✅	NodeExt4Error	Ext4 mount error
✅	NodeTaskHung	Check to see if there is a process in state D for more than 120s
✅	NodeUnregisterNetDevice	Check corresponding net
✅	NodeCorruptDockerImage	Check docker image
✅	NodeAUFSUmountHung	Check storage
✅	NodeDockerHung	Docker hung, you can check docker log
✅	PodSetLivenessProbe	if livenessProbe set for every container in a pod
✅	PodSetTagNotSpecified	The mirror address does not declare tag or tag is latest
✅	PodSetRunAsPrivileged	Running a pod in a privileged mode means that the pod can access the host’s resources and kernel capabilities
✅	PodSetImagePullBackOff	Pod can't pull the image properly, so it can be pulled manually on the corresponding node
✅	PodSetImageRegistry	Checks if the image form is at the beginning of the corresponding harbor
✅	PodSetCpuLimitsMissing	No CPU Resource limit was declared
✅	PodNoSuchFileOrDirectory	Go into the container to see if the corresponding file exists
✅	PodIOError	This is usually due to file IO performance bottlenecks
✅	PodNoSuchDeviceOrAddress	Check corresponding net
✅	PodInvalidArgument	Check the storage
✅	PodDeviceOrResourceBusy	Check corresponding dirctory and PID
✅	PodFileExists	Check for existing files
✅	PodTooManyOpenFiles	The number of file /socket connections opened by the program exceeds the system set value
✅	PodNoSpaceLeftOnDevice	Check for disk and inode usage
✅	NodeApiServerExpiredPeriod	ApiServer certificate expiration date less than 30 days will be checked
✅	PodSetCpuRequestsMissing	The CPU Resource Request value was not declared
✅	PodSetHostIPCSet	Set the hostIP
✅	PodSetHostNetworkSet	Set the hostNetwork
✅	PodHostPIDSet	Set the hostPID
✅	PodMemoryRequestsMiss	No memory Resource Request value is declared
✅	PodSetHostPort	Set the hostPort
✅	PodSetMemoryLimitsMissing	No memory Resource limit value is declared
✅	PodNotReadOnlyRootFiles	The file system is not set to read-only
✅	PodSetPullPolicyNotAlways	The mirror pull strategy is not always
✅	PodSetRunAsRootAllowed	Executed as a root account
✅	PodDangerousCapabilities	You have the dangerous option in capabilities such as ALL/SYS_ADMIN/NET_ADMIN
✅	PodlivenessProbeMissing	ReadinessProbe was not declared
✅	privilegeEscalationAllowed	Privilege escalation is allowed
	NodeNotReadyAndUseOfClosedNetworkConnection	http2-max-streams-per-connection
	NodeNotReady	Failed to start ContainerManager Cannot set property TasksAccounting, or unknown property

unmarked items are under heavy development

Add your own check rules

Add custom npd rule

• Install NPD with ke install npd
• Edit configmap kube-system/node-problem-detector-config with kubectl,

 kubectl edit cm -n kube-system node-problem-detector-config

• Add exception log information under the rule of configMap, rules follow regular expressions.

Fault with your own custom best practice rules

• Prepare a rule yaml, for example, the following rule will validate your pod spec to make sure image are only from authorized registries.

checks:
  imageFromUnauthorizedRegistry: warning

customChecks:
  imageFromUnauthorizedRegistry:
    promptMessage: When the corresponding rule does not match. Show that image from an unauthorized registry.
    category: Images
    target: Container
    schema:
      '$schema': http://json-schema.org/draft-07/schema
      type: object
      properties:
        image:
          type: string
          not:
            pattern: ^quay.io

• Save the above rule as a yaml, for example, rule.yaml.
• Run kubeye with rule.yaml

root:# ke diags -f rule.yaml --kubeconfig ~/.kube/config
NAMESPACE     SEVERITY    NAME                      KIND         TIME                        MESSAGE
default       Warning     nginx                     Deployment   2020-11-27T17:18:31+08:00   [imageFromUnauthorizedRegistry]
kube-system   Warning     node-problem-detector     DaemonSet    2020-11-27T17:18:31+08:00   [livenessProbeMissing runAsPrivileged]
kube-system   Warning     calico-node               DaemonSet    2020-11-27T17:18:31+08:00   [cpuLimitsMissing runAsPrivileged]
kube-system   Warning     calico-kube-controllers   Deployment   2020-11-27T17:18:31+08:00   [cpuLimitsMissing livenessProbeMissing]
kube-system   Warning     nodelocaldns              DaemonSet    2020-11-27T17:18:31+08:00   [runAsPrivileged cpuLimitsMissing]
default       Warning     nginx                     Deployment   2020-11-27T17:18:31+08:00   [livenessProbeMissing cpuLimitsMissing]
kube-system   Warning     coredns                   Deployment   2020-11-27T17:18:31+08:00   [cpuLimitsMissing]