Good afternoon, Michael,
On Sun, 9 Jul 2000, Michael H. Collins wrote:
> I may be dense, but what is the function or purpose of this? I think
(Actually, I'm the one who should have pointed out the use of this
right from the start. Thanks for the nudge.)
> I understand what you are doing, just not why. Is it sort of a VM?
You have it exactly right; user-mode-linux is a virtual machine
that allows you to start a new kernel running as a userspace program.
The UML kernel opens a file called root_fs (stored on the host filesystem)
that holds a root filesystem for the uml kernel.
The host kernel and uml kernel can be completely different
versions with different features. This allows you to, say, try out the
2.3.x kernels with no fear of mangling your main root filesystem.
Likewise, the host filesystem and the uml root filesystem stored
in root_fs can be of different distributions, allowing one to, say use
RedHat 6.x as the host environment, but run different UML sessions with
Debian, Slackware, SuSE, and now tomsrtbt in different terminals. All at
once.
For those familiar with VMWare, think of it as a free VMWare that
only supports Linux (true for both host and client at the moment), with
almost none of the overhead incurred by VMWare.
Cheers,
- Bill
> William Stearns wrote:
> > Quick summary - Thanks to the magnificent efforts of Tom Oehser
> > and Jeff Dike, I've got a functioning root filesystem built from Toms
> > Root/Boot that runs under User-Mode-Linux.
> > For those unfamiliar with Toms Root/boot: Toms Root/Boot is a
> > single floppy Linux environment that's usable as a rescue disk or Linux
> > text console. It packs a lot of tools into a 1.7M floppy. More info at
> > http://www.toms.net/rb/
> > For those unfamiliar with User-Mode-Linux: UML is a linux kernel
> > that has been compiled to run as a standard Linux executable. It is
> > started from the command line just like any other binary. It boots up,
> > loads its root filesystem from a file called root_fs, and allows you to
> > log in just like any other linux system. More info at
> > http://user-mode-linux.sourcefore.net
P.S. This should have been:
http://user-mode-linux.sourceforge.net
> > My small contribution has been preparing the content in Toms
> > Root/Boot to be usable as a root filesystem for UML. It seems to boot up
> > just fine. It's not a finished product, but it's certainly usable and I'd
> > love to get feedback.
[snip]
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William Stearns ([EMAIL PROTECTED]). Mason, Buildkernel, named2hosts,
and ipfwadm2ipchains are at: http://www.pobox.com/~wstearns
LinuxMonth; articles for Linux Enthusiasts! http://www.linuxmonth.com
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