diff --git a/readme.md b/readme.md index eafb9ad..63b30a8 100644 --- a/readme.md +++ b/readme.md @@ -14,6 +14,27 @@ updates. a login QR code. Scan the code with your phone and authenticate with Tailscale to bring your Deck onto your network. +### Changing the root filesystem after installing Tailscale +This method for installing Tailscale uses [`systemd` system extensions](https://man.archlinux.org/man/systemd-sysext.8.en) +to install files in the otherwise read-only Steam Deck filesystem. A +side-effect is that the `/usr` and `/opt` directories +(and directories like `/bin`, `/lib`, `/lib64`, `/mnt`, and `/sbin`, +that typically link to `/usr` due to [`/usr` merge](https://www.freedesktop.org/wiki/Software/systemd/TheCaseForTheUsrMerge/) +which SteamOS implements) are read-only while system extensions are active, +*even after running `steamos-readonly disable`*. + +If you need to modify files in these directories after installing Tailscale, +run the following commands: + +```bash +$ systemd-sysext unmerge +$ steamos-readonly disable +[ make your changes to the rootfs now ] +$ steamos-readonly enable +$ systemd-sysext merge +``` + + ## Updating Tailscale ⚠️ This process will most likely fail if you are accessing the terminal over