freebsd/share/doc/handbook/troubleshooting.sgml

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<!-- The FreeBSD Documentation Project -->

<chapt><heading>Troubleshooting<label id="troubleshooting"></heading>

<p>The following tips and tricks may help you turn a
	failing (or failed) installation attempt into a success.
	Please read them carefully.

<sect>
      <heading>Hardware conflict or misconfiguration</heading>


      <p><descrip>
	  <tag>Problem:</tag> A device is conflicting with
	another or does not match the kernel's compiled-in IRQ or
	address.

	  <tag>Cause:</tag> While most device drivers in
	FreeBSD are now smart enough to match themselves to your
	hardware settings dynamically, there are a few that still
	require fairly rigid configuration parameters to be
	compiled in (and matched by the hardware) before they will
	work.  We are working hard to eliminate as many of these
	last hold-outs as we can, but it is not always as easy as
	it looks.

	<tag>Solution:</tag> There are several possible
	solutions.  The first, and easiest, is to boot the kernel
	with the <tt>-c</tt> flag.  When you see the initial boot prompt
	(from floppy or hard disk), type:

<tscreen><verb>
/kernel -c
	  </verb></tscreen>

	This will boot just past the memory sizing code and then
	drop into a dynamic kernel configuration utility.  Type
	`<tt>?</tt>' at the prompt to see a list of commands.
	You can use this utility to reset the IRQ, memory
	address, IO address or a number of other device
	configuration parameters.  You can also disable a device
	entirely if it is causing problems for other devices you would
	much rather have work.

	Another solution is, obviously, to remove the offending
	hardware or simply strip the system down to the bare
	essentials until the problem (hopefully) goes away.  Once
	you are up, you can do the same thing mentioned
	above---compile a kernel more suited to your hardware, or
	incrementally try to figure out what it was about your
	original hardware configuration that did not work.

	</descrip>

<sect>
      <heading>When I boot for the first time, it still looks for
	/386bsd!</heading>

      <p>Cause: You still have the old FreeBSD 1.x boot blocks on
	your boot partition.

	Solution: You should re-enter the installation process,
	invoke the (F)disk editor and chose the (W)rite option.
	This will not hurt an existing installation and will make
	sure that the new boot blocks get written to the drive.
	If you are installing for the first time, do not forget to
	(W)rite out your new boot blocks! :-)