Slackware FAQ, last revised: 14 May 1996 These are questions people ask me quite often. Hopefully now that they're answered here that won't be the case. :^) ----- Q: After installation, my ethernet, CDROM drive, and/or other hardware that I thought Linux supported doesn't work. Why? A: Probably because the kernel you're running doesn't contain the support. To fix the problem, you'll have to install a kernel that does. There might a suitable kernel in the /kernels directory on the CDROM, or you can compile a custom kernel for your machine. This isn't too difficult -- see the instructions below about compiling a new kernel. You can also try loading the device driver in the form of a kernel module. There are drivers for nearly all the hardware supported by Linux in the /modules directory on the CDROM, or in your /lib/modules directory if you've installed the modules.tgz package. Take a look at your /etc/rc.d/rc.modules file for examples of how to load these. ----- Q: Why can't Linux install on my EIDE hard drive? A: If you are using any of the various "Disk Manager" programs included with many EIDE drives, you won't be able to use the drive for Linux until you remove it. These programs are a hack to let DOS use more than 512MB, and render the drive unusable for any other OS. (Not just Linux... even OS/2 has trouble with these) The usual method for fixing the problem is to back up everything on the drive, wipe the boot record (FDISK /MBR), reformat, and then reinstall everything. NOTE: Some of the newer 1.3.x kernels claim to be able to work around some of these programs, so you might want to give one of those a try to see if they work. ----- Q: When I installed Slackware, the system could see my CD-ROM just fine. But, when I try to boot using LILO or the bootdisk the system doesn't find the CD-ROM drive anymore! How can I fix this? A: The problem is probably that you used a bootkernel disk with support for your CD-ROM drive, but didn't install a kernel with support. If you're ready to try compiling a kernel, you can easily solve this problem by compiling a custom kernel (see the section about compiling a Linux kernel) or, you can load the CDROM driver in the form of a kernel module. You can do this by editing the /etc/rc.d/rc.modules file to load the module for your CDROM drive the next time you boot. Here's the section of the file that loads CDROM drive modules: # These modules add CD-ROM drive support. Most of these drivers will probe # for the I/O address and IRQ of the drive automatically if the parameters # to configure them are omitted. Typically the I/O address will be specified # in hexadecimal, e.g.: cm206=0x300,11 # #/sbin/modprobe aztcd aztcd= #/sbin/modprobe cdu31a cdu31a_port= cdu31a_irq= #/sbin/modprobe cm206 cm206=, #/sbin/modprobe gscd gscd= #/sbin/modprobe mcd mcd=, #/sbin/modprobe mcdx mcdx=, #/sbin/modprobe optcd optcd= # Below, this last number is "1" for SoundBlaster Pro card, or "0" for a clone. #/sbin/modprobe sbpcd sbpcd=,1 #/sbin/modprobe sonycd535 sonycd535= #/sbin/modprobe sjcd sjcd= To use one of these, edit out the '#' in front of the line for your CDROM drive. If you know the I/O address and/or IRQ for your board, fill it in on the line. For example, you might change the sbpcd line to look like this if you've got a SoundBlaster CDROM at 0x300: /sbin/modprobe sbpcd sbpcd=0x300,1 If you need to access your CDROM drive so that you can get the modules package installed, use the same bootkernel disk you installed the system with to get into your machine. Use a command like this on the LILO prompt, but replace the root device name with the one you used on your machine: mount root=/dev/hda1 Once you're logged in, install the modules package: installpkg /cdrom/slakware/a*/modules.tgz ----- Q: Why isn't my Sony CDU-31/33a detected by Linux anymore? It used to work! A: From the source code: + * WARNING - All autoprobes have been removed from the driver. + * You MUST configure the CDU31A via a LILO config + * at boot time or in lilo.conf. I have the + * following in my lilo.conf: + * + * append="cdu31a=0x1f88,0,PAS" + * + * The first number is the I/O base address of the + * card. The second is the interrupt (0 means none). + * The third should be "PAS" if on a Pro-Audio + * spectrum, or nothing if on something else. You can also use this option with Loadlin: C:\LOADLIN\LOADLIN C:\LINUX\VMLINUZ root=/dev/hda1 cdu31a=0x1f88,0,PAS Or, on the bootkernel LILO: prompt. Examples: LILO: ramdisk cdu31a=0x1f88,0,PAS LILO: mount root=/dev/sda1 cdu31a=0x1f88,0,PAS ro ----- Q: I can't get the kernel to see a CDROM connected to a Soundblaster 16 IDE! A: First, be sure you're using the proper kernel -- the one needed in this