a few niggly little linux questions

[Calum]

just wondering if anybody can rattle off an easy answer or a one liner (or more if you can be bothered!) to deal with the following concerns i have about linux right now:

1) i just started using xcdroast, which i really like, now the way i'm doing it is i'm turning mp3s into music CDs. i use xmms, with disk writer plugin to make wavs of the mp3s, then i put the wavs into a directory and use xcdroast to make a music CD out of the wav files in that directory. Now that directory used to be /home/cdimgs HOWEVER i have noticed that mandrake (9.0) continues to change the permissions of the directory to 711 no matter what i do. I keep changing it to 777 but it changes it back to 711 after 10 minutes or half an hour, i didn't pay attention how long it takes each time. So i am now using ~/cdimgs instead, but i want to use /home/cdimgs so that each user has access to the same folder to put their wavs into. What could be causing mandrake to do this and how would i change it (and hopefully learn how to deal with similar things in future) it seems to me like some script somewhere might be chmodding /home/* for security reasons.

2) on the laptop now, i have decided to set up a system where i multiboot six operating systems. FreeDOS, FreeBSD and four different linuces. Now the BSD and Linux OSs will all share a swap file and a home directory (not sure about FreeBSD actually, will burn that bridge when i get there) BUT i have an issue with graphical desktops. So far i have set up Red Hat with GNOME and windowmaker, and KDE with windowmaker, blackbox, XFce and iceWM. Now you know that each graphical desktop saves its config info in your home directory, in folders such as .kde and .xfce? well, what if i want to have more than one system running, oh let's say KDE, but i do not want them to have the same settings? I might want different theme settings, or different shortcuts on my desktop (like if i had gnutella and gaim installed on one system and not on another, i might want desktop shortcuts to them on only one KDE desktop). Can this be done? if so how? If possible i really need to know how to apply this idea to all the desktop environments i have, but if it is insurmountable then i can just use Windowmaker on FreeBSD, XFce on mandrake, GNOME on red hat, KDE on Lycoris et cetera.

3) related to the above really, what's the way to change the default runlevel from 5 to 3 or vice versa? which file needs editing? also, if i have xdm, gdm and kdm installed all on the same system, where can i specify which one i want to run (if any) when X starts? if i have multiple desktop environments installed as well, how do i specify which is the default? (for instance i have been on a computer with XFce and iceWM installed, but if you startx, you get iceWM, no questions asked). Also, how would i write a script to run when startx is executed? i don't mean how do i write the script, i mean how do i make sure that the script is run as well as (before?) XWindows when the user types 'startx'?

4) how do i allow a user to run a program that requires root priveleges? on red hat in particular i have noticed that some programs will run as a normal user, but will ask you for the root password, ('shutdown' is a good example of this), how do i set it up to allow a user, or all users to execute this command?

5) how do i configure GRUB? the man page seems to not tell me anything. how do i set the stuff up that i want for GRUB and then how do i install that info to the boot record?

6) I want to try out some networking. i want to install SAMBA and apache and so on and fiddle with it to try it out. I do have two computers, but only one has a network card. Both have a 56k modem, but what's the good of that? anyway, i don't want to fiddle with the desktop computer too much anyway, as it's the 'serious' machine, so that leaves me with one laptop, with all network hardware attached. Is there any way at all on this green earth that i can become familiar with networking using only one computer? This computer as i say will have a good number of Free operating systems on it and i just want to get to know something about networking and firewalling but really i only have one computer to do it with. Is there any way other than just reading the apache man pages? it'll never sink in that way.

Thanks in advance, folks, i look forward to hearing your thoughts on any of these things.

[ January 29, 2003: Message edited by: Calum: Member # 81 ]

[Master of Reality]

I bet all your problems could be solved with hours of reading manuals  
I've been awake too long to reliably answer those questions, but perhaps for the first one you should make the dir under /usr or /usr/local and make it 777 permissions, seems to work for me.

[Calum]

i know, MoR, the answers to these and every other question can usually be had by reading the F*$%

[Master of Reality]

did you check cron and at jobs to see if there was anything that does that?

[Calum]

nope! i'm a dumbass you see. having just printed the relevant articles off of mandrakeuser.org though, i will do just that this very evening.

[beltorak0]

1. stop using /home.  try /opt/cdimg.  then make a symlink.  I think M/9 is assuming that those perms are a mistake; as for what is doing it, i dunno.  I remember trying to do the same, and even though slackware never re-perm'd it, i couldn't access them.  I use /usr/local/music, but that's just my preference.

