Tailscale Auto Cert Update Service These systemd services allow me to update the Tailscale certificates for PiKVM every 80 days without manual intervention. cert-update.timer [Unit] Description=Update tailscale certificates for nginx [Timer] OnBootSec=1min OnUnitActiveSec=80d AccuracySec=1h Persistent=true [Install] WantedBy=timers.target tailscale-cert-update.service [Unit] Description=Update tailscale certificates for nginx After=network-online.target tailscaled.service [Service] Type=oneshot # Service isolation ProtectHome=true ReadWritePaths=/etc/kvmd/nginx/ssl PrivateNetwork=false ProtectClock=true ProtectHostname=true ProtectKernelTunables=true ProtectKernelModules=true ProtectControlGroups=true LockPersonality=true # Execution steps ExecStartPre=/usr/bin/curl --silent --max-time 10 --retry 5 https://hc.its-et.me/ping/PlGPBqq-0rLI4N4ya3jYmg/pve-01k-certificate-update/start ExecStartPre=/usr/bin/rw ExecStart=tailscale cert --cert-file=/etc/kvmd/nginx/ssl/server.crt --key-file=/etc/kvmd/nginx/ssl/server.key pve-01k.tail755c5.ts.net ExecStartPost=/usr/bin/curl --silent --max-time 10 --retry 5 https://hc.its-et.me/ping/PlGPBqq-0rLI4N4ya3jYmg/pve-01k-certificate-update ExecStartPost=/usr/bin/systemctl restart kvmd-nginx.service ExecStartPost=/usr/bin/ro [Install] WantedBy=default.target Don't use PrivateDevices= in [Service], this disallows /usr/bin/ro and /usr/bin/rw from executing properly