I have a need to start a script on an http get request from an external machine and I'm using Node.js for this. I want the server to start with the system. Everything is working except that it appears the the server is being started too early in the boot process:
-- Logs begin at Mon 2017-01-23 09:55:21 UTC, end at Mon 2017-01-23 10:36:20 UTC. --
Jan 23 09:55:24 powercontrol systemd[1]: Starting Energenie Listener...
Jan 23 09:55:24 powercontrol systemd[1]: Started Energenie Listener.
Jan 23 09:55:28 powercontrol node[474]: events.js:160
Jan 23 09:55:28 powercontrol node[474]: throw er; // Unhandled 'error' event
Jan 23 09:55:28 powercontrol node[474]: ^
Jan 23 09:55:28 powercontrol node[474]: Error: listen EADDRNOTAVAIL 192.168.40.62:8001
Jan 23 09:55:28 powercontrol node[474]: at Object.exports._errnoException (util.js:1022:11)
Jan 23 09:55:28 powercontrol node[474]: at exports._exceptionWithHostPort (util.js:1045:20)
Jan 23 09:55:28 powercontrol node[474]: at Server._listen2 (net.js:1249:19)
Jan 23 09:55:28 powercontrol node[474]: at listen (net.js:1298:10)
Jan 23 09:55:28 powercontrol node[474]: at doListening (net.js:1397:7)
Jan 23 09:55:28 powercontrol node[474]: at _combinedTickCallback (internal/process/next_tick.js:77:11)
Jan 23 09:55:28 powercontrol node[474]: at process._tickCallback (internal/process/next_tick.js:98:9)
Jan 23 09:55:28 powercontrol node[474]: at Module.runMain (module.js:607:11)
Jan 23 09:55:28 powercontrol node[474]: at run (bootstrap_node.js:420:7)
Jan 23 09:55:28 powercontrol node[474]: at startup (bootstrap_node.js:139:9)
Jan 23 09:55:28 powercontrol systemd[1]: energenie_listener.service: main process exited, code=exited, s
Jan 23 09:55:28 powercontrol systemd[1]: Unit energenie_listener.service entered failed state.
Jan 23 09:55:30 powercontrol systemd[1]: energenie_listener.service holdoff time over, scheduling restar
Jan 23 09:55:30 powercontrol systemd[1]: Stopping Energenie Listener...
Jan 23 09:55:30 powercontrol systemd[1]: Starting Energenie Listener...
Jan 23 09:55:30 powercontrol systemd[1]: Started Energenie Listener.
Jan 23 09:55:31 powercontrol node[565]: events.js:160
Jan 23 09:55:31 powercontrol node[565]: throw er; // Unhandled 'error' event
Jan 23 09:55:31 powercontrol node[565]: ^
Jan 23 09:55:31 powercontrol node[565]: Error: listen EADDRNOTAVAIL 192.168.40.62:8001
Jan 23 09:55:31 powercontrol node[565]: at Object.exports._errnoException (util.js:1022:11)
Jan 23 09:55:31 powercontrol node[565]: at exports._exceptionWithHostPort (util.js:1045:20)
Jan 23 09:55:31 powercontrol node[565]: at Server._listen2 (net.js:1249:19)
Jan 23 09:55:31 powercontrol node[565]: at listen (net.js:1298:10)
Jan 23 09:55:31 powercontrol node[565]: at doListening (net.js:1397:7)
Jan 23 09:55:31 powercontrol node[565]: at _combinedTickCallback (internal/process/next_tick.js:77:11)
Jan 23 09:55:31 powercontrol node[565]: at process._tickCallback (internal/process/next_tick.js:98:9)
Jan 23 09:55:31 powercontrol node[565]: at Module.runMain (module.js:607:11)
Jan 23 09:55:31 powercontrol node[565]: at run (bootstrap_node.js:420:7)
Jan 23 09:55:31 powercontrol node[565]: at startup (bootstrap_node.js:139:9)
Jan 23 09:55:31 powercontrol systemd[1]: energenie_listener.service: main process exited, code=exited, s
Jan 23 09:55:31 powercontrol systemd[1]: Unit energenie_listener.service entered failed state.
Jan 23 09:55:33 powercontrol systemd[1]: energenie_listener.service holdoff time over, scheduling restar
Jan 23 09:55:33 powercontrol systemd[1]: Stopping Energenie Listener...
Jan 23 09:55:33 powercontrol systemd[1]: Starting Energenie Listener...
Jan 23 09:55:33 powercontrol systemd[1]: Started Energenie Listener.
Jan 23 09:55:34 powercontrol node[572]: Server running at http://192.168.40.62:8001/
As you can see, after a couple of failures, the server eventually starts and it works fine after that. The .service
file is as follows:
[Unit]
Description=Energenie Listener
After=network.target systemd-journald.service
[Service]
ExecStart=/usr/bin/node /var/opt/energenie/energenie_listener.js
Restart=always
RestartSec=2
User=root
Group=root
Environment=PATH=/usr/bin:/usr/local/bin
Environment=NODE_ENV=production
WorkingDirectory=/var/opt/energenie
[Install]
WantedBy=multi-user.target
As well as After=network.target ...
, I tried network-online.target
, but it makes no difference.
Should I be waiting for a different service? Which one?
I do have one thought: this machine has a static IP but it's assigned via DHCP. If the problem is that network.target
(and network-online.target
) is up but the IP I'm trying to claim in the Node script is not yet assigned, presumably I need a service to wait on which will guarantee that the IP address is fully configured. Could this be the problem, and if so, is there a suitable service to depend on?