case is the IDE/ATAPI CDROM type, not the SBPCD type. Then, if you still have problems, use the secondary IDE channel (IRQ 15 0x170), and make sure the drive is set as master (jumper in the back) and not as slave (a common default). ----- Q: I can't get the disks made by RAWRITE to boot! A: First, check that you're using the right size image. If you use an image meant for a 1.44 MB floppy on a 1.2 MB floppy (or vice-versa) you'll likely see the message "LI" and the boot process will hang. Another possibility is a BIOS problem -- a user has reported to me that RAWRITE fails on his machine unless he first does "dir a:" on an MS-DOS floppy. Apparently this is caused by the BIOS improperly initializing address 0000:0526 (number of sectors) to 11h instead of 12h. Using "dir" on the device fixes that value. The affected machine in this case was using "Mr. BIOS" from Unicore Software. ----- Q: I was able to install fine, but the installed system won't boot! A: Slackware uses stripped down kernels to do the actual installation -- in other words, the kernels don't have any more drivers than needed to control only the device needed to complete the installation. The kernels that are installed to the system are more full featured, with more ethernet, mouse, filesystem, and other drivers. Sometimes this can lead to hangs at boot time when the kernel misidentifies an piece of hardware that's unusual or at a non-standard port/IRQ. When this happens, you need to try a different kernel. First, use the bootdisk that worked during installation to get your system started. To do this, boot the disk and enter something like this at the LILO prompt: mount root=/dev/sda2 (if /dev/sda2 is your root Linux partition, otherwise use the appropriate device name for your system) Once you've got the system running, install or compile a different kernel. Try to include only the device drivers you need for your hardware. Instructions on compiling the kernel can be found in your kernel source directory (if you installed the kernel source, that is). The kernel source is usually found in /usr/src/linux. Briefly, this is the method for building a new kernel: cd /usr/src/linux make config (then answer the questions about what you need) make dep ; make clean ; make zImage If the zImage is successfully built, see an answer below which explains how to install it with LILO or Loadlin, or make a new bootdisk from it. Once you've done that, you might want to clean up /usr/src/linux by cd'ing into it and doing another 'make clean'. Good luck! If you can handle this, you're well on your way to becoming a Linux guru. ----- Q: Why do I get "network unreachable" under Slackware? A: There are a couple of possibilities. For most users, things work right out of the box. However, if you're running into this problem here are two workarounds you can try: 1. Reverse the broadcast and netmask arguments (and their variables) in the call to ifconfig in /etc/rc.d/rc.inet1. Make sure you are not trying to route your own IP address - you shouldn't have to. 2. Make sure /etc/networks is properly configured. 3. You may want to try the 'netconfig' script (in the package netcfg.tgz). It's not perfect, but does a pretty good job. 4. Make sure the kernel you're using supports your hardware. Most of the kernels provided with Slackware include a /boot/config.in file where you can look up the compilation options. ----- Q: Why the $%#@! isn't my UltraStor SCSI detected? It works under DOS! A: Set the I/O address to 0x340 instead to 0x330. For any hardware that doesn't work, a good rule is to try playing around with the IRQ and I/O settings on it to see what happens. If your system is up and running and you're having problems with a CD-ROM or tape or something like this, you can always look around for the driver source in /usr/src/linux/drivers... really, it won't bite! Often, the source contains important documentation, such as the default IRQ settings for that type of device, and the major number for the entry in /dev. Also, try other bootkernels and see if that helps. ----- Q: If the setup menus for NFS installation don't work, how can I setup the network manually before starting setup? A: Once your Linux machine is listed in the hosts /etc/exports (if the whole network is not already), you might need to do these things before running setup. This is usually only needed if the NFS server is on a different subnet than your Linux machine: # Setup the loopback device: ifconfig lo 127.0.0.1 route add -net 127.0.0.0 # Setup the network: ifconfig eth0 1.2.3.4 # 1.2.3.4 is the ip number of my machine. route add -net 1.2.3.0 route add default gw 1.2.3.1 # in this example, the ip address of our NFS # server is 