Retiring, March 2020 - sorry, you have missed our final public course.
The Coronavirus situation has lead us to suspend public training - which was on the cards anyway, with no plans to resume
Please ask about private 'maintenance' training for Python, Tcl, Perl, PHP, Lua, etc
Happily continuing private consultancy / programming work
What Linux run level am I in?
Linux / Unix systems have a "run level" that they're in ...
0 - halted
1 - single user
2 - multiuser (client)
3 - full multiuser
5 - full multiuser with X windows running
6 - reboot
How do I find out what run level a system is in at the moment?
- a question asked on today's Java course (OK - it was over lunch and we were
off topic ...)
1. The runlevel
command tells you what run level you are in
2. The who -r
command also tells you the run level, together with some other information.
Here's a machine which is in full multiuser mode, running as a server:
[trainee@melksham ~]$ /sbin/runlevel
[trainee@melksham ~]$ who -r
run-level 3 2009-05-15 09:28 last=S
And here's one which is in full multiuser mode and has the windows system running too ...
[trainee@easterton ~]$ /sbin/runlevel
[trainee@easterton ~]$ who -r
run-level 5 2009-05-15 15:04 last=S
1. The runlevel
command is intended for administrators only, so is in the sbin
directory which is not on the normal user's path. However, the command is purely information so is available to all users who know where to find it.
2. The default run level of a system can be changed by updating the /etc/inittab
file ... the line
will bring the system up into run state 5 on startup / reboot. Change the 5 to a 3 if you want the machine to start / reboot into run state 3
3. It is strongly recommended that you do not run your web servers in run state 5 ... I have had instances on a course where delegates have complained about a slow server, and they have been amazed when I have walked up to a 'spare' machine, moved the mouse around, and asked if the performance has improved. They have been even more amazed to be able to confirm that it HAS made a difference. What had happened? The system was running a screen saver in X Windows ... and it was eating up all the cpu resource in keeping an "atlantis" display of 3D whales and sharks swimming around the screen. Moving the mouse cancelled the screen saver ... and released the resources back to the server
4. Rather obviously, runlevel
cannot report that a machine is in run state 0! (written 2009-05-15)
Associated topics are indexed as below, or enter http://melksh.am/nnnn for individual articlesA164 - Web Application Deployment - Services and Regular Jobs 
Starting MySQL. ERROR! The server quit without updating PID file - how we fixed it. - (2015-05-06) 
Managing daemons from a terminal session - (2012-07-01) 
The Kernel, Shells and Daemons. Greek Gods in computing - (2012-07-01) 
On time - (2011-01-23) 
What are .pid files? - (2010-10-23) 
Using the internet to remotely check for power failure at home (PHP) - (2009-04-29) 
daemons - what is running on my Linux server? - (2008-11-23) 
Dialects of English and Unix - (2008-08-21) 
memcached - overview, installation, example of use in PHP - (2008-08-02) 
Apache httpd, MySQL, PHP - installation procedure - (2008-08-01) 
FTP server on Fedora Linux - (2008-07-06) 
Changing a screen saver from a web page (PHP, Perl, OSX) - (2008-05-06) 
Automatic startup and shutdown of Tomcat - (2008-02-24) 
Linux run states, shell special commands, and directory structures - (2007-08-03) 
Linux / Unix - process priority and nice - (2007-01-10) 
Browser -> httpd -> Tomcat -> MySQL. Restarting. - (2006-10-28) 
Repeating tasks with crontab - (2005-12-27)
Some other Articles
An FAQ on the Apache httpd and Apache Tomcat web servers, and on using them togetherAbstract Classes - JavaChoosing the right version of Java and TomcatServlet life cycle, and Java Servlet variable scopeWhat Linux run level am I in?You cannot please all of the people all of the timePatterns in numbers - room occupancyOffers that I can refuseMelksham Candidates for Wiltshire Unitary ElectionPreventing forum spam - checks at sign up
4759 posts, page by page
Link to page ... 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96 at 50 posts per page
This is a page archived from The Horse's Mouth at
the diary and writings of Graham Ellis.
Every attempt was made to provide current information at the time the
page was written, but things do move forward in our business - new software
releases, price changes, new techniques. Please check back via
our main site for current courses,
prices, versions, etc - any mention of a price in "The Horse's Mouth"
cannot be taken as an offer to supply at that price.
Link to Ezine home page (for reading).
Link to Blogging home page (to add comments).