Linux frequently asked questions

On this page:

GNOME locks up when I try to log in or when I start X!
What is the currently supported version of linux?
How do I use my CD-writer?
How do I start the network manually after booting?
How can I use the SCS dialups via modem under Linux?
I can't run <some binary program>.
My machine crashed and now it's asking for a password because it needs to fsck a filesystem, or it's giving me the error: "/etc/shadow: root password garbled"
I want to run [newer/another distribution of] Linux. Can I have facilities support?
How can I arrange or add items to LILO?
Vmware stopped working! How can I fix it?
The linux console is garbled when I exit X, or the monitor just turns off after I exit X.
How can I install/use my own perl packages?
Local depot collections for laptops or offsite machines
kauthd does not work with RedHat 9
Other Linux questions

GNOME locks up when I try to log in or when I start X!

If you home directory is /afs/cs.cmu.edu/user/username and you use the GNOME desktop environment, when you log in and start X, sometimes GNOME will hang, and never start up a window manager or hand over control to you. This can happen when certain files get corrupted in your AFS home directory. This corruption isn't your fault, it can happen during regularly scheduled maintanance to AFS, or when your AFS tokens expire while you are running GNOME. The corrupted files are:

~/.gconf/%gconf-xml-backend.lock/ior
~/.gconfd/lock/ior

The only way to fix the files themselves is for an AFS admin to run a tool to repair your volume. However, you can move the files out of the way so you can log on again and get back to work. Since the directory entries are damaged, you have to move the directories that contain the 'ior' file out of the way. I suggest running:

$ mv ~/.gconf/%gconf-xml-backend.lock  ~/.gconf/%gconf-xml-backend.lock.old
$ mv ~/.gconfd/lock ~/.gconfd/lock.old

Now you should be able to log in. Notify the helpdesk that there is a problem, and once they've fixed it, you can safely delete the aformentioned .old directories. Don't worry about losing any data, that directory doesn't hold any important data, just a temporary socket file created and used by GNOME each time you start a new login session.

What is the currently supported version of linux?

The latest release that SCS supports is Fedora Core 5.0. If you would like to upgrade your computer to a newer supported OS, please read these guidelines .

How do I use my CD-writer?

See the Linux CD writing howto .

How do I start the network manually after booting?

To manually start the network, you can run the following command as root:

   /etc/sysconfig/network-scripts/ifup eth0

How can I use the SCS dialups via modem under Linux?

See the Using a modem under Linux howto .

I can't run <some binary program>.

There are several reasons why a binary will not run.

First, check whether you are executing it correctly, check man pages, etc.
If you are sure your are running it correctly, it's just not finding the file, make sure that the file you think you are running is not actually a symlink to some other file, which doesn't exists or is in AFS.
If the file is in AFS, make sure your network connection is working and see our instructions on troubleshooting AFS problems for additional troubleshooting information.
If none of these solutions work, you should email help@cs.cmu.edu.

My machine crashed and now it's asking for a password because it needs to fsck a filesystem, or it's giving me the error: "/etc/shadow: root password garbled"

You may see an error about the "root password is garbled". This is only because the program trying to give you a shell (sulogin ) doesn't understand the format of the password files that our login uses. You can often just hit return at the prompt, and it'll give you a shell. If it doesn't, you'll need a root password.
If you don't know the root password of your machine, this can be a problem. After this is resolved, make sure that you, or the administrator of your machine, set the root password to something that you know.
If neither you nor the administrator of your machine know the root password, there are still some options you can follow before calling facilities. Linux uses LILO to boot, and so you can trick LILO into giving you a shell. Note: this is an security problem with LILO, it is why linux is inherently insecure from the console.
First, write down the device that needs to be fscked. At the lilo prompt, type in the option to start linux, followed by init=/bin/sh . For example, when I boot, I would type:

LILO: linux init=/bin/sh

This will bring you to a shell. Type /sbin/fsck <devicename> ,where <devicename> is the device that you wrote down earlier. You may need to use /sbin/fsck.ext2 if it doesn't know what kind of filesystem it is.

I want to run [newer/another distribution of] Linux. Can I have facilities support?

Unfortunately, we cannot support every possible distribution of linux, since they all change constantly. We can't let people beta test anything on a stable system, unless they want to lose facilities support. If you have questions, feel free to email help@cs.cmu.edu .

Vmware stopped working! How can I fix it?

If you are currently running vmware installed by facilities (the vmware binary is at /usr/local/bin/vmware) or via RPM (/usr/bin/vmware), the most likey culprit is that there was a new kernel released, and the kernel modules necessary for vmware need to be rebuilt. This isn't done automatically, so run /usr/local/bin/vmware-setup or /usr/bin/vmware-config.pl, which will ask you several questions about your configuration. The default answer should work in most cases, contact help@cs.cmu.edu if you have any problems.
If the kernel modules are correctly loading (check /sbin/lsmod for modules like vmmon and vmnet), then it could be that the vmware services haven't been started, or have for some reason failed. Try restarting them with the command: /etc/rc.d/init.d/vmware restart.
You might see an error complaining that your vmware setup is not configured. This is because the vmware-setup failed at some point in the past. Try running vmware-setup again, or removing /etc/vmware/not_configured.
CMU SCS currently only supports version 2 of vmware out of /usr/local. If you want to run a later version on i386_rh71, you'll have to purchase an individual copy and have a VMware RPM installed.

How can I arrange or add items to LILO?

For i386_rh60 and i386_rh71:
You can edit the /etc/lilo.conf file to add entries. You'll notice that there are several entries. There's the current kernel, labeled 'linux', there's the default kernel, labeled 'default', there's a 'generic' kernel, a 'lkg' (last known good) kernel, a 'redhat' kernel, and possibly an entry for any other operating systems you might have. These entries are automatically regenerated.
For i386_linux3:
A facilitized machine has a unique way of handling the linux loader's configuration. Normally, one would edit /etc/lilo.conf, but on our machines, you should edit the files in /boot. /boot/lilo.conf.head is all the information at the beginning of the lilo.conf file, such as append statements and disk information. /boot/lilo.conf.tail is what would occur after the default entry for linux, such as an entry to boot windows. the process /usr/local/sbin/kernelmgr takes these two files and builds the /etc/lilo.conf, and then runs lilo. It dynamically builds the entry for the facilities kernel, so you don't need to enter that.

If you want to know more about the options you can put in your /boot/lilo.conf.head file, check out the LILO home page and the lilo and lilo.conf man pages.

The linux console is garbled when I exit X, or the monitor just turns off after I exit X.

If you are using a i386_rh60 machine with a 2.2.19 or greater kernel ,then the problem is probably that the kernel doesn't have framebuffer support. For example, if you have a card that has the Permidia 2 chipset, this will happen. To turn off the linux framebuffer, put the following into your /etc/lilo.conf :

append="video=vga16:off"