Process layer
System stack
The 24x7 process layer is the uninterruptible core where essential services run. This is where system software like your firewall, your database server, your web server, your domain name system, and your secure shell processes live. When your hardware is functioning properly, these core services should remain up and running without fail, providing anyone with anytime response.
On Linux systems running the Red Hat / CentOS / Fedora family of distros, these services are all available via the services command set. For the Debian, Suse, and Ubuntu Linux distros, the same command set is accessed using the /etc/init.d command set.
To set a set to begin at bootup, use this command: chkconfig <daemon name> on.
Typical commands that may be needed for restarting services after configuration changes:
| service | restart command |
|---|---|
| Apache | httpd -S |
| service httpd graceful | |
| DNS | rndc reload example.com |
| service named restart | |
| Dovecot | service dovecot restart |
| Firewall | service iptables restart |
| MySQL | service mysqld restart |
| network | service network restart |
| SE Linux troubleshoot | service setroubleshootd restart |
| Secure Shell | service sshd restart |
| Sendmail | /etc/mail/make |
| newaliases | |
| service sendmail restart |