systemd/user/backdoor@.service

   1 [Unit]
   2 Description=Reverse SSH Tunnel Service
   3 After=network.target
   4 StartLimitIntervalSec=30m
   5 StartLimitBurst=5
   6
   7 [Service]
   8 ExecStart=/usr/bin/ssh -i ~/.ssh/id_ed25519_port-forward -NT -o ServerAliveInterval=60 -o ExitOnForwardFailure=yes -R 22222:localhost:22 %i
   9 Restart=always
  10 RestartSec=5m
  11
  12 [Install]
  13 WantedBy=default.target