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Xref: sserve comp.os.os2.setup:14083 comp.os.os2.misc:104167 comp.os.linux.misc:23741 comp.os.386bsd.misc:3486 Path: sserve!newshost.anu.edu.au!munnari.oz.au!constellation!news.uoknor.edu!ns1.nodak.edu!netnews.nwnet.net!news.u.washington.edu!tzs From: tzs@u.washington.edu (Tim Smith) Newsgroups: comp.os.os2.setup,comp.os.os2.misc,comp.os.linux.misc,comp.os.386bsd.misc Subject: My disk layout (was Re: OS/2 vs. OS/2 for Windows) Date: 7 Sep 1994 20:30:45 GMT Organization: University of Washington School of Law, Class of '95 Lines: 126 Message-ID: <34l7tl$p5b@news.u.washington.edu> References: <1994Aug26.202142.24982@midway.uchicago.edu> <33m1r8$f1q@news-slave1.openlab.advantis.net> <33nmieINNmbt@no-names.nerdc.ufl.edu> NNTP-Posting-Host: stein3.u.washington.edu Keywords: boot manager [I've added a linux group and a BSD group, since this may be of interest to them too] Greg Thoman <thoman@tcad.ee.ufl.edu> wrote: > Here's my curiosity question of the day: suppose I have two >physical drives, the first with a primary partition or partions and >an extended partition or partitions, and the second with only extended >partition or partitions. I know I can install OS/2 into an extended >partition, but can I install it into an extended partition on the >_second_ drive? This would mean "booting" from the second hard >drive to run it, which doesn't seem "intuitively obvious". > Will it work? OS/2 is happy on the second drive, although I've not tried it in an extended partition. Here's my current setup, which has OS/2, DOS/Windows, Linux, and FreeBSD: Drive 1 (540 MB) # Type Size Start Cyl Part 1: Boot Manager 2 meg 0 Part 2: DOS 200 meg 3 Part 3: FreeBSD 320 meg 410 Drive 2 (1080 MB) Part 1: HPFS 40 MB 0 Part 2: Linux 500 MB 1023 Part 3: Linux 24 MB 2049 Part 4: Extended 150 MB 82 The extended partition is filled with a DOS partition at the moment. I'm going to delete that and make a new extended partition that takes up all the free space. I'll then put DOS, OS/2, Linux, or FreeBSD partitions in that as needed. The second Linux partition is a swap partition. Linux is quit happy living entirely in the top half of the disk, past the 1023 cylinder limit that plagues many systems. Boot manager is set up to allow booting DOS, OS/2, or FreeBSD. Linux is booted from DOS via the bootlin program. The config.sys in the DOS partition starts like this: SWITCHES=/F [MENU] menuitem=NORMAL, Normal DOS and Windows Configuration menuitem=LINUX, Linux Bootstrap menuitem=TLINUX, Linux Bootstrap (test kernel) [LINUX] SHELL=C:\BOOTLIN.COM LINUX [TLINUX] SHELL=C:\BOOTLIN.COM TLINUX [NORMAL] ...regular DOS config.sys stuff goes here... The "SWITCHES=/F" tells DOS not to wait three seconds displaying that "Starting MS-DOS" message before it continues processing config.sys (I bet a lot of people thought that it was doing something profound at that point, like calibrating timers or something...nope! It's just giving you time to admire that message!) Backups are currenlty handled by Linux and my Macintosh. Since Linux can read DOS and OS/2 partitions, I do backups by making a compressed tar archive from Linux, and then I ftp that to my Mac, where it can either just sit there, or get copied to tape, depending on what my disk usage is like on the Mac. I haven't done enough with FreeBSD to warrant doing a backup, but I'll probably back it up when needed the same way, except I'll do it from FreeBSD rather than from Linux. Here are some tips. First, when you are thinking of installing multiple operating systems, make a chart that answers the following for each OS: 1. Can it live on the second disk? If not, can it at least be mostly there, or must is be all on the first disk? (Answers: OS/2, Linux can live on the second disk, I don't know about DOS. I suspect that FreeBSD wouldn't mind, but the installation script refused to consider the possibility). 2. Does it need a primary partition, or can it live in an extended partition? (Answers: I believe that OS/2 and Linux can live in extended partitions, although I gave them primaries. I think DOS needs to boot from a primary. I don't know about FreeBSD). 3. Does the OS care about cylinders past 1023? (Answers: Linux does not. I don't know about the others). 4. How can it be booted? Linux seems to be the most flexible. It can live anywhere, doesn't care about cylinder limits, and can be booted in many ways (e.g., make it active, boot it from boot manager, install LILO (which has a zillion configurations), or boot it throught DOS). The boot issue is one to watch out for. Even if the OS has no trouble with extended partitions or the second disk or living past 1023, the boot code might. For example, boot code that uses BIOS probably can't deal with an OS that lives past 1023. You'll need to put a small boot partition for that OS somewhere that meets the requirements of the boot program, or make other arrangements (e.g., like I do with bootlin). One more thing to watch out for. If you are installing multiple operating systems, you've probably got an fdisk from each one. You really should only install an OS in a partition created by the OS's fdisk. I created a DOS partition from Linux. DOS likes to have its partitions start on a track boundary (e.g., the rest of the track that contains the partition map is not used). Linux doesn't care where they start, and so Linux fdisk by default does *NOT* skip to the start of the next track. I'm not sure quite what happened next, but I somehow was able to xcopy from DOS all my files into that new partition, repartition my first disk (the new partition was on the second), and then boot DOS from a floppy with the intention of restoring all those files I had copied to the second disk, and only then did DOS decide that it did not like that second disk. (I figureout out what was wrong, and was able to fix things by simply changing the partition map so that it said the partition started at a track boundary, and then shifting the whole filesystem up by 62 blocks. This sort of thing is not for the timid. I learned to respect that warning in the Linux documentation about only using Linux fdisk for making Linux partitions!). --Tim Smith