systemd 経由での自動起動設定

/etc/systemd/system/httpd.service ファイルを作成して、以下を記述。

# cat  /etc/systemd/system/httpd.service
[Unit]
Description=The Apache HTTP Server
After=network.target remote-fs.target nss-lookup.target

[Service]
Type=forking
ExecStart=/usr/local/apache2/bin/apachectl -k start
ExecReload=/usr/local/apache2/bin/apachectl graceful
ExecStop=/usr/local/apache2/bin/apachectl -k stop
PrivateTmp=true
Restart=always
OOMScoreAdjust=-1000

[Install]
WantedBy=multi-user.target

# systemctl status httpd
● httpd.service - The Apache HTTP Server
   Loaded: loaded (/etc/systemd/system/httpd.service; disabled; vendor preset: disabled)
   Active: active (running) since 土 2017-05-27 12:10:59 JST; 5min ago
  Process: 3805 ExecStart=/usr/local/apache2/bin/apachectl -k start (code=exited, status=0/SUCCESS)
 Main PID: 3808 (httpd)
   CGroup: /system.slice/httpd.service
           ├─3808 /usr/local/apache2/bin/httpd -k start
           ├─3809 /usr/local/apache2/bin/httpd -k start
           ├─3810 /usr/local/apache2/bin/httpd -k start
           └─3817 /usr/local/apache2/bin/httpd -k start

 5月 27 12:10:59 v*****.vir.kagoya.net systemd[1]: Starting The Apache HTTP Server...
 5月 27 12:10:59 v*****.vir.kagoya.net systemd[1]: Started The Apache HTTP Server.

Loaded: loaded (/etc/systemd/system/httpd.service; disabled; vendor preset: disabled)
と、
/etc/systemd/system/httpd.service; disabled
なので、サーバー起動時に自動起動しない。

# systemctl enable httpd
Created symlink from /etc/systemd/system/multi-user.target.wants/httpd.service to /etc/systemd/system/httpd.service.

# systemctl status httpd
● httpd.service - The Apache HTTP Server
   Loaded: loaded (/etc/systemd/system/httpd.service; enabled; vendor preset: disabled)
   Active: active (running) since 土 2017-05-27 12:10:59 JST; 6min ago
 Main PID: 3808 (httpd)
   CGroup: /system.slice/httpd.service
           ├─3808 /usr/local/apache2/bin/httpd -k start
           ├─3809 /usr/local/apache2/bin/httpd -k start
           ├─3810 /usr/local/apache2/bin/httpd -k start
           └─3817 /usr/local/apache2/bin/httpd -k start

 5月 27 12:10:59 v*****.vir.kagoya.net systemd[1]: Starting The Apache HTTP Server...
 5月 27 12:10:59 v*****.vir.kagoya.net systemd[1]: Started The Apache HTTP Server.

のように、
systemctl enable httpd
で、自動起動設定。
Loaded: loaded (/etc/systemd/system/httpd.service; enabled
と、enabled になった。

設定ファイルを更新したら、
systemctl daemon-reload
で、デーモン再起動して、設定ファイルを読み込ませる。