<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN"> <HTML> <HEAD> <META NAME="GENERATOR" CONTENT="SGML-Tools 1.0.9"> <TITLE>UMSDOS HOW-TO: Installation/UN-installation and some tricks</TITLE> <LINK HREF="UMSDOS-HOWTO-8.html" REL=next> <LINK HREF="UMSDOS-HOWTO-6.html" REL=previous> <LINK HREF="UMSDOS-HOWTO.html#toc7" REL=contents> </HEAD> <BODY> <A HREF="UMSDOS-HOWTO-8.html">Next</A> <A HREF="UMSDOS-HOWTO-6.html">Previous</A> <A HREF="UMSDOS-HOWTO.html#toc7">Contents</A> <HR> <H2><A NAME="s7">7. Installation/UN-installation and some tricks</A></H2> <P>The installation of a <EM>Umsdos</EM> is not much different from the installation of an ordinary (<EM>Ext2 based</EM>) <EM>Linux</EM> system. <P>There are two main differences. <P> <H2><A NAME="ss7.1">7.1 The pseudo-root <CODE>/mnt/linux</CODE></A> </H2> <P>The normal steps for an installation are <P> <OL> <LI>Setting a partition with fdisk and formatting it.</LI> <LI>Mounting it as /mnt relative to our installation root disk.</LI> <LI>Copy all packages into <CODE>/mnt</CODE>.</LI> </OL> <P>With <EM>Umsdos</EM>, the step 1 is not required (wasn't it the goal of <EM>Umsdos</EM> not to reformat ?). <P>It is possible to install a <EM>Umsdos</EM> system just by copying all packages into <CODE>/mnt</CODE>. This will certainly work. But it will create a bunch of subdirectories into your <EM>DOS</EM> root directory (C:) and you won't like it. This is the reason all <EM>Umsdos</EM> installation use the pseudo-root. And this is the major difference between a normal <EM>Ext2</EM> installation and a <EM>Umsdos</EM> one: All files are copied into <CODE>/mnt/linux</CODE>. <P> <H2><A NAME="ss7.2">7.2 Preparing <CODE>/mnt/linux</CODE></A> </H2> <P><CODE>/mnt/linux</CODE> is not an ordinary directory. It has to be promoted so it will correctly handle <EM>Linux</EM> long file name and special files (links, device). The step required to setup <CODE>/mnt/linux</CODE> are: <P> <OL> <LI><CODE>mkdir /mnt/linux</CODE></LI> <LI><CODE>umssync /mnt/linux</CODE></LI> </OL> <P>That's it! <P> <H2><A NAME="ss7.3">7.3 Making sure <CODE>/mnt/linux</CODE> is correctly setup</A> </H2> <P>Even if the setup of <CODE>/mnt/linux</CODE> is pretty simple, there are many installation package out there who get it wrong. How can ? <P>The biggest installation problem come from an incompatible <CODE>umssync</CODE> program. <EM>Umsdos</EM> has been update in linux 1.1.88 (Can't remember exactly) and a flaw was uncovered in <CODE>umssync</CODE>. To avoid confusion in the <EM>Linux</EM> community, it was decided to raise the compatibility level required for all <EM>Umsdos</EM> tools. Old version of the tools were simply rejected. <P>It sounds like many distribution did not update their <CODE>umssync</CODE> utility on the installation disk. <P>There are still many distribution like this out there. The net result is that the directory <CODE>/mnt/linux</CODE> is not promoted at all and will truncate all long file name and will reject all special file. <P>It is possible to do a test very early during the installation to find out if something went wrong. Thanks to the pseudo console mechanism of <EM>Linux</EM>, you can do that without leaving the installation program. Do the following steps: <P> <OL> <LI>Press <CODE>Alt-F2</CODE> (<CODE>Alt</CODE> key at the same time as the <CODE>F2</CODE> key).</LI> <LI>login as root.</LI> <LI><CODE>cd /mnt/linux</CODE> If this fail, you are trying this too early. A good time to do this is at the end of the packages selection.</LI> <LI><CODE>>TOTO</CODE></LI> <LI><CODE>ls -l</CODE> You should see an empty file <CODE>TOTO</CODE> in uppercase. If you see it in lowercase, something went wrong. Try to do the <CODE>umssync</CODE> step again. <CODE>umssync</CODE> can be use over and over without problem. <CODE>umssync .</CODE> If there is no error message, try the <CODE>TOTO</CODE> test again. If <CODE>TOTO</CODE> appears fine, then all is OK. Something is strange in this installation, but you just save it. Continue </LI> <LI>Press <CODE>Alt-F1</CODE> to get back to the installation screen.</LI> </OL> <P>If the test fail, the best fix is to get a newer installation root disk. You can generally fix this root disk by installing a newer version of <CODE>umssync</CODE>. This is not difficult but required a working <EM>Linux</EM> system. You simply have to mount the root disk floppy and replace the offending <CODE>umssync</CODE> with a new one. <P> <H2><A NAME="ss7.4">7.4 Oops releasing pseudo root ...