How to organize docker volumes into subdirectories using compose
Hei there. I've read that it's best practice to use docker volumes to store persistent container data (such as config, files) instead of using bindmount. So far, I've only used the latter and would like to change this.
From what I've read, all volumes are stored in var/lib/docker/volumes. I also understood, that a volume is basically a subdirectory in that path.
I'd like to keep things organized and would like the volumes of my containers to be stored in subdirectories for each stack in docker compose, e.g.
volumes/arr/qbit /arr/gluetun /nextcloud/nextcloud /nextcloud/database
Is this possible using compose?
Another noob question: is there any disadvantage to using the default network docker creates for each stack/container?
Just do bind mounts unless you really need docker volumes for something
Will do, thanks!
Never heard that bindmounts are bad practice. Never had problems with it. What did you read?
If it ain't broken ...
Yeah, that seems to be the gist of it. I've seen several people say that they prefer volumes as they are managed by docker and therefore easier to migrate / backup. Since I plan on moving to different hardware in the near future, I figured why not.
Also something about permissions, though I never had any problems with it. So as you said, I'm sticking with bind mounts for now.
Also I don't have a clue what I'm doing at least 50 percent of the time and just follow guides. That's why I wanted some clarification on that :)
Do not access volumes directly on filesystem. path may change. If you need access data on a volume just spawn temporary container an mount that volume.
If you have data else where on your server, you can use the options to volume to direct the mount there
driver: local driver_opts: type: none o: bind device: '/your/current/data'
Also reading the compose spec will help
Thanks, this looks like it'll do the job. I have not a lot of knowledge, so the specs are often a bit technical for me. I'll give it a go, thanks!
that is using bin mounts again. and i don't get why this is discouraged, i actualy do like to know where my data is stored and don't want to spin up a container that backs up using the volumes managed by docker. at that point you are using bind mounts again anyway.
regarding your original question, i don't think it is possible (or even useful) to tell docker where to store the volumes for each compose stack because you are not supposed to access the from the filesystem directly anyway.
just continue using bind mounts
tbh...I hate volumes. I prefer having my docker data in my home folder, which I do regularly back up
@Pete90 There is plugins you can use to tell docker where your volumes are. Something like this works for local directories:
Docker will create a _data directory as usual.
volumes:
web_data:
db_data:
driver: local # Define the driver and options under the volume name
driver_opts:
type: none
device: /data/myservice/db_data
o: bind
this is a bind mount, defining them like this in a compose file is for when multiple containers share volumes, you just need to write the name of the volume instead of the path, but...
is not that much less than
🤷
@ErwinLottemann I like named volumes in my compose files better thou, keep them organised under the volume section and manageable with docker-cli if needed.
Ah, so I basically specify with driver and it's option(s) where to save the volume. I'll play around with it for a bit and see where it goes. Thanks!