# Ficheiro de exemplo para o exercício Z6.2 (curso VPS e administração de servidores Linux)
# Servidor "web1" (Debian 13). Um serviço próprio que executa uma pequena aplicação web.

anna@web1:~$ systemctl status factuurapp
× factuurapp.service - Factuurapp (Node.js)
     Loaded: loaded (/etc/systemd/system/factuurapp.service; enabled; preset: enabled)
     Active: failed (Result: exit-code) since Mon 2026-11-09 10:15:07 CET; 12min ago
   Duration: 412ms
    Process: 2291 ExecStart=/usr/bin/node /opt/factuurapp/server.js (code=exited, status=1/FAILURE)
   Main PID: 2291 (code=exited, status=1/FAILURE)
        CPU: 389ms

anna@web1:~$ sudo journalctl -u factuurapp --since "2026-11-09 10:14" --no-pager
nov 09 10:15:01 web1 systemd[1]: Started factuurapp.service - Factuurapp (Node.js).
nov 09 10:15:01 web1 node[2240]: Factuurapp 3.2.0 start op 127.0.0.1:3000
nov 09 10:15:01 web1 node[2240]: Error: listen EADDRINUSE: address already in use 127.0.0.1:3000
nov 09 10:15:01 web1 node[2240]:     at Server.setupListenHandle [as _listen2] (node:net:1908:16)
nov 09 10:15:02 web1 systemd[1]: factuurapp.service: Main process exited, code=exited, status=1/FAILURE
nov 09 10:15:02 web1 systemd[1]: factuurapp.service: Failed with result 'exit-code'.
nov 09 10:15:03 web1 systemd[1]: factuurapp.service: Scheduled restart job, restart counter is at 1.
nov 09 10:15:03 web1 systemd[1]: Started factuurapp.service - Factuurapp (Node.js).
nov 09 10:15:03 web1 node[2252]: Error: listen EADDRINUSE: address already in use 127.0.0.1:3000
nov 09 10:15:03 web1 systemd[1]: factuurapp.service: Main process exited, code=exited, status=1/FAILURE
nov 09 10:15:03 web1 systemd[1]: factuurapp.service: Failed with result 'exit-code'.
nov 09 10:15:04 web1 systemd[1]: factuurapp.service: Scheduled restart job, restart counter is at 2.
nov 09 10:15:04 web1 systemd[1]: Started factuurapp.service - Factuurapp (Node.js).
nov 09 10:15:05 web1 node[2266]: Error: listen EADDRINUSE: address already in use 127.0.0.1:3000
nov 09 10:15:05 web1 systemd[1]: factuurapp.service: Main process exited, code=exited, status=1/FAILURE
nov 09 10:15:05 web1 systemd[1]: factuurapp.service: Failed with result 'exit-code'.
nov 09 10:15:06 web1 systemd[1]: factuurapp.service: Scheduled restart job, restart counter is at 3.
nov 09 10:15:06 web1 systemd[1]: Started factuurapp.service - Factuurapp (Node.js).
nov 09 10:15:06 web1 node[2279]: Error: listen EADDRINUSE: address already in use 127.0.0.1:3000
nov 09 10:15:06 web1 systemd[1]: factuurapp.service: Main process exited, code=exited, status=1/FAILURE
nov 09 10:15:06 web1 systemd[1]: factuurapp.service: Failed with result 'exit-code'.
nov 09 10:15:07 web1 systemd[1]: factuurapp.service: Scheduled restart job, restart counter is at 4.
nov 09 10:15:07 web1 systemd[1]: Started factuurapp.service - Factuurapp (Node.js).
nov 09 10:15:07 web1 node[2291]: Error: listen EADDRINUSE: address already in use 127.0.0.1:3000
nov 09 10:15:07 web1 systemd[1]: factuurapp.service: Main process exited, code=exited, status=1/FAILURE
nov 09 10:15:07 web1 systemd[1]: factuurapp.service: Failed with result 'exit-code'.
nov 09 10:15:07 web1 systemd[1]: factuurapp.service: Start request repeated too quickly.
nov 09 10:15:07 web1 systemd[1]: factuurapp.service: Failed with result 'exit-code'.
nov 09 10:15:07 web1 systemd[1]: Failed to start factuurapp.service - Factuurapp (Node.js).

anna@web1:~$ sudo ss -tlnp | grep 3000
LISTEN 0 511 127.0.0.1:3000 0.0.0.0:* users:(("node",pid=1187,fd=21))

Perguntas:
1. Qual é o nome do serviço (a unit)?
2. Quantas vezes, no total, foi o serviço iniciado (linhas Started)?
3. Com que código de saída (status) terminou o programa?
4. Segundo a primeira mensagem de erro, qual é a causa?
   a. O ficheiro server.js não existe
   b. A porta 3000 em 127.0.0.1 já está a ser utilizada por outro processo
   c. O servidor tem pouca memória
   d. O serviço está a ser executado com o utilizador errado
5. A que horas (hh:mm:ss) desistiu o systemd de reiniciar o serviço?
6. Que processo está a ocupar a porta (pid)?