docs: Add zerotier setup (#244)

Author: Zeglius

mkdocs.yml

@@ -144,6 +144,7 @@ nav:
       - "Reporting Bugs": General/reporting_bugs.md
       - "Desktop Environment Tweaks": General/Desktop_Environment_Tweaks.md
       - "VPN Setup": General/VPN.md
+      - "ZeroTier Setup": General/zerotier.md
       - "Community Resources": General/community-links.md
       - "Uninstalling Bazzite": General/uninstalling-bazzite.md
       - "Repository Information (External)":

src/General/zerotier.md

@@ -0,0 +1,44 @@
+---
+title: "ZeroTier setup"
+authors:
+  - "@Zeglius"
+---
+
+!!! warning
+    Setup requires **layering** and is [not recommended](/Installing_and_Managing_Software/rpm-ostree/#major-caveats-using-rpm-ostree).
+
+## Installing
+
+Select, copy and paste the following to the terminal (pasting is <kbd>Ctrl</kbd>+<kbd>Shift</kbd>+<kbd>V</kbd>)
+
+```sh
+sudo tee >/dev/null /etc/yum.repos.d/zerotier.repo <<'EOF'
+[zerotier]
+name=ZeroTier, Inc. RPM Release Repository
+baseurl=https://repo.zerotier.com/yum/$basearch/
+enabled=1
+gpgcheck=1
+gpgkey=https://download.zerotier.com/contact@zerotier.com.gpg
+EOF
+```
+
+Reboot, and run this at the terminal:
+
+```sh
+systemctl enable zerotier-one.service
+```
+
+## Uninstalling
+
+Select, copy and paste the following to the terminal (pasting is <kbd>Ctrl</kbd>+<kbd>Shift</kbd>+<kbd>V</kbd>)
+
+```sh
+sudo systemctl disable zerotier-one.service
+sudo rpm-ostree uninstall zerotier-one
+```
+
+Reboot, and run this at the terminal:
+
+```sh
+sudo rm -fv /etc/yum.repos.d/zerotier.repo
+```