1.2.31.4 and belongs to a different # network. ----- Q: My IBM Thinkpad won't load the rootdisk into a ramdisk correctly, so I can't install Linux. What can I do? A: The disk-changed sensor on some Thinkpads works a little differently. This can be worked around -- just specify "floppy=thinkpad" when booting: boot: ramdisk floppy=thinkpad ... on the bootdisk's LILO prompt. ----- Q: My large (> 1/2 gig) IDE drive reports more than 16 heads, and as a result Linux won't install on it. What can I do? A: See the file /docs/mini/Large-IDE for instructions on how to make it work. (Thanks to Bob DiMarco for forwarding this to me, and Patrick LoPresti for compiling the information in the first place) Note that newer kernels (> 1.1.40) will do this translation for you automatically, and thus make the workaround unnecessary. ----- Q: How do I make a Slackware bootkernel disk with this new kernel I made? A: OK, well you grab an existing one like the "bare.gz", put it on a floppy, and do this: mount /dev/fd0 /mnt (this mounts it) cat zImage > /mnt/vmlinuz (put the new kernel in place) rdev -R /mnt/vmlinuz 0 (mount read-write) rdev /mnt/vmlinuz /dev/fd0H1440 (use that drive, or /dev/fd0h1200) rdev -r /mnt/vmlinuz 1440 (set the ramdisk size, or use 1200 with 1.2 meg) lilo -r /mnt (reinstall lilo) umount /mnt (that's it! you're done! :^) If you want it to stop and give the message to switch disks, you'll need the ramdisk.c patch in /pub/linux/slackware/kernels on ftp.cdrom.com. I have no idea if this will still patch into the newest kernels. Otherwise, you don't really need it if you're brave enough to just switch the new disk in as soon as you see the "Uncompressing Linux..." message. It's always worked for me. ----- Q: My backspace is acting strangely under X? How can I fix it? A: Well, I've never noticed a real problem, but I occasionally hear about this. You might want to try adding this to your .Xmodmap in /usr/X11/lib/X11/xinit or $HOME: keycode 22 = BackSpace ----- Q: I just built a new kernel. Now how to I go about replacing my existing kernel with this new zImage file? A: First, you must prepare the new kernel. If you're using UMSDOS, you'll want your system to boot read-write. Otherwise, you'll want it to boot read-only so your filesystems can be safely checked. So, do this: For UMSDOS: rdev -R zImage 0 For any other filesystem type: rdev -R zImage 1 Then, you'll need to set the root partition. For example, if your root Linux partition is /dev/hda2, you'd do this: rdev zImage /dev/hda2 Then, you can set a video mode if you like. As an example, this sets normal 80x25 console mode: rdev -v zImage -1 Other modes include: -3 = Prompt, -2 = Extended VGA. You might need to remove a line in your /etc/lilo.conf that forces normal video if you use LILO and wish to try an extended video mode. Next, you need to install the kernel. If you boot from a floppy disk, you can simply stick a formatted floppy into your drive and write the zImage to it like this: cat zImage > /dev/fd0 If you use lilo, you should copy the zImage to where your lilo.conf expects it to be and then reinstall lilo. This should work if you used Slackware's liloconfig script to set up LILO. (this is the script setup uses) cp zImage /vmlinuz ; lilo You may wish to back up your existing /vmlinuz first. If you use Loadlin, copy the kernel to your DOS partition where Loadlin can see it (if you use UMSDOS, you won't need to do this). Then, start Linux from DOS like this: c:\loadlin\loadlin.exe c:\linux\vmlinuz root=/dev/hda2 That should do it. ----- Q: Why can't I cut and paste from elvis (vi) in an xterm? A: Later versions of elvis use the mouse for cursor positioning instead. If you want to cut and paste, hold the left shift key down while you use the mouse. ----- Q: Why doesn't my bus mouse work? The kernel, selection, the X server and test-mouse all say "no such device." A: The kernels distributed with Slackware don't have the drivers for busmice compiled in. Last time I tried to include all of them there were horrible driver conflicts -- better to leave them out if they can't coexist. Obviously, it's not feasible for me to provide versions of every precompiled kernel for each type of busmouse. I only have a 386. ;^) The solution is to get the kernel sources, configure the kernel to support the your type of mouse and no other mouse devices, and rebuild it. Documentation on how to do this is included in the kernel source, i.e. the kernel.tgz package found in the D series. You will also need at least the gcc.tgz, include.tgz, libc.tgz, and binutils.tgz packages from the D series to rebuild the kernel. ----- Q: I see my SoundBlaster/Panasonic CD-ROM detected at boot, but I can't install from it or mount it. What's going on? A. Try setting to drive's ID to 0. This is expected by the install disks. There should be a jumper on the back of the drive that selects this -- just move it to the leftmost position. ----- Q: I'm using UMSDOS and would like to use the same swapspace under Windows and Linux. Can this be done? A: If you want to share a Linux-UMSDOS swapfile with MS-Windows, you can do the following: 1. Create PERMANENT(!) swap file in MS-Windows with size NNNN kbytes. 