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service --status-all <===> vypíše všchny služby (+ bezi - nebeží ? nevim) pouze na initV // The status is [ + ] for running services, [ - ] for stopped services and [ ? ] for services without a status command.
ls -al /etc/init.d/ <===> see the listed services from sysvinit system

Jednou z hlavních příčin hledání náhrad za init je fakt, že spouští skripty sériově. To znamená, že následující skript může být spuštěn až po dokončení předchozího skriptu, což může mít následek prodlevy při startu systému.
Toto zpoždění lze zkrátit pomocí SSD disků, ale neřeší příčinu.

The + indicates the service is running, - indicates a stopped service. You can see this by running service SERVICENAME status for a + and - service.

service {sluzba} start
service {sluzba} stop
service {sluzba} restart
service {sluzba} status

chkconfig {sluzba} on
chkconfig {sluzba} off

nejcasteji bezici sluzby:
sudo service rpcbind stop

Long the standard start-up system, init traces its history back to the original Unix systems on which Linux was based (its proper name is SysVInit, drawing from System V Unix).
The init system is based on a collection of start-up scripts, kept in the /etc/init.d or /etc/rc.d directories, and the concept of "runlevels."
For example, desktop-oriented distributions will start you in "runlevel 5," which is defined as "multi-user mode with networking + X display manager."
This is why when you start up one of these distributions, you'll immediately end up with an X-system-based graphical desktop log-in.

The init system adheres to the Unix philosophy, in that it does one thing and does it well. One of the arguments voiced by proponents of the system is that it doesn't try to do too much,
unlike some of the following alternatives.

Enabling / Disabling a service

The traditional way to start services in Linux was to place a script in /etc/init.d, and then use the update-rc.d command (or in RedHat based distros, chkconfig) to enable or disable it.

This command uses some mildly complicated logic to create symlinks in /etc/rc#.d, that control the order of starting services. If you run ls /etc/rc2.d you can see the order that services will be killed with a file name like K##xxxx and started with file names S##xxxx. The ## in S##xxxx means a "start order" for service xxxx. Conversely, the ## in K##xxxx means the kill order for service xxxx.

One major issue with SysV was that when booting the system, everything had to be done in serial, one thing after another, making system boot times really slow. Attempts were made to parallelize this, but they were haphazard and hard to take full advantage of. This was the main reason that Upstart was created.