How to map config and sql which is located inside a volume?

[chkrause]

I want to use a volume which contains my config and the sql database:

docker volume create
--driver local
--opt type=nfs
--opt device=192.168.2.30:/volume1/docker/evcc
--opt o=addr=192.168.2.30,rsize=8192,wsize=8192,tcp,timeo=14,vers=4
--name evcc

I want to map the volume and configure some variables to be able to point to the correct values.
I tried several approaches but none of them is working. Any suggestions?

[coderph0x]

It's suggested to mount /etc/evcc.yml and /root/.evcc. If you want to have both inside the same named volume, you probably have to mess around with a symlink or so.

See also: https://docs.evcc.io/en/docs/installation/docker/

[chkrause]

I read this, but with using a volume it seems that it is not possible to mount a single file from a volume to a file inside the container.
This is what I already tried out:
docker run
-it
--name=evcc
--net macvlan0
--ip 192.168.2.241
-p 7070:7070
-p 8887:8887
-p 7090:7090/udp
-p 9522:9522/udp
-v /evcc/evcc.yaml:/etc/evcc.yaml
-d evcc/evcc:latest

And map the complete volume isn't also allowed based on the documentation.

[coderph0x]

Well, one volume is one volume, you can't mount it twice (iirc).

If you want to use only a single NFS share, then it's probably best to mount the share on the docker host, put the dot-directory and the yaml file there and mount them into the container like in the docs.

[GrimmiMeloni]

Agree with @coderph0x.
As an additional hint, please excuse if I am preaching to the choir - keep in mind, that volume mounts are inode based. (Not sure about NFS based one's, tough). In effect this can lead to aliasing effects, where you change the config on the host, but the container never sees those changes (because it is still holding the inode of the old version of the config). Recreation of the container is then required, a plain "restart" will not help. It's a nice pitfall, especially if you are fiddling with evcc's config to try things out.

[chkrause]

I did it as proposed:
I configured the NAS directly in my host system via fstab configuration to be able to use the following config:

docker run \
    -it \
    --name=evcc \
    --net macvlan0 \
    --ip 192.168.2.241 \
    -p 7070:7070 \
    -p 8887:8887 \
    -p 7090:7090/udp \
    -p 9522:9522/udp \
    -v /NAS/docker/evcc/evcc.yaml:/etc/evcc.yaml \
    -v /NAS/docker/evcc/.evcc:/root/.evcc \
    -d evcc/evcc:latest

Changing the config requires a restart of the docker container, but this works like a charm.