0. Prepare config and download directories with following commands.

   mkdir /storage/aria2/config
   chown -R 1001:1002 /storage/aria2/config
   find /storage/aria2/config -type d -exec chmod 755 {} +
   find /storage/aria2/config -type f -exec chmod 644 {} +
   mkdir /storage/aria2/downloads
   chown -R 1001:1002 /storage/aria2/downloads
   find /storage/aria2/downloads -type d -exec chmod 755 {} +
   find /storage/aria2/downloads -type f -exec chmod 644 {} +

1. Put aria2.conf file in the config dir, with following content.

   save-session=/config/aria2.session
   input-file=/config/aria2.session
   save-session-interval=60
   
   dir=/downloads
   
   file-allocation=prealloc
   disk-cache=128M
   
   enable-rpc=true
   rpc-listen-port=6800
   rpc-allow-origin-all=true
   rpc-listen-all=true
   
   rpc-secret=<password>
   
   auto-file-renaming=false
   
   max-connection-per-server=16
   min-split-size=1M
   split=16

2. Run following command to start aria2 instance

   docker run \
     -d \
     --name aria2 \
     -u=1001:1002 \
     -v /storage/aria2/config:/config \
     -v /storage/aria2/downloads:/downloads \
     -p 6800:6800 \
     opengg/aria2

Note:

• Make sure the download folder is writable by the given uid/gid.
• aria2.conf will be created automatically if not exists.
• Learn more about tuning aria2.conf: Config reference

The parameters are split into two halves, separated by a colon, the left hand side representing the host and the right the container side. For example with a port -p external:internal - what this shows is the port mapping from internal to external of the container. So -p 8080:80 would expose port 80 from inside the container to be accessible from the host's IP on port 8080 http://192.168.x.x:8080 would show you what's running INSIDE the container on port 80.

• -p 6800:6800 - the port(s)
• -v /storage/aria2/config:/config - where aria2 should store config files and logs
• -v /storage/aria2/downloads:/downloads - local path for downloads
• -u 1001 for UserID - see below for explanation
• -u 1001:1002 for GroupID - see below for explanation

It is based on alpine linux, for shell access whilst the container is running do docker exec -it aria2 /bin/sh.

Sometimes when using data volumes (-v flags) permissions issues can arise between the host OS and the container. We avoid this issue by allowing you to specify the user. Ensure the data volume directory on the host is owned by the same user you specify and it will "just work" ™.

In this instance -u 1001:1002. To find yours use id user as below:

  $ id dockeruser
    uid=1001(dockeruser) gid=1002(dockergroup) groups=1002(dockergroup)