2. In /etc/rc.d/rc.local add the following lines: rm -f /DOS/windows/spart.par <--- Needed in order to suppress Windows complain on next start! mkswap /DOS/386spart.par NNNN sync swapon /DOS/386spart.par 3.In /etc/rc.d/rc.0 add "swapoff" for this file. ----- Q: What's the password for root on the install disk? A: There isn't one. If you're asked for one, it usually means that you don't have enough memory to install. To help work around this, look in your CMOS settings and make sure you don't have any ROM shadowing enabled. ROM shadowing wastes memory and won't improve the performance of Linux. Also, make sure you're using the smallest bootkernel disk you can. For example, you don't need to use "scsinet" if you're not installing to a SCSI drive via NFS. Use something small -- the "bare" disk if you can get away with it. Some people mistakenly think they need to use a bootkernel disk with network drivers if they plan to use networking after installation. Not so! The drivers on the bootkernel disk have no impact on what you can use *after* installation -- in almost all cases you won't be running the same kernel on your installed system as you used to install it. ----- Q: How can I install and remove software now that the Slackware Linux distribution is installed on my machine? A: To remove packages, type "pkgtool" and follow the prompts. Pkgtool will also allow you to add packages that are in the current directory. The preferred way to install software is with the "setup" script. When you do your initial installation, setup puts a copy of itself in your /sbin for future use. You can also add software to your machine using the boot/install disk, if you really want to. When adding software to a running system via NFS, it is preferable to mount the partition yourself and then use the 'install from a mounted directory' feature of setup. There are also command line utilities that allow you to create, install, and remove packages. For these, you should refer to the manpages: installpkg(8), removepkg(8), makepkg(8), explodepkg(8). A simple example of how you would install a package with installpkg: installpkg package.tgz ----- Q. How do I know what files setup/pkgtool/installpkg is putting where ? A. Look around in /var/adm/packages. Similarly, you can find installation scripts for each package in /var/adm/scripts. ----- Q: I set my partitions to "Linux native" but Slackware still won't detect them! What can I do? A: This problem is rare and I still don't know what causes it. [ Note that this is not the same problem that usually affects the IBM PS/1, Thinkpad, and similar machines that do not detect the harddrive. If you've got one of these machines, and fdisk is giving you problems, your answer is still ahead :^) ] Here's a workaround you can use to install anyway: 1. Start tty12 or tty144 using one of the bootkernel disks. 2. Make and format partitions for Linux. 3. Mount the target partitions under /mnt. 4. Type "setup -target_mounted" 5. Follow the rest of the instructions to install. 6. Type "vi /mnt/etc/fstab" and enter an appropriate fstab. As an example, here's what mine contains: /dev/hdb2 swap swap defaults /dev/hda2 / ext2 defaults /dev/hda3 /usr xiafs defaults /dev/hda1 /dos msdos defaults /dev/hdb1 /os2 msdos defaults none /proc proc defaults To give you some more info about this file, the first field is the partition to be mounted, the second is where it should be mounted, the third is the filesystem type, and the last field is the options to use. Unless you're a Linux wizard, just set this to "defaults". Other things to remember about this file: - Make sure that you list the root partition before any other partitions that are mounted beneath it. - Add the /proc line, or "ps", "w", etc, won't work. - It's a good idea to put a blank line at the end of the file, as I've had reports that partitions listed on the last line might not be mounted. 