pods core, k8s, all the operations are around the pod, pod can be considered to bundle multiple containers. pod in the container cpu shared network storage.
, Pod can set the environment variable, before you can start a container, such as the implementation of post-closure hook (functions, commands),
, pod can check the health of the vessel, where a node can have more than the same POD
Labels are many key- value, the object may be named with a key, it is easier to find, identify the object. Variables can also be done from the command line
such as: Environment in ( Production's , qa ); ! Partitio; LabelSelector = Environment + in +% 28production % 2Cqa % 29 % 2Ctier + in +% 28frontend %29
kubectl get pods -l environment=production,tier=frontend 等
namespace is a set of resources and the combination of objects / container / frame, pods, service, etc. (except node and persisitendVolumes) belongs to a default namespace has:. default kube-system and
two resource groups ( kubectlGETNamespaces )
Replication Controller is used to ensure a fixed number of runs pod container. Somewhat similar to the process manager, but it manages the entire k8s in all of the node where all the pod
R / C work: 1. Create a pod 2. Rescheduling / Scaling / Rolling updates based on pod template: re-planning / zoom / Dynamic Update
Node is really host, at least each node to run docker / rkt, kubelete, kube- proxy Node Controller is responsible for: maintaining a node state, and Cloud Provider 2. synchronization Node
3. Node to a dispensing container with CIDR 4. remove NoExecute taint Pods on the Node
Node contains several information: 1) address: comprises a hostname, IP network and the external network IP
2) condition (for condition condition): comprising OutOfDisk, Ready, MemoryPressure and DiskPressure
. 3) capacity (capacity): on the Node available resources, including CPU, memory, and the total number of Pod
4) basic information (Info): comprises a kernel version, the container engine version, the OS type of
node may be arranged unschedulable: kubectl Cordon $ The NODENAME
ReplicaSet the next generation of RC
Service services, the same pod unified Foreign Service, Services by kube-proxy function
discovery service: the environment variable / DNS