Ideal partition sizes

[Marilyn de Queiroz]

If I want to have a dual partition using Red Hat Linux on one partition and Win2K on the other partition on a 13 GB hard disk, should I divide it half and half?

Do I need to put the root (does root=boot) of Linux in the first 1024 bytes or in its own partition?

[Andrew Monkhouse]

Hi Marilyn

If I want to have a dual partition using Red Hat Linux on one partition and Win2K on the other partition on a 13 GB hard disk, should I divide it half and half?

Do you have any feeling for how much you will be installing / using each system?
My workstation has a 12Gb drive: 2Gb Windows 2000 (I almost never use it - came with the computer) and 10 Gb Linux (nearly full).
Whereas my girlfriend started using the computer I intended as my new server, and I never got it back from her So she has 80 Gb Windows 2000 and no Linux partition.

Do I need to put the root (does root=boot) of Linux in the first 1024 bytes or in its own partition?

On older bioses you used to need to boot from the first 1024 cylinders of the hard drive (no matter what OS). Most modern Bioses do not have this limitation.
root != boot by the way. boot is in a directory named /boot (wow - who thinks of these naming schemes? ). In the old days when I know it made a difference, we used to make a 100Mb partition for /boot, a partition for Windows, and the final partition for the major Linux installation. That way both Linux and Windows were able to boot below the magic problem point for the bios.
Regards, Andrew

[Tim Holloway]

For recent Red Hats, I'd set aside about 5GB for the OS and software, plus any Linux-only data. You can mount FAT32 partitions in Linux, allowing for the different access right structure. NTFS partitions are mountable read-only, alas.
Grub and modern-day LILO's read the boot program from cylinder 0 (assuming you installed them there) and then kick into their own "BIOS" that can cover the full extent of the disk. Older LILOs did have problems with the 1024K cylinder limit.

[Greg Harris]

hi marilyn! glad to see you in the linux forum.
i have built dual-boot boxes in the past and i just put redhat on a new dell laptop... i never worried about the 1024 cylinder issue until now, though.
like tim said, you can mount the windows partition from linux, so you can make windows bigger if you want to. or, create 3 partitions, and used 1 for windows, 1 for linux and 1 for file storage. i think this would be the better option because you do not hve to worry about win2k's filesystem. make sure you create the file storage partition as an FAT32 so it will be easier to mount with linux.
as for the 1024 issue, i do not think it really matters, but i used it for my install. when i put win2k and redhat 7.1 together a couple years ago, i seem to remember that you need to install redhat AFTER win2k because win2k overwrites your boot sector.
so, create a very small boot partition for linux in the first few cylinders. then create a partition for win2k. after that, you can install win2k and then install redhat and create your swap and /root partitions manually in the unpartitioned space with disk druid or fdisk.
hope this helps... email me direct if you have anymore questions becuase i know i owe you!

[Marilyn de Queiroz]

On older bioses you used to need to boot from the first 1024 cylinders of the hard drive (no matter what OS). Most modern Bioses do not have this limitation.

How old is an "older bios"? I think mine is fairly new.

root != boot by the way. boot is in a directory named /boot.



In the old days when I know it made a difference, we used to make a 100Mb partition for /boot, a partition for Windows, and the final partition for the major Linux installation. That way both Linux and Windows were able to boot below the magic problem point for the bios.

I was thinking something like that. It seems that (many years ago) I partitioned my hard drive into DOS/Win3.1 and a data partition and created a separate partition for boot.

I was kinda thinking that, since I have another machine with only Win2K on it, that I probably only need a pretty minimal Win2K(NTFS) ~4GB on the dual-boot one. That way, if the Win one dies, I can just move the hard drive over to the dual boot one as a second hard drive and basically just boot off of the dual-boot HD while most of the applications would be on the 2nd HD.

Then, as I was reading more about partitions, I thought I might make a partition just for data (Fat32), maybe a couple of GB, and use the other 5 GB for Linux. Would that leave me enough room to install the JDK and do a little Java work in the Linux part? I would keep all the source files in the data partition?

