Date: Tue, 23 Jul 2002 19:36:52 +0200 From: "Siegbert Baude" <Siegbert.Baude@gmx.de> To: <justsovanilla@yahoo.co.in> Cc: <freebsd-questions@freebsd.org> Subject: Re: Installing on a logical DOS partition Message-ID: <001601c2326f$88330980$406a3c86@whwurm.uniulm.de> References: <1027437286.70211ffcjud@myrealbox.com>
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Hi Piyusch, Piyush wrote: > The program shows the primary dos partition and extended dos partition but > not any logical partitions under the extended partition......the logical > partition on which I wish to install Fbsd is the last one.......if I delete > a 'slice' of a particular size will fbsd delete any other partitions? Jud wrote: > The second alternative might work if you have Linux > handy and it groks Windows logical and extended > partitions (I don't know anything about Linux). Try > deleting the DOS partition, changing it to a > Linux partition, and see if FreeBSD understands it. > If it does, install there. This way will work, but be very careful, you are operating on the heart of your hard disk management. So if you have any precious data on this disk: Backup first, make sure you can retrieve your data from these backups! So then in Linux call your fdisk like: fdisk /dev/hda change the display of the units with the "u" command as it is easier to handle LBA block numbers than CHS numbers. Type "p" and write down all the numbers. This will enable you to restore the state of your hard disk, if anything goes wrong. Changing the MBR doesn`t actually destroy your data, but can make it impossilbe to access it anymore. If you exactly restore the information you just wrote down, it is possible to regain access. You were lucky so far, as the partition you want to use is the last in your extended partition. This makes it easy to reduce the size of the extended partition and reuse the gained space for a primary partition. So if your layout is for example like: primary partition 1: LBA 1 - LBA 10000 extended partition: LBA 10000 - LBA 40000 logical partition 1: LBA 10000- LBA 20000 logical partition 2: LBA 20000- LBA 30000 logical partition 3: LBA 30000- LBA 40000 Maybe the beginning of logical partition 1 is actually on 10001 (one block needed to write the EMBR), but this is not important. Just use the numbers as you have them now. Now you want to use logical partition 2 then you have to get to the following layout: primary partition 1: LBA 1 - LBA 10000 extended partition: LBA 10000 - LBA 30000 logical partition 1: LBA 10000- LBA 20000 logical partition 2: LBA 20000- LBA 30000 primary partition 2: LBA 30000- LBA 40000 You get the idea? So the first thing is to delete logical partition 3 (Linux fdisk would probably show this as partition 7). Then you have to resize the extended partition, i.e. adjusting the end block from 40000 to 30000. I don't know, if Linux fdisk will allow this directly or if you have to delete all the logical and extended partitions first and then recreate them with the correct numbers. Just try, there will be no harm, if you just quit the fdisk with "q". Only if you hit "w" the changes are actually written to disk! If you have the correct values for the extended partition and logical partition 1 and 2 create a new primary partition 2 with "n" and give it all the available space you just freed by deleting logical partition 3. To be sure you can change the type to FreeBSD, but I believe FreeBSD sysinstall will recognize the primary partition independent of its type. So it should be possible to install FreeBSD there now. If what I wrote is not clear to you, ask first before dong dumb things. Maybe this is a good time to pay your local guru a beer to accompany your steps. :-) BTW, it is possible to use logical partitions as FreeBSD mount devices, but you have to do all the magic by hand, as the tools don`t support this. And final note: In FreeBSD DOS/Linux partitions are called slices. Such a slice is then separated into FreeBSD partitions (no DOS/Linux equivalent exists) with sysinstall. FreeBSD partition c is the complete disk, a ist the partition which contains the / mount point, b is swap space. So you can use d and up for /var, /usr, ... mount points, if you want. Ciao Siegbert To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
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