When you follow instructions from Basic usage or Advanced usage, Docker will automatically create named volumes for every --volume
/ -v
argument passed. Named volume will make it easy for you to mount the same persisted data even if you delete then re-create the container:
$ docker run -d \
--name nginx-proxy \
-p 80:80 \
-p 443:443 \
-v certs:/etc/nginx/certs \
-v vhost:/etc/nginx/vhost.d \
-v html:/usr/share/nginx/html \
-v /var/run/docker.sock:/tmp/docker.sock:ro \
nginxproxy/nginx-proxy
$ docker volume ls
DRIVER VOLUME NAME
local certs
local vhost
local html
If you don't prefix your volumes with a name, Docker will instead create anonymous volumes (volumes with a random name). Those volume persist after the container is deleted but aren't automatically re-mounted when you re-create the container. Their usage is not recommended as they don't provide any advantages over named volumes and make keeping tracks of what volume store which data way harder.
$ docker run -d \
--name nginx-proxy \
-p 80:80 \
-p 443:443 \
-v /etc/nginx/certs \
-v /etc/nginx/vhost.d \
-v /usr/share/nginx/html \
-v /var/run/docker.sock:/tmp/docker.sock:ro \
nginxproxy/nginx-proxy
$ docker volume ls
DRIVER VOLUME NAME
local 287be3abd610e5566500d719ceb8b952952f12c9324ef02d05785d4ee9737ae9
local 6530b1b40cf89efb71aa7fd19bddec927fa2bcae59b04b9c1c850af72ffe0123
local f260f71fefadcdfc311d285d69151f2312915174d3fb1fab89949ec5ec871a54
Alternatively, you might want to store the certificates on a local folder rather than letting Docker create and manage a volume for them. This is easily achieved by using a host volume (binding an absolute path on your host to the /ect/nginx/certs
folder on your containers):
-v /path/to/certificates:/etc/nginx/certs
No matter the type of volume you choose, if you set them on the nginx-proxy or nginx container and use --volumes_from
on the others containers, they will automatically be mounted inside the container to the path your first defined.
If you want to restrain the nginx and docker-gen processes to read only access on the certificates, you'll have to use different volume flags depending on the container.
Example with named volumes:
-v certs:/etc/nginx/certs:ro
on the nginx-proxy or nginx + docker-gen container(s).
-v certs:/etc/nginx/certs:rw
on the acme-companion container.
By default, the acme-companion container will enforce the following ownership and permissions scheme on the files it creates and manage:
[drwxr-xr-x] /etc/nginx/certs
├── [-rw-r--r-- root root] dhparam.pem
├── [-rw-r--r-- root root] default.crt
├── [-rw------- root root] default.key
├── [drwxr-xr-x root root] domain.tld
│ ├── [-rw-r--r-- root root] cert.pem
│ ├── [-rw-r--r-- root root] chain.pem
│ ├── [-rw-r--r-- root root] fullchain.pem
│ └── [-rw------- root root] key.pem
├── [lrwxrwxrwx root root] domain.tld.chain.pem -> ./domain.tld/chain.pem
├── [lrwxrwxrwx root root] domain.tld.crt -> ./domain.tld/fullchain.pem
├── [lrwxrwxrwx root root] domain.tld.dhparam.pem -> ./dhparam.pem
└── [lrwxrwxrwx root root] domain.tld.key -> ./domain.tld/key.pem
This behavior can be customized using the following environment variable on the acme-companion container:
FILES_UID
- Set the user owning the files and folders managed by the container. The variable can be either a user name if this user exists inside the container or a user numeric ID. Default toroot
(user ID0
).FILES_GID
- Set the group owning the files and folders managed by the container. The variable can be either a group name if this group exists inside the container or a group numeric ID. Default to the same value asFILES_UID
.FILES_PERMS
- Set the permissions of the private keys. The variable must be a valid octal permission setting and defaults to600
.FOLDERS_PERMS
- Set the permissions of the folders managed by the container. The variable must be a valid octal permission setting and defaults to755
.
For example, FILES_UID=1000
, FILES_PERMS=644
and FOLDERS_PERMS=700
will result in the following:
[drwxr-xr-x] /etc/nginx/certs
├── [-rw-r--r-- 1000 1000] dhparam.pem
├── [-rw-r--r-- 1000 1000] default.crt
├── [-rw-r--r-- 1000 1000] default.key
├── [drwx------ 1000 1000] domain.tld
│ ├── [-rw-r--r-- 1000 1000] cert.pem
│ ├── [-rw-r--r-- 1000 1000] chain.pem
│ ├── [-rw-r--r-- 1000 1000] fullchain.pem
│ └── [-rw-r--r-- 1000 1000] key.pem
├── [lrwxrwxrwx 1000 1000] domain.tld.chain.pem -> ./domain.tld/chain.pem
├── [lrwxrwxrwx 1000 1000] domain.tld.crt -> ./domain.tld/fullchain.pem
├── [lrwxrwxrwx 1000 1000] domain.tld.dhparam.pem -> ./dhparam.pem
└── [lrwxrwxrwx 1000 1000] domain.tld.key -> ./domain.tld/key.pem