We’re using an old version of Upstart, on Centos, to manage stopping and starting our Node.js daemons, and one of the things the script does, like any good deamon, is change the user of the deamon process from root to something more applicable, security and all that 😉
The scripts look a little like this
!upstart
description "Amazing Node.js Daemon"
author "idimmu"
start on runlevel [2345]
stop on shutdown
env PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
env NAME="amazing-daemon"
script
export HOME="/root"
cd /opt/idimmu/$NAME
echo $$ > /var/run/$NAME.pid
exec sudo -u idimmu /usr/bin/node /opt/idimmu/$NAME/server.js >> /var/log/$NAME/stdout.log 2>&1
end script
pre-start script
echo "[`date -u +%Y-%m-%dT%T.%3NZ`] (upstart) Starting $NAME" >> /var/log/$NAME/stdout.log
end script
pre-stop script
rm /var/run/$NAME.pid
echo "[`date -u +%Y-%m-%dT%T.%3NZ`] (upstart) Stopping $NAME" >> /var/log/$NAME/stdout.log
end scriptWhich is nice, as it means we can use Upstart to stop/start/status deamons really nicely. The equivalent init.d script looked really horrible.
But there’s one massive caveat, which we always encounter when building a brand new box, from scratch.
2013-09-27T10:50:10.174Z] (upstart) Starting amazing-daemon
sudo: sorry, you must have a tty to run sudosudo: sorry, you must have a tty to run sudo
So it all falls apart due to the following error:
sudo: sorry, you must have a tty to run sudo
Basically sudo is stopping the process from running because Upstart doesn’t have a TTY. This is easily fixable. Just edit /etc/sudoers using visudo and comment out
Defaults requirettyi.e.
#Defaults requirettyNow we can use Upstart to start the daemon and check it’s status to confirm it’s running! More recent versions of Upstart don’t need this hack. One day I’ll live in the future, but not today.
deploy:amazing root$ start amazing
amazing start/running, process 3965
deploy:amazing root$ status amazing
amazing start/running, process 3965Bamo, problem solved!