Term
|
Definition
| - kubectl top node (or pod) |
|
|
Term
|
Definition
- if single container
kubectl logs -f "pod"
- if multi containers
kubectl logs -f "pod" "container" |
|
|
Term
|
Definition
- kubectl rollout status deploy "name"
- kubectl rollout history deploy "name" |
|
|
Term
|
Definition
- recreate all (at same time)
- rolling update (one at a time - default) |
|
|
Term
| Set new deploy image (imperative) |
|
Definition
| kubectl set image deploy "name" old_image=new_image |
|
|
Term
| Undo rollout (or rollback) |
|
Definition
- kubectl rollout undo deploy "name"
- uses saved replica set |
|
|
Term
|
Definition
- kubectl create configmap "map name" --from-literal=key=value
- kubectl create configmap "map name" --from-file=filename |
|
|
Term
|
Definition
apiVersion: v1
kind: ConfigMap
metadata:
name: "map name"
data:
key1:value1 |
|
|
Term
|
Definition
| kubectl get/describe configmap (or cm) |
|
|
Term
|
Definition
spec:
envFrom:
- configMapRef:
name:
OR
containers:
- name:
image:
command:
env:
- name: key1
valueFrom:
configMapKeyRef:
name: special-config
key: key1 |
|
|
Term
|
Definition
- kubectl create secret generic \
"sec name" --from-literal=key1=value1
kubectl create secret generic \
"sec name" --from-file="filename" |
|
|
Term
|
Definition
apiVersion: v1
kind: Secret
metadata:
name: "name"
data:
key1: "base64-encoded-value" |
|
|
Term
|
Definition
- kubectl get secret "name" -o yaml
- values in base64 |
|
|
Term
|
Definition
spec:
containers:
- name:
envFrom:
- secretRef:
key1: value1
OR
spec:
envFrom
- secretRef
name: "sec-name"
OR
volumes:
- name:
secret:
secretName: "sec-name" |
|
|
Term
|
Definition
| kubectl exec -it "pod" cmd param |
|
|
Term
|
Definition
spec:
containers:
initContainers:
- name:
image:
command: ['cmd', 'param1', 'param2']
- name:
image:
command:
- if multi initContainers, each one run one at a time sequentially with each one finishing before next starts
- after all initContainers run, then run regular containers |
|
|
Term
|
Definition
- kubectl drain "node"
- "node" marked as unscheduable
- to reverse
-kubectl uncordon "node"
- kubectl cordon "node"
- don't schedule any pods on nodes
- pods recreated on other running nodes |
|
|
Term
|
Definition
- kubectl get nodes
- v(maj).(min).(patch)
- minor = features/functions
- patch = patches/bug fixes |
|
|
Term
|
Definition
- kube-apiserver can be X
- controller-manager & kube-schedeler can be X or X-1
- kubelet & kube-proxy can be X, X-1 or X-2
- kubectl can be X or X+1 > X-1
- only current minor plus last 2 minor vers supported |
|
|
Term
|
Definition
- upgrade only one minor version at a time
- upgrade master first
- cannot deploy, modify or access pods while upgrading master
- Strategy 1 - upgrade all nodes at once
- Strategy 2 - upgrade one node at a time
- Strategy 3 - add new node with latest ver to replace each node |
|
|
Term
|
Definition
- kubeadm upgrade plan
- get ver #'s and other data
- Upgrade steps:
1) update kubeadm (apt-get)
2) kubeadm upgrade apply "v#"
3) upgrade kubelet (apt-get)
4) systemctl restart kubelet
5) kubectl uncordon master
6) for each node one at a time
1) Move workloads with kubectl drain "node"
2) upgrade kubeadm & kubelet
3) kubeadm upgrade node
4) system restart kubelet
5) kubectl uncordon "node" |
|
|
Term
| to query/save all yaml configs |
|
Definition
| - kubectl get all -all-namespaces -o yaml > all-deploy-srvs.yaml |
|
|
Term
| to query/save/restore all etcd |
|
Definition
- etcdctl snapshot save snapshot.db
- etcdctl snapshot status snapshot.db
- etcdctl snapshot restore snapshot.db |
|
|
Term
|
Definition
- create snapshot
- service kube-apiserver stop
- restore snapshot using new token and data dir (if we want to dup a live cluster)
- change token and data dir in etcd.yaml
- systemctl daemon-reload
- service etcd restart
- service kube-apiserver start |
|
|
Term
|
Definition
- Resource configurations (yaml)
- ETCD DB |
|
|
