DevOps Cribs

crib.md

DevOps Crib

Networking

• https://staaldraad.github.io/2017/12/20/netstat-without-netstat/
• https://www.howtoforge.com/linux-lsof-command/
• https://www.tecmint.com/find-listening-ports-linux/
• https://tldp.org/LDP/nag2/x-087-2-iface.netstat.html

AWS

VPC

• https://aws.amazon.com/premiumsupport/knowledge-center/vpc-peering-connectivity/
• https://aws.amazon.com/blogs/aws/new-vpc-insights-analyzes-reachability-and-visibility-in-vpcs/

EKS

• ALB Ingress Annotations
• ALB Ingrss Docs

K8s

Creating Clusters

• https://kubernetes.io/docs/setup/production-environment/tools/kubeadm/create-cluster-kubeadm/

API

• API docs one-page

Debugging Control Plane / Worker issues

• Use ps aux | grep <service> to list currently applied options for kubelet/apiserver etc.
• Use systemctl status <service> for non-k8s-managed services

Resource Limits

• https://medium.com/@betz.mark/understanding-resource-limits-in-kubernetes-cpu-time-9eff74d3161b
• https://medium.com/@betz.mark/understanding-resource-limits-in-kubernetes-memory-6b41e9a955f9
• https://sysdig.com/blog/kubernetes-limits-requests/

Services

• https://medium.com/avmconsulting-blog/service-types-in-kubernetes-24a1587677d6
• https://www.tutorialspoint.com/kubernetes/kubernetes_service.htm

Taints & Toleration

• https://kubernetes.io/docs/concepts/scheduling-eviction/taint-and-toleration/
• https://medium.com/kubernetes-tutorials/making-sense-of-taints-and-tolerations-in-kubernetes-446e75010f4e
• https://github.com/infracloudio/kubernetes-scheduling-examples/blob/master/taints/README.md
• https://kubernetes.io/docs/reference/labels-annotations-taints/

Node Affinity

• https://kubernetes.io/docs/tasks/configure-pod-container/assign-pods-nodes-using-node-affinity/

Networking

• https://kubernetes.io/docs/concepts/cluster-administration/networking/

Secrets

• https://kubernetes.io/docs/tasks/administer-cluster/encrypt-data/

TLS

• https://kubernetes.io/docs/reference/command-line-tools-reference/kubelet-tls-bootstrapping/

kubectl snips

• https://kubernetes.io/docs/reference/kubectl/cheatsheet/
• https://kubernetes.io/docs/reference/generated/kubectl/kubectl-commands

Run an interactive busybox debug pod

kubectl run -i --tty --rm debug --image=busybox --restart=Never -- sh

Run mysql test

kubectl run -i --tty --rm debug --image=mysql --restart=Never -- mysql -h mysql -proot123 registry -e 'show tables;'