Next: 2.5.2 Hardware problems Up: 2.5 Running Into Trouble Previous: 2.5 Running Into Trouble

## 2.5.1 Problems with booting the installation media

When attempting to boot the installation media for the first time, you may encounter a number of problems. These are listed below. Note that the following problems are not related to booting your newly-installed Linux system. See Section 2.5.4 for information on these kinds of pitfalls.

- Floppy or media error when attempting to boot.

  The most popular cause for this kind of problem is a corrupt boot floppy. Either the floppy is physically damaged, in which case you should re-create the disk with a brand new floppy, or the data on the floppy is bad, in which case you should verify that you downloaded and transferred the data to the floppy correctly. In many cases, simply re-creating the boot floppy will solve your problems. Retrace your steps and try again.

  If you received your boot floppy from a mail order vendor or some other distributor, instead of downloading and creating it yourself, contact the distributor and ask for a new boot floppy---but only after verifying that this is indeed the problem.

- System ``hangs'' during boot or after booting.

  After the installation media boots, you will see a number of messages from the kernel itself, indicating which devices were detected and configured. After this, you will usually be presented with a login prompt, allowing you to proceed with installation (some distributions instead drop you right into an installation program of some kind). The system may appear to ``hang'' during several of these steps. During all of these steps, be patient; loading software from floppy is very slow. In many cases, the system has not hung at all, but is merely taking a long time. Verify that there is no drive or system activity for at least several minutes before assuming that the system is hung.

  1. After booting from the `LILO` prompt, the system must load the kernel image from floppy. This may take several seconds; you will know that things are going well if the floppy drive light is still on.

  2. While the kernel boots, SCSI devices must be probed for. If you do not have any SCSI devices installed, the system will ``hang'' for up to 15 seconds while the SCSI probe continues; this usually occurs after the line

     `lp_init: lp1 exists (0), using polling driver`

     appears on your screen.

  3. After the kernel is finished booting, control is transferred to the system bootup files on the floppy. Finally, you will be presented with a login prompt, or be dropped into an installation program. If you are presented with a login prompt such as

     `Linux login:`

     you should then login (usually as `root` or `install`---this varies with each distribution). After entering the username, the system may pause for 20 seconds or more while the installation program or shell is being loaded from floppy. Again, the floppy drive light should be on. Don't assume that the system is hung.

  Any of the above items may be the source of your problem. However, it is possible that the system actually may ``hang'' while booting, which can be due to several causes. First of all, you may not have enough available RAM to boot the installation media. (See the following item for information on disabling the ramdisk to free up memory.)

  The cause of many system hangs is hardware incompatibility. Section 1.8 in the last chapter presented an overview of supported hardware under Linux. Even if your hardware is supported, you may run into problems with incompatible hardware configurations which are causing the system to hang. See Section 2.5.2, below, for a discussion of hardware incompatibilities.

- System reports out of memory errors while attempting to boot or install the software.

  This item deals with the amount of RAM that you have available. On systems with 4 megabytes of RAM or less, you may run into trouble booting the installation media or installing the software itself. This is because many distributions use a ``ramdisk'', which is a filesystem loaded directly into RAM, for operations while using the installation media. The entire image of the installation boot floppy, for example, may be loaded into a ramdisk, which may require more than a megabyte of RAM.

  The solution to this problem is to disable the ramdisk option when booting the install media. Each release has a different procedure for doing this; on the SLS release, for example, you type ```floppy`'' at the LILO prompt when booting the `a1` disk. See your distribution's documentation for details.

  You may not see an ``out of memory'' error when attempting to boot or install the software; instead, the system may unexpectedly hang, or fail to boot. If your system hangs, and none of the explanations in the previous section seem to be the cause, try disabling the ramdisk.

  Keep in mind that Linux itself requires at least 2 megabytes of RAM to run at all; some distributions of Linux require 4 megabytes or more.

- The system reports an error such as ```permission denied`'' or ```file not found`'' while booting.

  This is an indication that your installation bootup media is corrupt. If you attempt to boot from the installation media (and you're sure that you're doing everything correctly), you should not see any errors such as this. Contact the distributor of your Linux software and find out about the problem, and perhaps obtain another copy of the boot media if necessary. If you downloaded the bootup disk yourself, try re-creating the bootup disk, and see if this solves your problem.

- The system reports the error ```VFS: Unable to mount root`'' when booting.

  This error message means that the root filesystem (found on the boot media itself), could not be found. This means that either your boot media is corrupt in some way, or that you are not booting the system correctly.

  For example, many CD-ROM distributions require that you have the CD-ROM in the drive when booting. Also be sure that the CD-ROM drive is on, and check for any activity. It's also possible that the system is not locating your CD-ROM drive at boot time; see Section 2.5.2 for more information.

  If you're sure that you are booting the system correctly, then your bootup media may indeed be corrupt. This is a very uncommon problem, so try other solutions before attempting to use another boot floppy or tape.

Next: 2.5.2 Hardware problems Up: 2.5 Running Into Trouble Previous: 2.5 Running Into Trouble