はじめに
k8sの基本コマンドのまとめです。調べ直すの面倒なのでまとめました。ご活用ください！
ポッド、レプリカセットの基本情報を見たい時
（数の確認、動作中のもの etc.）
ターミナル
kubectl get pods
kubectl get rs
※ レスポンス例
NAME DESIRED CURRENT READY AGE
new-replica-set 4 4 0 56s
ポッド、レプリカセットの詳細情報を見たい時
（作成に使用しているイメージの確認、ポッドが動いていない原因を知りたい時 etc.）
ターミナル
kubectl describe pods
※ レスポンス例（ポッド）
ace: default
Priority: 0
Service Account: default
Node: controlplane/172.25.0.33
Start Time: Tue, 28 Mar 2023 11:11:44 +0000
Labels: name=busybox-pod
Annotations: <none>
Status: Pending
IP: 10.42.0.9
IPs:
IP: 10.42.0.9
Controlled By: ReplicaSet/new-replica-set
Containers:
busybox-container:
Container ID:
Image: busybox777
Image ID:
Port: <none>
Host Port: <none>
Command:
sh
-c
echo Hello Kubernetes! && sleep 3600
State: Waiting
Reason: ImagePullBackOff
Ready: False
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-w6crj (ro)
Conditions:
Type Status
Initialized True
Ready False
ContainersReady False
PodScheduled True
Volumes:
kube-api-access-w6crj:
Type: Projected (a volume that contains injected data from multiple sources)
TokenExpirationSeconds: 3607
ConfigMapName: kube-root-ca.crt
ConfigMapOptional: <nil>
DownwardAPI: true
QoS Class: BestEffort
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 15m default-scheduler Successfully assigned default/new-replica-set-bv9br to controlplane
Normal Pulling 14m (x4 over 15m) kubelet Pulling image "busybox777"
Warning Failed 14m (x4 over 15m) kubelet Failed to pull image "busybox777": rpc error: code = Unknown desc = failed to pull and unpack image "docker.io/library/busybox777:latest": failed to resolve reference "docker.io/library/busybox777:latest": pull access denied, repository does not exist or may require authorization: server message: insufficient_scope: authorization failed
Warning Failed 14m (x4 over 15m) kubelet Error: ErrImagePull
Warning Failed 14m (x6 over 15m) kubelet Error: ImagePullBackOff
Normal BackOff 43s (x64 over 15m) kubelet Back-off pulling image "busybox777"
Name: new-replica-set-hz4d2
Namespace: default
Priority: 0
Service Account: default
Node: controlplane/172.25.0.33
Start Time: Tue, 28 Mar 2023 11:11:44 +0000
Labels: name=busybox-pod
Annotations: <none>
Status: Pending
IP: 10.42.0.11
IPs:
IP: 10.42.0.11
Controlled By: ReplicaSet/new-replica-set
Containers:
busybox-container:
Container ID:
Image: busybox777
Image ID:
Port: <none>
Host Port: <none>
Command:
sh
-c
echo Hello Kubernetes! && sleep 3600
State: Waiting
Reason: ImagePullBackOff
Ready: False
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-ntpmm (ro)
Conditions:
Type Status
Initialized True
Ready False
ContainersReady False
PodScheduled True
Volumes:
kube-api-access-ntpmm:
Type: Projected (a volume that contains injected data from multiple sources)
TokenExpirationSeconds: 3607
ConfigMapName: kube-root-ca.crt
ConfigMapOptional: <nil>
DownwardAPI: true
QoS Class: BestEffort
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 15m default-scheduler Successfully assigned default/new-replica-set-hz4d2 to controlplane
Normal Pulling 14m (x4 over 15m) kubelet Pulling image "busybox777"
Warning Failed 14m (x4 over 15m) kubelet Failed to pull image "busybox777": rpc error: code = Unknown desc = failed to pull and unpack image "docker.io/library/busybox777:latest": failed to resolve reference "docker.io/library/busybox777:latest": pull access denied, repository does not exist or may require authorization: server message: insufficient_scope: authorization failed
Warning Failed 14m (x4 over 15m) kubelet Error: ErrImagePull
Warning Failed 14m (x6 over 15m) kubelet Error: ImagePullBackOff
Normal BackOff 43s (x65 over 15m) kubelet Back-off pulling image "busybox777"
Name: new-replica-set-h9ms4
Namespace: default
Priority: 0
Service Account: default
Node: controlplane/172.25.0.33
Start Time: Tue, 28 Mar 2023 11:11:44 +0000
Labels: name=busybox-pod
Annotations: <none>
Status: Pending
IP: 10.42.0.12
IPs:
IP: 10.42.0.12
Controlled By: ReplicaSet/new-replica-set
Containers:
busybox-container:
Container ID:
Image: busybox777
Image ID:
Port: <none>
Host Port: <none>
Command:
sh
-c