</A> </H2> <P>Most <EM>Umsdos</EM> installation which fail, do this by printing this strange message. This is not a bug in <EM>Umsdos</EM> although the message looks strange. Here are the known causes. <P> <UL> <LI>The most common one <P>The <EM>Slackware</EM> installation try to setup a swap file very early during the installation. To do so, it asks you to select a partition (dos drive), then mount it and set the swap file. <P>When installing a <EM>Slackware</EM> system, you must setup the target partition prior to install. This normally mounts the <EM>DOS</EM> partition on <CODE>/mnt</CODE>, creates the <CODE>/mnt/linux</CODE> directory and applies <CODE>umssync</CODE> on it. <P>This is where most problems come from. Most user just forget the "setup target partition" step and go directly to the rest of the installation. Since <CODE>/mnt</CODE> is already mounted, this mistake goes unnotice. This means that <CODE>/mnt/linux</CODE> was not created properly (Not promoted). All special files and links and long names can't be created properly. <P> </LI> <LI>Invalid umssync utility <P><CODE>/mnt/linux</CODE> was improperly setup-ed. Generally caused by an improper <CODE>umssync</CODE> utility on the installation root disk. </LI> <LI>Old bug in umsdos <P>There was a bug in <EM>Umsdos</EM> prior to <EM>Linux 1.2.2</EM>. The pseudo-root mode would not activate properly if the file <CODE>/etc/init</CODE> was missing. <CODE>init</CODE> is now located in <CODE>/sbin</CODE>. You can fix it by getting a newer kernel. This is recommended because another bug was uncover and fixed in 1.2.2. <P>If you can't upgrade, do this <P> <OL> <LI>Boot from you installation disk.</LI> <LI>Login as root.</LI> <LI><CODE>mount -t umsdos /dev/hdXX /mnt</CODE> where <CODE>/dev/hdXX</CODE> is your <EM>DOS</EM> partition.</LI> <LI><CODE>cd /mnt/linux/etc</CODE></LI> <LI><CODE>ln -s ../sbin/init init</CODE></LI> <LI><CODE>cd /</CODE></LI> <LI><CODE>Ctrl-Alt-Del</CODE></LI> <LI>Boot your <EM>Umsdos</EM> normally.</LI> </OL> </LI> </UL> <P>Unfortunatly, the first two (Installation problems) produce a completly unusable installation. Uninstall it (See next section) and install again. <P> <P> <H2><A NAME="ss7.5">7.5 How to UN-install a <EM>Umsdos</EM> system</A> </H2> <P>One neat thing about <EM>Umsdos</EM> and its pseudo-root mechanism, is that you can UN-install it without pain. You just boot <EM>DOS</EM> and recursively delete the <CODE>linux</CODE> directory. That's all. <EM>Umsdos</EM> requires no special drivers in the config.sys, nor it creates anything special outside of the <CODE>linux</CODE> directory. <P> <H2><A NAME="ss7.6">7.6 Moving a <EM>Umsdos</EM> system to another <EM>DOS</EM> drive</A> </H2> <P>This can be done from <EM>Linux</EM> or from <EM>DOS</EM>. You just have to copy recursively the <CODE>linux</CODE> directory from one drive to the other. After that you will have to adjust you boot mechanism (generally loadlin command) and the <CODE>/etc/fstab</CODE> file. <P><EM>Umsdos</EM> can live on any <EM>DOS</EM> drive. There is no need to install it on the <CODE>C:</CODE> drive, nor it is important to have it on the first hard drive. It does not matter at all. <P>In fact, one may decide to have several <EM>Umsdos</EM> installations on different drive just to do experiments. <P> <H2><A NAME="ss7.7">7.7 About installing 50 <EM>Umsdos</EM> systems.</A> </H2> <P>How about installing a bunch of <EM>Linux</EM> systems in no time ? <P><EM>Umsdos</EM> systems are living in a <EM>DOS</EM> world. You can take advantage of this if you wish to install <EM>Linux</EM> easily. <P>You can install and configure a <EM>Umsdos</EM> system at your site. When you are satisfied with the configuration and the different packages you have selected, you can boot <EM>DOS</EM> and copy the complete <CODE>linux</CODE> directory to your <EM>DOS</EM> file server. Then you go to other <EM>DOS</EM> station and simply copy the files on the network drive to the local drive. That's it. Only adjust the boot script (<EM>Loadlinx</EM>) and go. <P>With minimal adjustment (Host name, IP number), anyone will be able to install a <EM>Linux</EM> system in a matter of minute. <P>Interest readers may note that installing <EM>Linux</EM> systems by copying running system also works for any other <EM>Linux</EM> systems, including <EM>Ext2</EM> based one. <P>One beauty of <EM>Linux</EM> is that there is no hidden files which have to be install by magic installation program. <P> <HR> <A HREF="UMSDOS-HOWTO-8.html">Next</A> <A HREF="UMSDOS-HOWTO-6.html">Previous</A> <A HREF="UMSDOS-HOWTO.html#toc7">Contents</A> </BODY> </HTML>