Moved the /system directory to another place on disk

[tbolon]

I have a VM where the OS disk is small, and I don't want to use it for the /system directory, where a lot of files will be dropped.

Instead, I have a large disk mounted on /datadrive. Here are all the steps I have used to customize mastodon. I am completely new to nginx / sidekiq / systemd so there was certainly a simplier solution. Feel free to comment!

Initial setup:

• I have a root user and a mastodon user, as recommended
• mastodon is installed on ~/live directory for the mastodon user
• I have a /datadrive mounted and created a /datadrive/mastodon-public/ directory owned by mastodon/mastodon with chmod 775

Steps:

Give write access to systemd

Using your root user.

It's the main problem I have faced. Because systemd sandbox write access, the services won't have access to your datadrive. It's the reason why #20228 did not work. There is an explanation on a PR of the documentation about that: https://github.com/mastodon/documentation/pull/892/files

You have to do as suggested, and edit your /etc/systemd/system/mastodon-web.service and /etc/systemd/system/mastodon-sidekiq.service to give write permission to /datadrive/mastodon-public/.

In my case : ReadWritePaths=/home/mastodon/live /datadrive/mastodon-public

You have to restart all services and systemd after that:

systemctl stop mastodon-sidekiq mastodon-web
systemctl daemon-reload
systemctl start mastodon-sidekiq mastodon-web

RSync your files

You should start an initial copy of your files. Using your mastodon account.

rsync ~/live/public/system /datadrive/mastodon-public/system/ -r

Update nginx config

It's another tricky part, and the section where I am sure there are other most simple options.

Edit your nginx.conf to add the following parts (for v4):

  location ~ ^/system/ {
    add_header Cache-Control "public, max-age=2419200, immutable";
    add_header Strict-Transport-Security "max-age=63072000; includeSubDomains";
    root /datadrive/mastodon-public/;
    try_files $uri =404;
  }

For v3.5 (my case), it's more complex, because I wanted to keep the custom headers for some directories:

  # initally this location match both emojis, packs and some system directories. now it only matches non moved directories
  location ~ ^/(emoji|packs) {
    add_header Cache-Control "public, max-age=31536000, immutable";
    add_header Strict-Transport-Security "max-age=31536000" always;
    try_files $uri @proxy;
  }

  # here we have isolated the system directories to both apply http headers AND move the root
  location ~ ^/(system/accounts/avatars|system/media_attachments/files) {
    add_header Cache-Control "public, max-age=31536000, immutable";
    add_header Strict-Transport-Security "max-age=31536000" always;
    root /datadrive/mastodon-public;
    try_files $uri @proxy;
  }

  # and finally all remaining system directories are redirected to roor
  location ~ ^/(system) {
    root /datadrive/mastodon-public;
    try_files $uri @proxy;
  }

There are a lot of other changes in the v4 that could be applied here.

Edit PAPERCLIP settings

Paperclip is responsible to manage media.

PAPERCLIP_ROOT_PATH=/datadrive/mastodon-public/system/
PAPERCLIP_ROOT_URL=/system

Reload mastodon and nginx

nginx -s reload
sudo systemctl restart mastodon-sidekiq
sudo systemctl reload  mastodon-web

Repeat a final rsync

To copy the remaining files

Rename system/ folder as system.bak/

Check that there is no error / 404

Erase system.bak

[dogrileycom]

Thanks, this was helpful. A few notes:

typo in the V4 nginx location it is missing a ;
root /datadrive/mastodon-public/`

I used the V4 method, edited the .env.production file directly

I ran into 1 user issue and that was trying to use the same path in nginx and .env.production, nginx only need to /public and .env needs to system/ when I realized that it all worked!!

Thanks

[tbolon]

root /datadrive/mastodon-public/`

fixed thanks.

I ran into 1 user issue and that was trying to use the same path in nginx and .env.production, nginx only need to /public and .env needs to system/ when I realized that it all worked!!

Yes, it's tricky about the /public/system and the /system directory... I missed it a few times also.

[kpfleming]

As of the release of Mastodon 4.1.3 it is strongly suggested to add some additional headers for the /system path; see #25756 for details.

[allilengyi]

Thanks, this really helped fixed some issues.