Take the 2-minute tour ×
Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems.. It's 100% free, no registration required.

In Windows I have the services manager, where I see all system services, that can be started through Windows itself, I set up the user it uses, the rights management is in there, and I can pass variables and some other information to the services, I can name them, and I can create duplicates services of one program and so on. So I have a main management tool in Windows.

How can I do the same in Linux? How can I trigger to run "svnserve" at startup, or how can I configure services to be running in a special context. How can I view all "programmed" services?

share|improve this question
6  
What distribution and version are you using? Service management (services are almost always called ‘daemons’ in the Unix world) used to be easy and semi-standard. Things are more varied these days. And not always nice. :) Also, what do you mean by context? –  Alexios Dec 26 '13 at 12:01
    
Though it does seem that systemd is slowly winning the init system war. Debian is the last big holdout still using the old SysVinit, and is currently in the process of determining which init system to go with. –  Patrick Dec 26 '13 at 13:59
    
Currently I work with Debian (latest stable), and by context I mean path-variables or a specified user-context. –  Erdinc Ay Dec 26 '13 at 23:23
add comment

3 Answers

up vote 6 down vote accepted

There are currently 3 main init systems used by linux. A few years ago, there was just one, SysVinit. But SysVinit was seriously lacking in capabilities such as service dependency graphing, so it's been deprecated in most distros by now. Currently most distros are either switching to systemd or upstart. Debian is the last major distro still using the old SysVinit, and is currently in the process of debating which system to go with.

But here's the answer to your question for each of the 3 init systems:

 

SysVinit

SysVinit currently used by Debian and RedHat. Though the next version of RedHat will be using systemd.

The univeral way of enabling SysVinit services on boot is to symlink them in /etc/rc3.d. All services can be found in /etc/init.d. Note however that distros will often have their own tool for managing these files, and that tool should be used instead. (Fedora/RedHat has service and chkconfig, ubuntu has update-rc.d)

List services:

ls /etc/init.d/

Start service:

/etc/init.d/{SERVICENAME} start

Stop service:

/etc/init.d/{SERVICENAME} stop

Enable service:

cd /etc/rc3.d
ln -s ../init.d/{SERVICENAME} S95{SERVICENAME}

(the S95 is used to specify order. S01 will start before S02, etc)

Disable service:

rm /etc/rc3.d/*{SERVICENAME}

 

Systemd

List services:

systemctl list-unit-files

Start service:

systemctl start {SERVICENAME}

Stop service:

systemctl stop {SERVICENAME}

Enable service:

systemctl enable {SERVICENAME}

Disable service:

systemctl disable {SERVICENAME}

 

Upstart

List services:

initctl list

Start service:

initctl start {SERVICENAME}

Stop service:

initctl stop {SERVICENAME}

Enable service:

2 ways unfortunately:

  1. There will be a file /etc/default/{SERVICENAME} which contains a line ENABLED=.... Change this line to ENABLED=1.

  2. There will be a file /etc/init/{SERVICENAME}.override. Make sure it contains start (or is absent entirely), not manual.

Disable service:

echo manual > /etc/init/{SERVICENAME}.override

Note: There is also the 'OpenRC' init system which is used by Gentoo. Currently Gentoo is the only distro which uses it, and it is not being considered for use, nor supported by any other distro. So I am not covering it's usage (though if opinion is that I do, I can add it).

share|improve this answer
    
OpenRC is kinda of an abstraction for SysVinit. It doesn't replace it, it adds to it. –  Spidey Dec 26 '13 at 15:55
    
Great writeup! Just a couple minor corrections: RHEL 6.x (and thus, CentOS 6.x and the rest of derivatives) uses upstart, like Ubuntu (though most of the services still use SysV scripts anyway). Also, I'd add that "chkconfig" (RH) and "update-rc.d" (Debian) are the "official" ways to add links to rc?.d directories. –  rsuarez Dec 26 '13 at 17:10
    
@rsuarez good point on the RHEL6 thing. Though not much seems to use it. Most of the system still runs via legacy SysVinit (17 upstart, 89 SysVinit on one of my RHEL6 systems). And chkconfig and update-rc.d are mentioned. See second paragraph under SysVinit :-) –  Patrick Dec 26 '13 at 17:28
    
@Patrick agree on #1; "oops!" on #2 :-) –  rsuarez Dec 26 '13 at 18:00
    
Thanks for the comprehensive answer, now I've got the big-picture. Currently I am using Debian (latest stable), here in German-speaking Europe it has the best recommendations, but maybe I'll give Redhat a try. –  Erdinc Ay Dec 26 '13 at 23:32
add comment

Different distributions use different mechanisms to manage services. The software to manage services is called init, after the traditional name for the very first process (with process ID 1) which is in charge of starting the others.

Debian uses the traditional SysVinit variant of init. Under this system, there is a collection of scripts in the directory /etc/init (this and other location may vary slightly between distributions that use SysVinit). These scripts are not invoked directly, but through symbolic links in directories /etc/rc?.d. It is the presence and the name of these symbolic links that determine when services are started. For more details, read the chapter on init in the Debian Reference.

Have a look in /etc/rc?.d to see what services are already present. The letter or digit before the dot is the runlevel; entries whose name starts with S are executed with the argument start when entering the runlevel, and entries whose name starts with K are executed when leaving the runlevel. The normal runlevel sequence is: S during boot (so /etc/rcS.d/S* are executed), then 2 (so /etc/rc2.d/S* are executed). At shutdown time, /etc/rc2.d/K* are executed, then the runlevel switches to 0 (or 6 for a reboot).

In a nutshell, if you want to create a startup script for a new service:

  • Write a shell script in /etc/init.d. This script must accept one argument which may be start, stop, force-reload, restart, or (optional) reload or status. The difference between reload and restart is that restart is equivalent to stop followed by start while reload reloads the configuration without stopping anything (if the service supports it); force-reload does reload if available and restart otherwise. See the existing files and Making scripts run at boot time with Debian for examples.
  • Run update-rc.d to create symbolic links to start and stop your service. Most services run in runlevels 2, 3, 4 and 5.

Note that to provide svn access, it may be easier to set up Apache and use the HTTP or HTTPS protocol. This has the side benefit of allowing quick repository browsing through a web browser.

share|improve this answer
add comment

From A traditional unix background there is nothing special about services they are just another process, with two exceptions: they don't need a terminal and they get started at boot. how they get started at boot depends on init (which could be sysv init, bsd init, upstart, systemd or something else; check your man page for init) and weather your are using a wrapper for the task or for the init configuration. There is nothing stopping you from running a service from a terminal, in fact it is common for testing purposes.

share|improve this answer
    
Thanks for the clear statement. –  Erdinc Ay Dec 26 '13 at 23:32
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.