7. Once you've made and saved this file you can reboot with ctrl-alt-delete. ----- Q: I have a (PS/1 || Valuepoint || Thinkpad), and can't install because fdisk can't see my hard drive. How can I get around this? A: You'll need to enter your drive parameters at the bootkernel prompt. You can even specify the geometry for your second IDE drive by supplying a second hd= parameter right after the first one. When you boot the bootkernel disk, you'll see more information about the format used to pass your drive parameters to the kernel at the LILO prompt and allow your drive to be recognized. You'll have to edit your lilo.conf file to add a similar hd= flag if you want LILO to work. Add this as the TOP line in the file: append="hd=cyl,hds,secs" Where "cyl", "hds", and "secs" are the number of cylinders, sectors, and heads on the drive. If you have two IDE drives, specify both drives (like this): append="hd=967,13,31 hd=944,14,40" ----- Q: Why do my /etc/issue and /etc/motd keep resetting themselves at boot time? A: The /etc/rc.d/rc.S resets them out every time you boot after figuring out which kernel you're running -- otherwise the kernel version printed at login might not stay current. If you want to write your own /etc/issue and /etc/motd, you need to comment out that part of /etc/rc.d/rc.S. ----- Q: Emacs dumps core, complains of a missing library, or lacks X11 support! Why? A: The GNU Emacs series includes your choice of a version with X11 support, or one without. Make sure you have the right binary for your machine. The binary supporting X11 is installed as part of a package on the first disk that you'll need to install whether you want X11 support or not. If you DO NOT want X11 support, install the package 'emac_nox.tgz' on the last disk of the Emacs series. If you just install all of the disks, you don't get X11 support. It had to be one way or the other, so if you're not paying attention when you install at least this way it will run no matter what. ----- Q: Why do my compiles sometimes die with 'signal 11: internal compiler error'? A: This indicates a hardware problem in about 99% of the cases. It can usually be fixed by increasing the number of wait states in the CMOS settings. It can almost always be fixed by turning off the RAM cache, but this should be your last resort since it will cause a noticeable slowdown. ----- Q: How can I change (or get rid of) the color ls? A: Read the man page, and check out the file /etc/DIR_COLORS. You can configure the colors any way you like, or shut them off entirely. Also, you can copy /etc/DIR_COLORS into your home directory as '.dir_colors' to override the global defaults on a user by user basis. ----- Q: I start X with "openwin" and it works OK, but I can't switch virtual consoles. Why? A: On a Linux text screen, you switch virtual consoles with Alt-F1 through Alt-F8. Under XFree-86, you must use Ctrl-Alt-F1 through Ctrl-Alt-F8. Another useful 'secret' key combination is RightShift-PgUp/PgDown for scrollback. (a random amount ranging from none to a few pages, depending on the state of your video text buffer memory) ----- Q: Why can't I use the new ghostscript with X? A: Make sure you have gs_x11.tgz from disk XAP1 installed. ----- Q: I can't get anything to work at all! What's the deal? A: If you seem to suffer catastrophic failure (!), then check the file FILE_LIST on ftp.cdrom.com in /pub/linux/slackware against the contents of your disks and make sure you're not missing any files. Also, I've noticed that most of the reports of kernel panics and system hangs have come from people with 4MB. If you're running into these types of problems I'd suggest forking over the $$$ for 4 more meg. I have 8 MB of RAM and never have crashes. (well, only when I really push my luck) If you don't want to do that, then go through your /etc/rc.d/rc.* files and get rid of any daemons you don't use, like crond, lpd, or selection. If you've got 4 MB and you're getting 'virtual memory exceeded in new' warnings, make sure you set up and activate a swap partition before running setup. If you're really hard up on memory, you can boot a rootdisk using 'editroot' instead of one of the usual boot kernels. This will mount the floppy in the root drive, and you'll have to install from the other drive or from the hard drive. You will also not be able to create any kind of boot disk, so you'll have to install LILO and take your chances. I only suggest using this approach if a swapfile will not work. ----- Q: How do I make a bootkernel disk that uses a custom kernel? A: Look in the ./kernels subdirectory. You'll find complete instructions on how to make them in there. ----- Also - at ftp.gwdg.de:/pub/linux/install-mount/slack-info are some more networking hints. In addition, the LDP people have put out an excellent set of manuals that I may include in a future Slackware release. These are available on sunsite.unc.edu in /pub/Linux/docs/LDP. --- Patrick Volkerding volkerdi@mhd1.moorhead.msus.edu volkerdi@ftp.cdrom.com