Commandes utiles pour K8S

Pour K8S, les commandes sont assez difficiles de base. De plus, il existe certaines commandes assez tricky que je vais essayer de répertorier ici

$ kubectl delete pods --field-selector=status.phase!=Running -A

Permet de supprimer les pods de la liste qui ne sont pas running (Dont les evicted)

$ kubectl get Issuers,ClusterIssuers,Certificates,CertificateRequests,Orders,Challenges -A
NAMESPACE   NAME                                            READY   AGE
teleport    issuer.cert-manager.io/letsencrypt-production   True    392d

NAMESPACE   NAME                                   READY   SECRET         AGE
teleport    certificate.cert-manager.io/teleport   True    teleport-tls   392d

NAMESPACE   NAME                                                APPROVED   DENIED   READY   ISSUER                   REQUESTOR                                         AGE
teleport    certificaterequest.cert-manager.io/teleport-467wl   True                True    letsencrypt-production   system:serviceaccount:cert-manager:cert-manager   213d
teleport    certificaterequest.cert-manager.io/teleport-7xs8t   True                True    letsencrypt-production   system:serviceaccount:cert-manager:cert-manager   33d
teleport    certificaterequest.cert-manager.io/teleport-bbw7j   True                True    letsencrypt-production   system:serviceaccount:cert-manager:cert-manager   272d
teleport    certificaterequest.cert-manager.io/teleport-jb2mk   True                True    letsencrypt-production   system:serviceaccount:cert-manager:cert-manager   153d
teleport    certificaterequest.cert-manager.io/teleport-kgxhx   True                True    letsencrypt-production   system:serviceaccount:cert-manager:cert-manager   332d
teleport    certificaterequest.cert-manager.io/teleport-splkd   True                True    letsencrypt-production   system:serviceaccount:cert-manager:cert-manager   93d

NAMESPACE   NAME                                                   STATE   AGE
teleport    order.acme.cert-manager.io/teleport-467wl-1964815354   valid   213d
teleport    order.acme.cert-manager.io/teleport-7xs8t-1964815354   valid   33d
teleport    order.acme.cert-manager.io/teleport-bbw7j-1964815354   valid   272d
teleport    order.acme.cert-manager.io/teleport-jb2mk-1964815354   valid   153d
teleport    order.acme.cert-manager.io/teleport-kgxhx-1964815354   valid   332d
teleport    order.acme.cert-manager.io/teleport-splkd-1964815354   valid   93d

Liste toutes les ressources qui sont link à la génération d'un certificat

$ kubectl get pods -o name | xargs -I{} kubectl exec {} -- <command goes here>

Permet d'exécuter la même commande sur de multiples pods

$ kubectl get pods --all-namespaces -o=json | jq -c '.items[] | {name: .metadata.name, namespace: .metadata.namespace, claimName: .spec |  select( has ("volumes") ).volumes[] | select( has ("persistentVolumeClaim") ).persistentVolumeClaim.claimName }'
{"name":"loki-backend-0","namespace":"dyn-tools","claimName":"data-loki-backend-0"}
{"name":"loki-write-0","namespace":"dyn-tools","claimName":"data-loki-write-0"}
{"name":"loki-write-1","namespace":"dyn-tools","claimName":"data-loki-write-1"}
{"name":"prometheus-alertmanager-0","namespace":"dyn-tools","claimName":"storage-prometheus-alertmanager-0"}
{"name":"prometheus-server-7774557469-6jrhk","namespace":"dyn-tools","claimName":"prometheus-server"}

Permet de lister les PVC qui sont actuellement asssociés à un pod

kubectl get secret postgresql-secrets -o go-template='{{ range $key, $value := .data }}{{ $key }}{{ ": " }}{{ $value | base64decode }}{{ "\n" }}{{ end }}'

Permet de lister tous les secrets et de les decoder