A battle-tested solution for respawning node services on SysVinit-based (init.d) systems like Debian.
The scripts assume the following configuration (you might adjust the paths):
- The server script is server.js
- The server runs as user www-data (i.e. no privileged ports)
- The server listens on port
10080, but is redirected from port80(via iptables) - Node is installed in
/opt/nodejs/v0.10 - All output is logged to
/var/log/node-service.log
Some TCP tweaks are done in the init script. This allows us to use many connections (open files) and reduce the timeouts, so e.g. broken WebSocket connections don't stay at the server for 2 hours.
# To allow many connections
ulimit -n 32767
# TCP tweaks
sysctl -q -w net.ipv4.tcp_retries2=5 # 15
sysctl -q -w net.ipv4.tcp_keepalive_time=300 # 7200
sysctl -q -w net.ipv4.tcp_keepalive_probes=2 # 9
sysctl -q -w net.ipv4.tcp_keepalive_intvl=5 # 75
As we cannot listen on port 80 as non-root user, we have to redirect port 80 to 10080 (where the server listens):
# Redirect privileged ports
iptables -t nat -I PREROUTING -p tcp --dport 80 -j REDIRECT --to-port 10080
This can of course be commented out if redirection is done with a load balancer like nginx.
The node-service.sh script restarts the node process when it crashes. The same can be achieved with forever, but I did not find a good way to run forever from an init script.