'Get node status with kubectl custom-columns [closed]

I'm experimenting with kubectl -o=custom-columns and I wonder if there is a way to get node status. I'm can get the nodename with this

k get nodes -o=custom-columns=NAME:.metadata.name

but is there a way to get the node status (ready, notready)?

kuberneteskubectl


Solution 1:[1]

Try to run kubectl get nodes as following:

kubectl get nodes -o custom-columns=STATUS:status.conditions[-1].type

Solution 2:[2]

Try to run kubectl get nodes as following:

kubectl get nodes -o custom-columns="STATUS:status.conditions[?(@.status=='True')].type"

Solution 3:[3]

It is not so easy, beacuse it depends of amount of infgoramtin about your worker, for example:

        "conditions": [
            {
                "lastHeartbeatTime": "2019-07-26T13:04:26Z",
                "lastTransitionTime": "2019-07-26T13:04:26Z",
                "message": "Weave pod has set this",
                "reason": "WeaveIsUp",
                "status": "False",
                "type": "NetworkUnavailable"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:21:02Z",
                "lastTransitionTime": "2019-06-29T14:23:33Z",
                "message": "kubelet has sufficient memory available",
                "reason": "KubeletHasSufficientMemory",
                "status": "False",
                "type": "MemoryPressure"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:21:02Z",
                "lastTransitionTime": "2019-06-29T14:23:33Z",
                "message": "kubelet has no disk pressure",
                "reason": "KubeletHasNoDiskPressure",
                "status": "False",
                "type": "DiskPressure"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:21:02Z",
                "lastTransitionTime": "2019-06-29T14:23:33Z",
                "message": "kubelet has sufficient PID available",
                "reason": "KubeletHasSufficientPID",
                "status": "False",
                "type": "PIDPressure"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:21:02Z",
                "lastTransitionTime": "2019-07-25T17:06:09Z",
                "message": "kubelet is posting ready status. AppArmor enabled",
                "reason": "KubeletReady",
                "status": "True",
                "type": "Ready"
            }
        ],

for bare metal cluster so in this case your command will be:

kubectl get no -ocustom-columns=Name:metadata.name,Status:status.conditions[4].type

but for gke node

        "conditions": [
            {
                "lastHeartbeatTime": "2019-08-09T11:26:19Z",
                "lastTransitionTime": "2019-07-31T14:09:41Z",
                "message": "docker overlay2 is functioning properly",
                "reason": "CorruptDockerOverlay2",
                "status": "False",
                "type": "CorruptDockerOverlay2"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:26:19Z",
                "lastTransitionTime": "2019-07-31T14:04:39Z",
                "message": "kernel has no deadlock",
                "reason": "KernelHasNoDeadlock",
                "status": "False",
                "type": "KernelDeadlock"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:26:19Z",
                "lastTransitionTime": "2019-07-31T14:04:39Z",
                "message": "Filesystem is not read-only",
                "reason": "FilesystemIsNotReadOnly",
                "status": "False",
                "type": "ReadonlyFilesystem"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:26:19Z",
                "lastTransitionTime": "2019-07-31T14:09:41Z",
                "message": "node is functioning properly",
                "reason": "UnregisterNetDevice",
                "status": "False",
                "type": "FrequentUnregisterNetDevice"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:26:19Z",
                "lastTransitionTime": "2019-07-31T14:09:41Z",
                "message": "kubelet is functioning properly",
                "reason": "FrequentKubeletRestart",
                "status": "False",
                "type": "FrequentKubeletRestart"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:26:19Z",
                "lastTransitionTime": "2019-07-31T14:09:42Z",
                "message": "docker is functioning properly",
                "reason": "FrequentDockerRestart",
                "status": "False",
                "type": "FrequentDockerRestart"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:26:19Z",
                "lastTransitionTime": "2019-07-31T14:09:43Z",
                "message": "containerd is functioning properly",
                "reason": "FrequentContainerdRestart",
                "status": "False",
                "type": "FrequentContainerdRestart"
            },
            {
                "lastHeartbeatTime": "2019-08-02T13:32:49Z",
                "lastTransitionTime": "2019-08-02T13:32:49Z",
                "message": "NodeController create implicit route",
                "reason": "RouteCreated",
                "status": "False",
                "type": "NetworkUnavailable"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:27:03Z",
                "lastTransitionTime": "2019-07-31T14:04:40Z",
                "message": "kubelet has sufficient memory available",
                "reason": "KubeletHasSufficientMemory",
                "status": "False",
                "type": "MemoryPressure"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:27:03Z",
                "lastTransitionTime": "2019-07-31T14:04:40Z",
                "message": "kubelet has no disk pressure",
                "reason": "KubeletHasNoDiskPressure",
                "status": "False",
                "type": "DiskPressure"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:27:03Z",
                "lastTransitionTime": "2019-07-31T14:04:40Z",
                "message": "kubelet has sufficient PID available",
                "reason": "KubeletHasSufficientPID",
                "status": "False",
                "type": "PIDPressure"
            },
            {
                "lastHeartbeatTime": "2019-08-09T11:27:03Z",
                "lastTransitionTime": "2019-07-31T14:04:41Z",
                "message": "kubelet is posting ready status. AppArmor enabled",
                "reason": "KubeletReady",
                "status": "True",
                "type": "Ready"
            }
        ],

so it will be 

kubectl get nodes  -o=custom-columns=NAME:.metadata.name,STATUS:.status.conditions[11].type

Solution 4:[4]

Try to execute:

$ kubectl get nodes  -o=custom-columns=NAME:.metadata.name,STATUS:.status.conditions[12].type

More information about custom-columns you can find here: custom-columns.

Useful article: custom-column-example.

Sources

This article follows the attribution requirements of Stack Overflow and is licensed under CC BY-SA 3.0.

Source: Stack Overflow

Solution Source
Solution 1 32cupo
Solution 2
Solution 3 FL3SH
Solution 4 Malgorzata

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