A server will not come online
A registered server that never appears online, or drops out later. In practice this is one of four things, and the first is by far the most common.
1 · Port 80 is closed
curl -sS -m 5 -i http://YOUR.SERVER.IP/ping
A response means the path is open. A timeout means a firewall, a security group, or a cloud network ACL is in the way — check the provider’s firewall as well as the host’s, since both have to allow it.
2 · The IP does not match the licence
A licence is bound to the address you entered when registering the server. If that address was mistyped, or the machine sits behind NAT and its public address differs from what you registered, the engine will start but never be recognised.
Compare the address on the server against the one in Cipher:
curl -sS https://api.ipify.org; echo
If they differ, remove the server in Cipher and register it again with the correct address. The licence cannot be repointed.
3 · The engine is not running
sudo systemctl status lf-engine sudo journalctl -u lf-engine -n 100 --no-pager
sudo env "PATH=$PATH" pm2 logs lockflare --lines 100
A licence problem appears in these logs explicitly. So does a missing runtime — Node 24 or the ASP.NET Core 10 runtime.
4 · Node only: the web server in front is down
The Node engine listens on port 3000 behind nginx. If nginx is not running, port 80 answers nothing even though the engine is healthy.
sudo systemctl status nginx sudo nginx -t curl -sS -i http://127.0.0.1:3000/ping
If the last command answers but the public IP does not, the problem is nginx or the firewall, not LockFlare. The .NET engine binds port 80 directly and has no reverse proxy, so this step does not apply.