Docker - 解決建立 nginx 容器嘗試挂載 nginx.conf 檔案時報錯： mounting "/root/nginx.conf" to rootfs at "/etc/nginx/nginx.conf" caused: mount through procfd: not a directory:

背景

在自己的伺服器上想通過 nginx 鏡像建立容器，并挂載鏡像自帶的 nginx.conf 檔案

docker run -it -d -v ~/nginx.conf:/etc/nginx/nginx.conf nginx      

但是報錯了

[root@poloyy ~]# docker run -it -d -v ~/nginx.conf:/etc/nginx/nginx.conf nginx
e0e4b40446a64927603b85854c3a6472b2dfa5681fcbfa0e170c16b15e5c8fdd
docker: Error response from daemon: OCI runtime create failed: container_linux.go:380: starting container process caused: process_linux.go:545: container init caused: rootfs_linux.go:76: mounting "/root/nginx.conf" to rootfs at "/etc/nginx/nginx.conf" caused: mount through procfd: not a directory: unknown: Are you trying to mount a directory onto a file (or vice-versa)? Check if the specified host path exists and is the expected type.
[root@poloyy ~]# client_loop: send disconnect: Broken pipe      

提取關鍵錯誤資訊

mounting "/root/nginx.conf" to rootfs at "/etc/nginx/nginx.conf" caused: mount through procfd: not a directory: unknown: Are you trying to mount a directory onto a file (or vice-versa)?      

将“/root/nginx.conf”挂載到“/etc/nginx/nginx.conf”的rootfs導緻：通過procfd挂載：不是目錄：未知：您是否試圖将目錄挂載到檔案上（反之亦然） 

根因

• 不支援直接挂載檔案，隻能挂載檔案夾
• 想要挂載檔案，必須主控端也要有對應的同名檔案

解決方法

• 可以先不挂載 nginx.conf
• 先從容器中複制 nginx.conf 出來
• 然後可以自行修改 nginx.conf，自定義配置項
• 建立正式使用的 nginx 容器

從 test 容器中複制 nginx.conf 出來

當然也可以去網上随便找個 nginx.conf，最重要的是主控端要有個 nginx.conf

docker run --name test -d nginx  
docker cp test:/etc/nginx/nginx.conf /data/      

建立正式的 nginx 容器，挂載 nginx.conf 檔案

可以賦予權限

docker run --privileged -it -p 80:80 \
-v /data/nginx/conf/nginx.conf:/etc/nginx/nginx.conf:ro \
-v /data/nginx/conf/conf.d:/etc/nginx/conf.d:ro \
-v /data/nginx/html:/usr/share/nginx/html:rw \
-v /data/nginx/logs:/var/log/nginx -d nginx