Rápido recordatorio de encontrar fácilmente (no es 100% seguro, dependerá de las distros) si estamos usando systemd/upstart/systemV
if [[ `/sbin/init --version` =~ upstart ]]; then echo using upstart;
elif [[ `systemctl` =~ -\.mount ]]; then echo using systemd;
elif [[ -f /etc/init.d/cron && ! -h /etc/init.d/cron ]]; then echo using sysv-init;
else echo cannot tell; fistrings /sbin/init | grep -q "/lib/systemd" && echo SYSTEMD
strings /sbin/init | grep -q "sysvinit" && echo SYSVINIT
strings /sbin/init | grep -q "upstart" && echo UPSTARTMáquina de pruebas es una Amazon Linux AMI release 2017.09
El primer test
# bash check_bash.sh
using upstart
El segundo test
UPSTART
El caso en concreto para este Linux AWS AMI es que funciona con una mezcla de systemV y upstart y me despistó un poco. Un ejemplo de upstart script sería:
description "node-exporter from prometheus"
start on filesystem or runlevel [2345]
stop on runlevel [!2345]
respawn
umask 022
chdir /
# console log - uncomment log stdout/stderr to /var/log/upstart/
# console none # Ubuntu 12.04++ requires explicitly saying we don't want to log anything
exec /usr/local/bin/node_exporter
Listar servicios
# initctl list
Arrancar upstart service
# sudo initctl start node-export
node-export start/running, process 21704
Comprobar upstart service
# sudo initctl status node-export
node-export start/running, process 21704
El mismo caso pero en systemd
[Unit]
Description=Node Exporter
[Service]
User=prometheus
ExecStart=/usr/local/bin/node_exporter
[Install]
WantedBy=default.target
# systemctl daemon-reload
# systemctl enable node_exporter.service
# systemctl start node_exporter.service
Links
- https://unix.stackexchange.com/questions/18209/detect-init-system-using-the-shell
- https://www.linode.com/docs/quick-answers/linux/start-service-at-boot/
- https://github.com/prometheus/node_exporter/blob/master/examples/systemd/node_exporter.service