[Marilyn de Queiroz]

Originally posted by Tim Holloway:
Grub and modern-day LILO's read the boot program from cylinder 0 (assuming you installed them there)

How can I be sure the /boot directory is installed at cylinder 0?

[Andrew Monkhouse]

Tim Holloway: Grub and modern-day LILO's read the boot program from cylinder 0 (assuming you installed them there)
Marilyn de Queiroz: How can I be sure the /boot directory is installed at cylinder 0?

You don't need the /boot directory at cylinder 0.
Lilo or grub is just the boot loader (typically less than 1Kb of code). All they do is find the kernel in /boot (or the other OS's boot code) and run it.
Older lilo's (thanks Tim for clarifying) needed to find the /boot partition within the first 1024 cylinders. Now that should no longer be a problem.

Marilyn de Queiroz: Then, as I was reading more about partitions, I thought I might make a partition just for data (Fat32), maybe a couple of GB, and use the other 5 GB for Linux. Would that leave me enough room to install the JDK and do a little Java work in the Linux part?

From the RedHat technical requiements page for RedHat 9 (http://www.redhat.com/software/linux/technical/):
CPU:
Minimum: Pentium-class
Recommended for Text Mode: 200 Megahertz Pentium-class or better
Recommended for Graphical Mode: 400 Megahertz Pentium-class or better
Hard Disk Space*:
Custom installation (minimum): 475 MB
Personal Desktop: 1.7 GB
Workstation: 2.1 GB
Custom installation (everything): 5.0 GB
Memory Requirements:
minimum for text mode: 64MB
minimum for graphical mode: 128 MB
recommended for graphical mode: 192 MB
So unless you are going to install everything 5 Gb should be plenty.
If you are not going to go with the latest from RedHat - earlier releases were a little less hungry.
Some sizes for additional packages (all sizes are in Kb):

[root@andrewm root]# cd /opt
[root@andrewm opt]# du -ks *
4264    checkstyle-3.0
1124    doccheck1.2b1
13356   jakarta-ant-1.4.1
30024   jakarta-tomcat-4.1.18
249920  JBuilder8
13664   JBuilder8.AddOns
1500    junit3.8.1
4448    sqltools
[root@andrewm opt]# cd /usr/java
[root@andrewm java]# du -ks *
5908    beans
82072   j2sdk1.4.0_01

So if all you want is the JDK itself, you will need 82Mb.
Of course, you will need temporary space to store the sources - but they can be removed as soon as you have done your installation.
Regards, Andrew

[Tim Holloway]

Originally posted by Marilyn de Queiroz:

How can I be sure the /boot directory is installed at cylinder 0?

It's not. What's at Cylinder 0 is the Master Boot Record (MBR). The BIOS boot reads the first n (n= 1? 3? 5? ??? I forget) sectors off cylinder 0, track 0 into RAM, then jumps to the boot code.
The other thing that's kept down there is the partition maps (partition table).
Usually when you buy a disk drive these days it comes with something like EZ-BIOS. EZ-BIOS slips itself into the MBR locations, and hoists the MBR up a track or so. That way when you boot, it loads up a patch to the BIOS to handle the 1024-cylinder limit and futzes the BIOS disk calls to hide itself.
Linux doesn't need EZ-BIOS, though, since it's not using the BIOS. As long as you're running anything about about Red Hat 7.2, their LILO will take care of it for you. The warnings on installation are more to remind you that if you have multiple OS's, like Windows NT on the disk, they may not fare as well.

[Marilyn de Queiroz]

So are you trying to tell me that I don't need to worry about creating a partition to boot either Win or Linux? That the installation(s) will handle that for me?

[Andrew Monkhouse]

At some point you are going to have to create the partitions. But you can normally do that from within the installation programs for both Windows 2000 and Linux. As you install, they should give you an option of specifying how much hard drive space you want to allocate to their respective systems.
What we are saying is that we dont think you need to worry about where the partitions are created: you should not need to worry about whether you are within the first 1024 cylinders or not. The boot loaders will take care of themselves.
Regards, Andrew