This article describes how Linux boots. Who loads what, who starts which program, and what services do and act like.
The Linux Booting Process
About The Author
Eugenia Loli
Ex-programmer, ex-editor in chief at OSAlert.com, now a visual artist/filmmaker.
Follow me on Twitter @EugeniaLoli
every little bit helps you know . . .
Great article. Informative, descriptive, and explanitory. These are things that a merely 2-year linux user like myself was always interested in finding out but never knew where to go or what to look for.
Not all my hopes for this article were fulfilled, however, for i would have loved for the article to explain what, for example, all the basic redhat services are and why they start, so that i could finally turn off the ones i don’t really need.
Can anyone redirect me to a site that explains this element of a basic linux boot?
thanks in advance.
would have been something more like…
“The Redhat/SystemV based linux boot up process.”
Not to be a troll, but a lot of the “Linux” HOWTO documentations are based off of Redhat. Nothing wrong with that, but there are huge differences between SystemV & BSD style, and the focus of the article should be mentioned in the article title. This doesn’t apply to just this article, but many, MANY ones on the net. Sadly, including ones from TLDP. The author does mention that there are differences, but to effectively be a complete “Linux” (As it claims, and not just Redhat/SystemV) it should have descriptions of both. Many of us may already understand the differences, but for a new user this can become very misleading. It really makes people who are Solaris or *BSD administrators, shy away from using Linux in a corporate environment, when it seems that the documentation can’t keep it’s shit straight.
I’ve heard a lot about this *BSDgly on /. forums but it seemed pretty neat when I learned about it, so does any one wanna throw a quick diff or url out here?
Why everybody like to complain about something. It is just a basic description of the botting process of certain common configuration. Author is not tying to promote Linux over BSD. Even more, he states that BSD has a different mechanism he will not cover.
About article, is a little simple, I would expected something like booting process and optimizations or something.
If you want to know how the Debian boot process works: http://www.debian.org/doc/manuals/reference/ch-system.en.html#s-boo…
Hi
http://tldp.org/HOWTO/From-PowerUp-To-Bash-Prompt-HOWTO.html
Jess
Hello, I am the author
First: it *does* work like that with Debian. Except for service names, and specific lines in inittab, the boot process is the same, because it boots using the same programs. If you say it doesn't work, tell me how, I will update it.
Of course it's the Linux/SystemV booting process. I say that in the article. However, that covers about 90% of the unixy-like things you find, changing perhaps some folder names. How likely is it that you will be a OpenBSD admin and a newbie?
The problem with describing the BSD/Slackware boot process is that it's too amorphous. Basically you end in a boot script, and that's it. You boot however the script says you boot. You have to read it to find out.
That's what I don't like about it, BTW.
Yes, the article is light. Yes, a list of what each service does would be useful. However, you don't need it.
For example, to know what /etc/init.d/portmap does, on a RPM-based system, do this (on Debian it's a bit harder):
rpm -qf /etc/init.d/portmap
That will tell you what rpm put that service there.
Then, you can do
rpm -qi whateveritsnameis
for a brief description, and
rpm -qd whateveritis
for a list of the documentation files.
Booting optimizations: as long as you don't want to drop this scheme of booting: don't start whatever you don't need. There's not much else you can do.
There are some concepts floating that use parallel initialization of services which should be much faster, but they are also a lot harder to get right!
Finally: yes, I could have titled it “The linux booting process, as long as you use Red Hat 9, but most others have only minor differences, unless it's Slackware”, but somehow it didn't seem catchy enough.
BTW: my website would keep the comments along with the article, so if someone wants to repost his constructive comments there, it will be helpful for future readers.
Think about people reading it in a couple of years, finding it in google
I’ve always found it to be clunky and inelegant. The BSD init process is far nicer. It’s more intuitive (saying that word in a UNIX context always leaves me with mixed feelings
than sysv init, and therefore easier to modify. The documentation is also very excellent, which of course was always one of the great things about the BSDs.
People have said that Slackware has a BSD style init process, but when I finally went to see for myself, I learned that they have no idea what they were talking about. Oh well.
Runlevels are a long out moded concept, who actually uses anything besides full on or single when you forget the password. Quickinit or simpleinit in the util-linux pack launch everything in parallel with order based on the, ‘needs and provides’, concept is far more logical and easier to maintain. Distros need to evolve.
Yes, I am sure you can boot 45 seconds faster using simpleinit.
However, as long as no distro ships using it, what is the point in ignoring what exists? This article was not about how BSD init sucks, or how SysV init rules. To be absolutely honest, I don't give a damn about either.
It describes a thing that exists and is in use. If you use Linux, there is perhaps a 90% chance that you use this. Why not explain it? You know. Because you probably gonna run into it eventually?
At least some of them (jinit) will stop *every* network service when you bring network down. That's both usually unnecessary and slow.
minit is only meant for minimal systems.
runit is kinda cool, but hard to migrate to.
For quickinit all I found is a tarball, so I haven't studied it much (I have never tried it before)
Hello Troll,
Come on now, people can choose the OS that they want without needing to be flamed. I have been using FreeBSD since 4.6 and I am a very proud BSD user. Linux has its place for people and let it be, FreeBSD has a place as well, it just means that its place is on my desktop.
And as for startup, yes *BSD vs Linux on the same machine, FreeBSD is faster. The things I like, secure install, over 10,000 ports/packages, typically the latest packages (most of the time) and a regular release schedual, port_upgrade and the list goes on and on. The only 2-3 linux distroa that I can see that do something similar are:
Debian
Gentoo
Slackware
However, there isnt 1 of the 3 that that has all of the above. Let the chips fall where they may. People are free to use what ever OS they like/love, just let it be.
None,
if is true what you are speaking about, why Linux is more widely used than FreeBSD (in the server and enterprise usage i mean)?
if is true what you are speaking about, why Linux is more widely used than FreeBSD?
You could just as easilly use your poorly thought out argument as follows:
If Linux is so great, why are 90% of the worlds computers running Windows?
See? Pretty shoddy logic you’re using isn’t it?
“You could just as easilly use your poorly thought out argument as follows:
If Linux is so great, why are 90% of the worlds computers running Windows?
See? Pretty shoddy logic you’re using isn’t it?”
It’s shoddy because there’s nothing supporting it.
There are reasons why Windows has 90% marketshare.
There are reasons why people pick one over the other.
Some of the reasons are good, some bad. But as it stands it’s more trollish than anything because usually flamewars breakout, instead of reasoned debate, and live, let live attitudes.
You have an almost magical talent for stating the obvious. I applaud you sir or madam! Keep up the terrific work!
Thanks! I think?
Heheh. Don’t mind me, my sense of humor isn’t standard issue
a previous article here on the new netbsd booting process suggests that parallism might work as that bnooting process takes into acount dependencies of services (and non-dependencies more to the point). good design by netbsd.