On Wed, 9 Jun 1999, Kevin Nelson wrote:
> 1) How can verify how many CPU's are actually being used? I have tried
> top and "cat /proc/cpuinfo". Both seem to indicate only one CPU.
Most of these questions are in the FAQ (see URL below, in case you
missed it) or in HOWTOs in /usr/doc, or in many, many Linux books
available at e.g. Barnes and Noble. Still:
top might well be mistaken (only certain patches of top and the kernel
permit multiple CPU's to be separately shown), but if /proc/cpuinfo (or
the boot time messages that scrolled by and can be reviewed via dmesg)
only indicate one CPU, then you are either running a UP kernel or have
only one functional CPU (don't laugh -- three "dual CPU" systems have
been shipped to me in the past with only one CPU installed due to vendor
error, and needless to say there was a certain amount of frustration
involved in trying to get them to run SMP until I actually opened them
up and looked...:-).
> 2) gnome-linuxconf indicates there are two kernels in the system, one
> for SMP. How do I know which one actually loaded?
The first one in /etc/lilo.conf usually is the one actually booted. I
like to use the following in /etc/lilo.conf:
prompt # prompt for the OS/Kernel to boot
timeout = 100 # wait ten seconds for it to be entered
message = /etc/lilo.msg # Tell us about the choices
prompt forces lilo to give you a boot prompt like
boot:
at the beginning instead of just booting the leading default. timeout
of 100 gives you ten seconds to type something or it boots the default
anyway (don't want it to wait forever or it will never reboot after a
power outage). The message is printed on the screen right before the
boot prompt appears and is typically something that describes your boot
choices. If you add any of this stuff by hand (or modify what you've
already go) be sure to rerun lilo when you're done.
> LILO linux configurations
> linux /dev/sdb1 /boot/vmlinuz-2.2.5-15smp
> linux-up /dev/sdb1 /boot/vmlinuz-2.2.5-15
>
> Uh, does the "linux-up" mean what I fear it does?
It probably means linux-u(ni)p(rocessor). If you have both
possibilities installed in lilo, you ought to be able to arrange for
either one to boot. Even the smp kernel will often boot on a UP system
as long as the UP system is modern enough. There are more than enough
exceptions that they don't make the default kernel smp, but maybe one
day...
You can therefore choose your kernel at boot time. Enter
boot: linux
to boot the SMP kernel. Enter
boot: linux-up
to boot the UP kernel. If you boot the SMP kernel and still find only
one CPU listed in /proc/cpuinfo, open your case and count the CPUs (no
kidding) and if you find two of them pop them both out and reseat them.
You almost certainly have a hardware problem, be it a missing CPU or one
that is dead or one that is improperly seated or a broken motherboard.
> 3) Are there any ways to boot the system, in case the non-SMP kernel is
> being used, so that I can find out why the default SMP kernal was
> rejected? Is there a log file I can check?
See the above. At the boot prompt, you can boot any kernel you like.
Move the one you want to be default so it is the first set in
/etc/lilo.conf. Needless to say, read the copious documentation on lilo
in /usr/doc and the man page(s) and possibly get a boot or two on Linux
management -- they will save you lots of time and hassle.
> Since I have also installed Windows 2000 Server on the same computer
> (first drive, second partition; linux is on second drive), I currently
> boot the system from a floppy disk.
Lilo "should" be perfectly happy dual booting Windows and Linux from the
boot block of the first partition/first disk. Add a section to lilo
like:
# WinXX bootable partition config begins
other = /dev/sda4
label = winXX
table = /dev/sda
# WinXX bootable partition config ends
where /dev/XXXX is the device on which Window resides (probably
/dev/hda1 or /dev/sda1 on your system, depending on whether it is ide or
scsi). Once this is done, you can enter
boot: winXX
at the boot prompt to boot windows or enter linux to boot linux-smp, or
enter nothing and wait to boot the default. Other options allow you to
boot single user (often useful!) or to enter specific module
configuration data or... again, get a decent book or two on linux
systems management. You won't regret it. Most of this is
straightforward, but it does help to have a decent book or manual to
guide you.
If you are booting from floppy, by the way, nothing you do to
/etc/lilo.conf on your linux HD installation will make any difference,
and chances are the kernel you are booting is whatever is on the floppy.
A "random" boot floppy is likely to be UP simply because that is the
lowest common denominator -- an SMP system will always boot a UP kernel
(with just one processor in use) but the converse is not always true.
rgb
Robert G. Brown http://www.phy.duke.edu/~rgb/
Duke University Dept. of Physics, Box 90305
Durham, N.C. 27708-0305
Phone: 1-919-660-2567 Fax: 919-660-2525 email:[EMAIL PROTECTED]
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