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+My notes from https://www.youtube.com/watch?v=s_o8dwzRlu4 and other videos
+
+# What is kubernetes
+* an open source container orchestration tool
+* helps you manage apps that are made of 100s or 1000s of containers in different dev environments (cloud, local, etc)
+
+
+## Container Orchestration Tool
+* manages many containers
+* offers high availability (little to no downtime)
+* offers scalability
+* offers disaster recovery (backup and restore)
+
+
+## Kubernetes Cluster Structure
+### at least 1 Master Node
+has:
+* API Server (the entrypoint for the kubernetes cluster), this is what the kubernetes clients (UI, API, CLI, etc) will talk to
+* Controller Manager
+	- keeps track of the cluster (i.e. a container has died, restart it)
+* Scheduler
+	- decides on which node any new container should be scheduled
+	- it does this based on workload, server resources on each node, etc
+* etcd
+	- key/value storage for the current state of the cluster
+	- holds the current config data, status data of each node/the node's container, etc
+	- snapshots of this etcd are used for RECOVERY
+
+**connected to it, there are many smaller**
+
+### Worker Nodes
+all of which have:
+* a kublet (kubernetes process that talks to other kublets and master node) running on it
+* docker containers (which do the work)
+
+
+### Virtual Network
+* spans all the nodes in the cluster
+* enables the nodes to talk to each other
+
+*Note: in most prod environments, it's recommended to have more than one master node so that if one of them fails, the process can continue running*