2.  edit "/etc/inittab".  look for the following line:
"id:5:initdefault:".  change that 5 to a 3.

3.  try this: for each wm and OS, make a .$wm.$OS directory to store your preferences.  Then, in ".profile", have it check to see what OS you are running, and create the neccessary symlinks for each "$.wm".

4.  (note: slackware specific) in /etc/inittab, the should be a line that looks like:
x1:4:wait:/etc/rc.d/rc.4
(your numbers will be "5" of course.)  That is the script that is executed when running that runlevel.  you can edit it, but if it is set up to check if the xdm's cousins are executable before executing them, then you can just turn off the executable bit in the xmd-cousin you don't want to use.  ie: my script fragment looks like this:

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so all i would have to do is "chmod a-x /usr/X11R6/bin/kdm" and gdm would become the default $xdm.  If i felt like punishing myself i could also "chmod a-x $samepath/gdm" and give xdm-proper a whirl.

3b.  again, solve it with symlinks.  The window manager start up routines are actually sh-scripts in the directory "/etc/X11/xinit", and are named "xinitrc.$wm".  "ln -s /path/xinitrc.$wm-of-yer-choice ~/.xinitrc" and startx will use that script upon loading X.  I have a script that lets me choose (but it prolly wouldn't work under runlevel 4 or 5, or whatever).  It's at the end of this post, so if you want to grab it, feel free.  You can always rename starx something else and name the script startx, but i just call it "x".

4.  

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under slackware: root (the partition of the root fs) is specified as /dev/hda5 ( (hd0,4) in bsd-speak i think).  My kernel resides on partition /dev/hda2 (which gets mounted under /boot).  The only things that are essential are the title and kernel lines.  and the root line if the kernel doesn't know it is on a different partition.  anything else is just options to the kernel.

now for the setup:

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you should see something like "found stage1 file... found stage2 file... setup complete".  if not try typing "help" into the grub prompt for information about how to get grub to search thru the partitions for it's own files.  i don't remember the command off hand.  also note: if you do not have the picture patch for grub installed, you will not get the splash screen to work.  i have not done it yet, so my slack.xpm is limp and worthless       .  I think that the grub that comes with M/9 has it applied.

last).  as for networking, i whish i could get experience.  i have a spare computer without a hard drive, and i haven't found the time to learn how to set it up as a thin client even.       (.  we could collaberate and set up a VPN, but that might be even more work.... let me know.  I have a few friends interested....

I hope this helps...

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[ January 29, 2003: Message edited by: beltorak ]

[ January 29, 2003: Message edited by: beltorak ]

[Calum]

beltorak, thank you very much for that!
i will begin assimilating that information right away! this machine already has red hat, mandrake and freeDOS on it, so i can use the red hat grub (in a lot of ways i do prefer red hat to mdk when it's running right) which i know does have that xpm patch because it shows me a little picture of a penguin at boot time.

As for me getting involved in a VPN, i would love to but i really think that since i know nothing about networking and since i have very little time right now that i will have to bow out for now. Remember me in future though...

and again, thanks.

[beltorak0]

yeah; none of my friends have any time to set up a VPN -- me included.  If i ever get serious about it I'll let ya know...

glad to be of service...

also, i just found out today, that if you already have grub set up on the system, you do not need to go thru the setup again.  Grub reads the "menu.lst" file right off the hard drive at each boot, so if you make a change in there for a working grub, it will take effect on the next boot.  very cool indeed.

well, take care!

[5amYan]

3. You can manually change the runlevel at command line as root by;
#/sbin/init n
where = an integer 0-9
0=halt
1=single user
2=??
3=??(some linux use this for multi user/network runlevel)
4=??
5=Usually multi user or network or in the case where those are in three this may be for x
6=reboot
7-9=unused in linux
Note: runlevels I think are from System V UNIX.  FreeBSD doesn't use runlevels. There is single and multiuser modes and that's it.  Nice and simple.

4. sudo >>>or better yet assign a group privs to exec what you want and add users you want to that group.

5.  As a note FBSD can be called in grub nearly the same way as windows.
 rootnoverify (hdx,xa) ## the a would specify whoch slice of the partition the BSD kernel is on.
 chainloader +1

6. I guess you could get vmware and run mutiple OS simultaneously.  Or maybe setup a faux network with honeyd for firewall implementation testing.  You can also connect via serial parallel or USB ports depending on what's available

[ February 17, 2003: Message edited by: 5amYan ]

[Calum]

thanks! top answers!