# DaemonSet

<mark style="color:blue;">**DaemonSet（守护进程集，缩写为 ds）**</mark>和守护进程类似，它在符合匹配条件的节点上均部署一个 Pod。

这种用法适合有这种需求的应用：

* 在每个 Node 上都运行一个 GlusterFS 存储或者 Ceph 存储的 Daemon 进程。
* 在每个 Node 上都运行一个日志采集程序，例如 Fluentd 或者 Logstach。
* 在每个 Node 上都运行一个性能监控程序，采集该 Node 的运行性能数据，例如 Prometheus Node Exporter、collectd、New Relic agent 或者 Ganglia gmond 等。

DaemonSet 的 Pod 调度策略与 RC 类似，除了使用系统内置的算法在每个 Node 上进行调度，也可以在Pod 的定义中使用 NodeSelector 或 NodeAffinity 来指定满足条件的 Node 进行调度。


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://bohans.gitbook.io/devops/kubernetes/ji-chu-zhi-shi/kubernetes-diao-du/daemonset.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.