Managing services and applications at startup in GNU / Linux

The Init scripts are small shell programs that normally control services, also known as daemons. Other applications include init scripts simply monitor the status of something like eg. hdparm (sleep times hard drives), iptables (firewall rules loaded into the kernel) and setserial (COM port settings). The /etc/init.d directory contains the scripts executed by init during the boot process and when it starts working init.

The Init scripts are also important during on and off (just change runlevel * nix systems). If we take a look at the list of processes running on our GNU / Linux system (eg. Ps auwx), we will see in the process list one called init with the lowest PID. This is the parent of all processes; This is the first program that the kernel executes when the system boots. Init, which is located in / sbin / init, you are responsible to have the system up and running after the kernel boot process completes.

Now we will see some tools to manage our init scripts, either to deternerlos, or take them on startup.

Startup Applications Preferences

It is the most critical to configure some of the services and applications that are started from startup tool. It can only control the main user services, about 23, but GNU / Linux can hold hundreds of different services in each runlevel (/ etc / init .d /).

rcconf

Rcconf allows us to control which services are started when the system boots. It shows a menu with all the services that can be started. Those that are configured to start are marked and can change each service either to turn it on or off. This tool configures system services directly with runlevels. Rcconf services on or off utilizandos the scripts located in /etc/init.d/, working with the configuration to the System-V style. Rcconf is a TUI (Text User Interface) for the update-rc.d command.

Rcconf gets the list of services /etc/init.d takes a look in the directories /etc/rc?.d to determine whether each service is enabled or disabled.

Create Boot Manager

It is based on Perl-Gtk2, is an application to manage the configuration of the runlevels any Debia or derivative system. We can easily start and stop init scripts without the need to engage with complex links and form root permissions.

sysv-rc-conf

Definitely the best tool for this purpose, enabling us to monitor all services and determine which runleven are to start. But there is a problem (at least for some): like rcconf, is based on command line and text mode. Provides more information about each service.

A command clean!

Debian | Ubuntu

Set the default MySQL daemon

$ Sudo update-rc.d -f mysql defaults

Configure MySQL daemon to start in runlevel 2 3 4 5 not do so in 0 1 6

$ Sudo update-rc.d mysql start 20 2 3 4 5. stop 80 0 1 6.

Configure MySQL daemon not to start

$ Sudo update-rc.d -f remove mysql

RedHat | Fedora | CentOS

Set squid3 daemon not to start

$ Sudo chkconfig off squid3

Set squid3 daemon to start in runlevels 2 May 3

$ Sudo chkconfig --level squid3 2 May 3 on

These were the most popular scripts for configuring the beginning of our GNU / Linux system tools. A graphical others in command lines, each delivers. If you know any other not mentioned here, you can let us know by a comment!