k8s 对比其它框架
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| mesos
Marathon
spark/hadoop
docker/LXC
|
cs 架构
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| +-------------+
| |
| | +---------------+
| | +-----> | Node 1 |
| Kubernetes | | +---------------+
+-----------------+ | Server | |
| CLI | | | | +---------------+
| (Kubectl) |----------->| ( Master ) |<------+-----> | Node 2 |
| | | | | +---------------+
+-----------------+ | | |
| | | +---------------+
| | +-----> | Node 3 |
| | +---------------+
+-------------+
|
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| +----------------------------------------------------------+
| Master |
| +-------------------------+ |
| +------->| API Server |<--------+ |
| | | | | |
| v +-------------------------+ v |
| +----------------+ ^ +--------------------+ |
| | | | | | |
| | Scheduler | | | Controller Manager | |
| | | | | | |
| +----------------+ v +--------------------+ |
| +------------------------------------------------------+ |
| | | |
| | Cluster state store | |
| | | |
| +------------------------------------------------------+ |
+----------------------------------------------------------+
|
scheduler 负责通过Api 调度 pod 到某个node， 调度程序只考虑开始Node的状态，而不考虑在调度过程中的状态，
最终 pod 能否运行在 node 上由 kubelet 裁定
k8s 实现 Container Runtime Interface
Container Runtime：
k8s 通过 kube-proxy 编排 iptables 实现流量转发
K8S 集群，会默认机器的基本信息，并计算在此 Node 上可调度的 Pod 数量
查看基本信息的命令:
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| cat /etc/issue
cat /etc/os-release
cat /proc/cpuinfo
cat /proc/meminfo
free
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kubelet --hostname-override <主机名> 可以修改主机名
