Best of Technical Support

Our experts answer your technical questions.
Interlace Mode

How do I take my monitor out of interlaced mode? I run it in non-interlaced mode in Windows 95, so I know it can run non-interlaced. I use the FVWM window manager. Thanks.

—Cliff Slackware 2.3

In order to change the mode in which X will be running, you need to change the XF86config file, generally located in the /etc/X11 directory. This file contains important information about your X server, such as the horizontal/vertical frequencies supported by your monitor. Editing this file by hand can be tricky, so I suggest you:

  1. Back up your running XF86config. (Do a find / -name XF86config to discover the correct location.)

  2. Run XF86config and change the desired features. Be very careful with the horizontal/vertical frequencies.

  3. Type startx at the prompt.

—Mario de Mello Bittencourt Neto

Stuck with Multi-serial Port Troubles

I bought an HP NetServer Pro (Pentium Pro) to run a multi-serial port (DigiBoard Xem 16 RS232 ports). I loaded in the 2.0.30 kernel sources from InfoMagic and recompiled the kernel to recognize the DigiBoard. I used a boot disk to boot-up Linux, but it didn't work. Each time, it hangs, and the error message returned is “vfs: kernel panic... etc.”

The original kernel on the boot disk works, but any recompilation of the kernel causes that error message. The DigiBoard module is loaded properly before the error appears.

I need to set the machine up urgently, and yet I'm stuck. I need help. Thank you.

—Weng-Yue Boey InfoMagic 2.0.30

Unfortunately, what you've described seems to be a hardware problem (bad cache, bad memory). You say that you can run any precompiled kernel, but if you try compiling yours (or any other huge program), you end up with a “got signal 11...” message.

I would suggest turning off the cache or removing some of the memory, then try compiling once more.

—Mario de Mello Bittencourt Neto

Firewall Troubles

I am setting up a firewall and masquerade at my office to service approximately fifty workstations. The masquerade will be used to allow multiple users to access the Internet with a private IP addressing scheme (\8), and the firewalling is for added security. I have successfully implemented masquerading in both a test and production environment; I have been successful with the firewall only in a test environment.

The problem in the test environment is when I change to the /sbin/init.d directory and attempt to execute firewall list, I get a “command not found” error. The firewall script is present in that directory. firewall start and firewall stop also will not execute.

Any suggestions on where to go next would be appreciated. Thanks,

—Doug Ford S.u.S.E. 5.0

It sounds like your current directory isn't included in your PATH. You can either set your PATH to include the current directory (generally a bad idea for root) or just prepend the command you want to run with ./, for example, ./firewall stop.

—Mark Bishop

Adding an Ethernet Driver to the Kernel

My Ethernet card was installed improperly. How do I add a new Ethernet driver into the kernel? I mean, how do I recompile the kernel to include the new driver?

—John Liu Slackware 2.0.29

As root, go into /usr/src/linux, run make menuconfig and when you're done, make zImage. The new kernel is then in /usr/src/linux/arch/i386/boot/. Put it somewhere else, such as the / directory, preferably with a new name, then configure and run LILO. (You should keep your old kernel in lilo.cfg in case the new one has problems.) Reboot.

—Ralf W. Stephan

Editing motd and issue

How do I edit the motd and issue files? Do I need to be in single-user mode? How do I get into single-user mode?

—Scott Slackware

Edit the file /etc/issue or /etc/motd with your favorite editor. No, you don't need to be in single-user mode.

—Mark Bishop