Etcd is an open-source, distributed key-value database. In key-value databases, each record contains a key which is the unique identifier. A value is associated with the key. Etcd is a major component of many projects such as Kubernetes, Rook, CoreDNS, etc. Kubernetes uses etcd as a data store to maintain information about the state of the cluster. It stores the metadata ("data about data") in a fault-tolerant setup, using multiple servers. So even if one server fails, etcd should still work, if the other servers are still available.

ETCD in Kubernetes

• Nodes
• Pods
• Configs
• Secrets
• Accounts
• Roles
• Bindings
• Others

kubectl exec etcd-master -n kube-system etcdctl get / --prefix -keys-only

etcdctl endpoint health

etcdctl endpoint status

Save Snapshot

unset ETCDCTL_ENDPOINTS
etcdctl --endpoints=https://192.1.1.1:2379 snapshot save my.db

 etcdctl --write-out=table --endpoints=$ENDPOINTS snapshot status my.db