Ubuntu开机启动的方式

方法一：
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1. 在/etc/init.d/下放置启动脚本，比如postgresql
root@ubuntu:/etc/init.d# cat postgresql
#!/bin/sh
set -e

### BEGIN INIT INFO
# Provides: postgresql
# Required-Start: $local_fs $remote_fs $network $time
# Required-Stop: $local_fs $remote_fs $network $time
# Should-Start: $syslog
# Should-Stop: $syslog
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Short-Description: PostgreSQL RDBMS server
### END INIT INFO

# Setting environment variables for the postmaster here does not work; please
# set them in /etc/postgresql/<version>/<cluster>/environment instead.

[ -r /usr/share/postgresql-common/init.d-functions ] || exit 0

. /usr/share/postgresql-common/init.d-functions

# versions can be specified explicitly
if [ -n "$2" ]; then
versions="$2 $3 $4 $5 $6 $7 $8 $9"
else
get_versions
fi

case "$1" in
start|stop|restart|reload)
if [ "$1" = "start" ]; then
create_socket_directory
fi
if [ -z "`pg_lsclusters -h`" ]; then
log_warning_msg 'No PostgreSQL clusters exist; see "man pg_createcluster"'
exit 0
fi
for v in $versions; do
$1 $v || EXIT=$?
done
exit ${EXIT:-0}
;;
status)
LS=`pg_lsclusters -h`
# no clusters -> unknown status
[ -n "$LS" ] || exit 4
echo "$LS" | awk 'BEGIN {rc=0} {if (match($4, "down")) rc=3; printf ("%s/%s (port %s): %s ", $1, $2, $3, $4)}; END {exit rc}'
;;
force-reload)
for v in $versions; do
reload $v
done
;;
*)
echo "Usage: $0 {start|stop|restart|reload|force-reload|status} [version ..]"
exit 1
;;
esac

exit 0

2. 添加服务
cd /etc/init.d/
update-rc.d postgresql defaults 90

3. 删除启动
update-rc.d -f postgresql remove

方法二
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1. 启动脚本：/etc/systemd/system/postgresql.service
[Unit]
Description=PostgreSQL database server
After=network.target

[Service]
Type=forking
User=postgres
Group=postgres
OOMScoreAdjust=-1000
Environment=PG_OOM_ADJUST_FILE=/proc/self/oom_score_adj
Environment=PG_OOM_ADJUST_VALUE=0
Environment=PGSTARTTIMEOUT=270
Environment=PGDATA=/data/postgresql/data
ExecStart=/usr/local/pgsql/bin/pg_ctl start -D ${PGDATA} -s -w -t ${PGSTARTTIMEOUT}
ExecStop=/usr/local/pgsql/bin/pg_ctl stop -D ${PGDATA} -s -m fast
ExecReload=/usr/local/pgsql/bin/pg_ctl reload -D ${PGDATA} -s
TimeoutSec=300

[Install]
WantedBy=multi-user.target

2. 添加启动
systemctl daemon-reload
systemctl enable postgresql