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archive/docs/docker&k8s/entrypoint和cmd.md

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+entrypoint是容器执行的命令cmd是执行的命令或者参数.
+
+```bash
+docker run --entrypoint /bin/bash test bash
+#          覆盖ENTRYPOINT  覆盖CMD
+```
+
+```dockerfile
+ENTRYPOINT ["/bin/echo", "hello"]
+CMD ["world"]
+```
+
+![image-20210114105711640](entrypoint.assets/image-20210114105711640.png)
+
+像这样执行结果是:`Hello world`
+
+覆盖CMD的参数
+
+```bash
+docker run test eicas
+```
+
+![image-20210114111521900](entrypoint.assets/image-20210114111521900.png)
+
+感觉就像是将两个命令拼接起来
+
+### 在k8s中的对应
+
+[k8s文档地址](https://kubernetes.io/zh/docs/tasks/inject-data-application/define-command-argument-container/#notes)
+
+![image-20210114112244500](entrypoint.assets/image-20210114112244500.png)
+
+
+
+### CMD和ENTRYPOINT执行的两种形式
+
+```dockerfile
+CMD "命令/参数"
+# 以shell执行,相当于会自动补全"/bin/sh -c ",等价于CMD ["/bin/sh -c ","\"命令/参数\""],ENTRYPOINT也是如此
+```
+
+![image-20210114112052386](entrypoint.assets/image-20210114112052386.png)
+
+![image-20210114105605169](https://i.loli.net/2021/01/14/6LMPTFvfbrkXjd1.png)
+
+![image-20210114111116997](entrypoint.assets/image-20210114111116997.png)
+
+ENTRYPOINT的shell方式下,无法接受参数
+
+![image-20210114111300414](entrypoint.assets/image-20210114111300414.png)
+
+```dockerfile
+CMD ["命令/参数","命令/参数"]
+# 以exec形式执行
+```
+
+![image-20210114105711640](entrypoint.assets/image-20210114105711640.png)
+