Date: Sun, 9 Jan 2000 02:41:07 +0100 (CET) From: Oliver Fromme <olli@dorifer.heim3.tu-clausthal.de> To: freebsd-questions@FreeBSD.ORG Subject: Re: Newbie has a lot of questions... Message-ID: <200001090141.CAA74135@dorifer.heim3.tu-clausthal.de> In-Reply-To: <857la6$hvm$1@atlantis.rz.tu-clausthal.de>
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John Indra <m4v3r1ck@bigfoot.com> wrote in list.freebsd-questions: > On Sat, Jan 08, 2000 at 02:05:57PM +0100, Oliver Fromme wrote: > [...] > Talking about Chuck... Anyone know where to download Chuck images? I > want to use them as my Enlightenment wallpaper ;) Someone else already recommended a web page with lots of images. If you want a reall big one, for high resolution printing or something like that, you might want to try this: http://www.fromme.com/t-shirt/ Originally, I made that picture for a bunch of T-shirts for some friends of mine. Scanned it from a CD cover and prepared it with Corel PhotoPaint... (no flames, please, but I don't like Gimp that much). > Anyway, to put it into thoughts; since the first time I used Linux, > I haven't really jumped into another runlevel beside of runlevel 3, > which I believe most Linux distros choose as the default multiuser mode > "runlevel". Well... to confess a little lie, if rebooting (runlevel 6) > and halting machine (runlevel 0) and single-user mode (runlevel 1) > must be called runlevels... then: yes, I have jumped into another > runlevel ;) Well, FreeBSD has those, too, but doesn't handle or call them in any special way. ;-) ``shutdown -h'' will halt the system. (On a PC, this hasn't much usefulness. On the Alpha, you return to the firmware console.) ``shutdown -r'' will reboot the system. > | The manpage can. :-) > > Ha3x... OK... I'll read it... later maybe ;) > It's not that I have something against csh, it's just... like I've > mentioned before, I'm a novice sysadmin. And my first UNIX resemblance > OS was Linux, which by default use bash. > That's why, I have been like "comparing" csh to bash... To be honest, I don't like csh (and derivatives) very much. But normally, you don't have to use csh anyway. When you use ``su -m'', you get yout normal user shell as root shell. And when you enter single-user mode, the system asks your for the shell, so you can choose /bin/sh, if you want (and when /usr ist mounted, you can then call any locally installed shell). > Hmm... since this issue have been brought up to conversation... Can > anyone please "open" my eyes... > Till now, I haven't understand, what's the security risk to login as > root from the console. I can't think of a real security risk. But using "su" has certain advantages: First of all, when multiple admins work on a box, you can see who is doing what, and in case of emergency (if something goes very wrong) you can ask the admin who was last wotking on that part of the system. But if you log in as root on the console, you're working "anonymously" without connection to a real login name -- then it's very difficult to track things down if necessary. Another advantage: Suppose you have used su and you're working in the root shell. If you now need to do something as normal user (e.g. checking your mail or whatever, which you should not do as root, obviously), you can simply type ``suspend'' in your root shell, and you're back at your user shell prompt. When you're done reading mail (or whatever), type ``fg'' and you're back in your root shell. Using these two commands, you can switch back and forth between user and root shell without losing any of their settings (variables, aliases, history etc.), which is very convenient. > | LKMs are old and obsolete. The directory exists solely for > | compatibility. The new kernel modules are called KLDs. > > Now... I don't see that being mentioned on the handbook and FAQ... or am > I missing an entry again? I'm not sure. Maybe the Handbook is not quite up-to-date on this issue. The problem is that a _lot_ of people are working on the actual code, but only very few seem to work on the docs. I'm a programmer, too, and I know very well that writing good docs can be more difficult and time-consuming than writing good code. FreeBSD is a volunteer project, and therefore what we have is what some volunteers were able and willing to provide. Maybe at some point in the future, when you have evolved to a FreeBSD expert, you are able to improve FreeBSD's docs and help the project to become even better. :) > So... what harm will strike me if I rm -rf /lkm? Probably no harm at all. I can't think of any reason why you would need that directory. It's a left-over from past days. > | kernel is not compressed by default. There is (or was) support > | for compressing it, but it has disadvantages (e.g. kernel > | symbols don't work anymore, so you can't debug it, and certain > | tools don't work anymore), and there aren't really any > | advantages. > > Hmmm... OK... > But just a newbie thought... Why don't FreeBSD compress /kernel anyway, > and have the bootstrap "uncompress" it when it try to load /kernel... > Then it will be the same as not compressing /kernel right? Not exactly. There are tools that read kernel symbols from the /kernel file (or whatever ``sysctl kern.bootfile'' says). Therefore that file must not be compressed, or those tools will fail. This affects tools like netstat and vmstat. It is really not worth the trouble, just to save a few 100 Kb on your harddisk. Nowadays, Gbytes of HD space cost only a few dollars. (With today's cheap IDE disks, 100 Kbyte are about 0.1 cents, that's $0.001. Even if you save 1 Mbyte, that's just $0.01...). However, the kernel _is_ compressed on the FreeBSD install floppies, for obvious reasons. But then again, you probably don't neet netstat, vmstat etc. during installation. > So... if I omit an options line... I will be missing an option or will > it fall to the defaulted configuration? This depends on the kind of option. > Take this as an example: > > options ATAPI_STATIC > > If I omit this entry from my kernel config file, what will my /kernel be? Your /kernel will not contain the static ATAPI code. When that code is needed, it will then be loaded from a KLD module. > Now... how do I make the /modules/*.ko? You don't need to make them, they're already there. There is usually no reason to recompile them, except when you update the whole system ("make world"). > Or I don't even have to bother to make them as FreeBSD developers have > kindly supplied those KLDs for me? ;) Yes, exactly. :-) > He3x... I'm sounding like I'm comparing FreeBSD to much to Linux ain't > I? ;) That's understandable, since you're coming from Linux and being familiar with it. > Sorry... cause FreeBSD is still brand new to me and I have to adapt... I'm sure that you will learn the differences very fast. > | If you have a complete source tree of the system installed > | under /usr/src, you can use a mechanism called "make world" > | to update, recompile and re-install the complete operating > | system. > > Whooaaa... cool!!! I can do that in FreeBSD??? Yes. That's one of the most fun parts of FreeBSD. :) > When I spotted the phrase "make world" my first impression was when I > make install as the final step in compiling kernel, that's the process > of "making world". The "world" is much more than just the kernel. It's everything in /bin, /sbin, /usr/bin, /usr/sbin, /usr/lib, /include and possibly a few other places that I forgot right now (and which are not that important). (In fact, a "make world" will not compile a new kernel; you'll have to do that separately.) Furthermore, there is a thing called "make release", which will produce the FTP release tree (the installation files that you can find on the official FreeBSD FTP servers) and even prepare CD-ROM images from which you can install (plus live filesystem CD-ROM). However, "make release" is for experts only and not for the average user. > | Use kldstat. > > OK... > I think this info got to be inserted to the Handbook... See my comment about the docs, above. Regards Oliver -- Oliver Fromme, Leibnizstr. 18/61, 38678 Clausthal, Germany (Info: finger userinfo:olli@dorifer.heim3.tu-clausthal.de) "In jedem Stück Kohle wartet ein Diamant auf seine Geburt" (Terry Pratchett) To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
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