echo Hello Kubernetes! && sleep 3600
State: Waiting
Reason: ImagePullBackOff
Ready: False
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-rw67h (ro)
Conditions:
Type Status
Initialized True
Ready False
ContainersReady False
PodScheduled True
Volumes:
kube-api-access-rw67h:
Type: Projected (a volume that contains injected data from multiple sources)
TokenExpirationSeconds: 3607
ConfigMapName: kube-root-ca.crt
ConfigMapOptional: <nil>
DownwardAPI: true
QoS Class: BestEffort
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 15m default-scheduler Successfully assigned default/new-replica-set-h9ms4 to controlplane
Normal Pulling 14m (x4 over 15m) kubelet Pulling image "busybox777"
Warning Failed 14m (x4 over 15m) kubelet Failed to pull image "busybox777": rpc error: code = Unknown desc = failed to pull and unpack image "docker.io/library/busybox777:latest": failed to resolve reference "docker.io/library/busybox777:latest": pull access denied, repository does not exist or may require authorization: server message: insufficient_scope: authorization failed
Warning Failed 14m (x4 over 15m) kubelet Error: ErrImagePull
Warning Failed 13m (x6 over 15m) kubelet Error: ImagePullBackOff
Normal BackOff 40s (x64 over 15m) kubelet Back-off pulling image "busybox777"
Name: new-replica-set-4w8ln
Namespace: default
Priority: 0
Service Account: default
Node: controlplane/172.25.0.33
Start Time: Tue, 28 Mar 2023 11:11:44 +0000
Labels: name=busybox-pod
Annotations: <none>
Status: Pending
IP: 10.42.0.10
IPs:
IP: 10.42.0.10
Controlled By: ReplicaSet/new-replica-set
Containers:
busybox-container:
Container ID:
Image: busybox777
Image ID:
Port: <none>
Host Port: <none>
Command:
sh
-c
echo Hello Kubernetes! && sleep 3600
State: Waiting
Reason: ImagePullBackOff
Ready: False
Restart Count: 0
Environment: <none>
Mounts:
/var/run/secrets/kubernetes.io/serviceaccount from kube-api-access-kl5tb (ro)
Conditions:
Type Status
Initialized True
Ready False
ContainersReady False
PodScheduled True
Volumes:
kube-api-access-kl5tb:
Type: Projected (a volume that contains injected data from multiple sources)
TokenExpirationSeconds: 3607
ConfigMapName: kube-root-ca.crt
ConfigMapOptional: <nil>
DownwardAPI: true
QoS Class: BestEffort
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 15m default-scheduler Successfully assigned default/new-replica-set-4w8ln to controlplane
Normal Pulling 14m (x4 over 15m) kubelet Pulling image "busybox777"
Warning Failed 14m (x4 over 15m) kubelet Failed to pull image "busybox777": rpc error: code = Unknown desc = failed to pull and unpack image "docker.io/library/busybox777:latest": failed to resolve reference "docker.io/library/busybox777:latest": pull access denied, repository does not exist or may require authorization: server message: insufficient_scope: authorization failed
Warning Failed 14m (x4 over 15m) kubelet Error: ErrImagePull
Warning Failed 13m (x6 over 15m) kubelet Error: ImagePullBackOff
Normal BackOff 43s (x64 over 15m) kubelet Back-off pulling image "busybox777"
ターミナル
kubectl describe rs
※ レスポンス例（レプリカセット）
Name: new-replica-set
Namespace: default
Selector: name=busybox-pod
Labels: <none>
Annotations: <none>
Replicas: 4 current / 4 desired
Pods Status: 0 Running / 4 Waiting / 0 Succeeded / 0 Failed
Pod Template:
Labels: name=busybox-pod
Containers:
busybox-container:
Image: busybox777
Port: <none>
Host Port: <none>
Command:
sh
-c
echo Hello Kubernetes! && sleep 3600
Environment: <none>
Mounts: <none>
Volumes: <none>
Events:
Type Reason Age From Message
---- ------ ---- ---- -------
Normal SuccessfulCreate 6m43s replicaset-controller Created pod: new-replica-set-bv9br
Normal SuccessfulCreate 6m43s replicaset-controller Created pod: new-replica-set-4w8ln
Normal SuccessfulCreate 6m43s replicaset-controller Created pod: new-replica-set-hz4d2
Normal SuccessfulCreate 6m43s replicaset-controller Created pod: new-replica-set-h9ms4
ポッドを削除したい時
ターミナル
kubectl delete pod <pod-name>
参考
こちらのUdemyの講義で詳しく解説があります。
初心者でも分かりやすく、実行環境を提供してくれているので、環境構築の手間なく進められます。
興味のある方はぜひ受講してみてください！
Kubernetes for the Absolute Beginners - Hands-on