referencing accessories by container name?

[gammons]

Hi there,

What's the best way to reference accessories? As far as I understand it, the only option to reference an accessory is by its internal, docker-based ip address. That isn't ideal for a lot of reasons. Does (or could) kamal create a bridge network so that running containers can reference accessories by their container name? Or am I not understanding something? Thanks!

[acidtib]

@gammons This can be achieved if you run the web app and accessory on the same server, create a docker network on the server, then define the network on deploy.yml

create a network on the server
docker network create -d bridge private

set server and accessory network config

servers:
  web:
    hosts:
      - xx.xx.xx.xx
    options:
      network: "private"

accessories:
  db:
    image: mariadb:latest
    host: xx.xx.xx.xx
    port: 3306
    env:
      clear:
        MYSQL_ROOT_HOST: '%'
      secret:
        - MYSQL_ROOT_PASSWORD
        - MYSQL_USER
        - MYSQL_PASSWORD
        - MYSQL_DATABASE
    options:
      network: "private"
    directories:
      - data:/var/lib/mysql

[gammons]

That's perfect @acidtib . Thank you!

[corvuszero]

As stated here: If you have a host and need to call an accessory: Deploy the accessory to that same host and set its options.network-alias in deploy.yml, this way you can call it using that same network alias in the main app. I have an accessory that only a specific role needs so this was very useful.

[geetotes]

As an alternative to setting up a docker network, you could also use the service param in the accessory definition

accessories:
  tika:
    host: xx.xx.xx.xx
    service: tika
    image: apache/tika:latest
    port: "127.0.0.1:9998:9998"

Assuming that this accessory is on the same host as the main "web" application, assigning the string tika to the service param allows me to access it from my rails app with `http://tika:9998"

(if you omit the service param, the networking will default to <service-name>-<accessory> as defined here

[charnould]

Hello,
I tried to use your solution to serve Ollama (I want to be able to fetch('http://localhost:11434/api from my app):

accessories:
  ollama:
    service: ollama
    image: ollama/ollama
    host: 157.90.xxx.xxx (my IP)
    port: '127.0.0.1:11434:11434'

Then kamal accessory boot ollama

But I got this error:

ERROR (SSHKit::Command::Failed): Exception while executing on host 157.90.xxx.xxx: docker exit status: 125 docker stdout: Nothing written docker stderr: flag needs an argument: 'p' in -p

The message doesn't give clues...
Any idea?
Thanks.

[geetotes]

Are you missing :latest when you define the ollama image?

i.e.
image: ollama/ollama:latest

[charnould]

Thanks. I think it was port.
This works:

accessories:
  ollama:
    service: ollama
    image: ollama/ollama
    host: your-ip