====== Running Multiple Operating Systems ======


===== Booting MINIX 3 Directly =====
MINIX 3 uses a close derivative of [[http://netbsd.gw.com/cgi-bin/man-cgi?boot|NetBSD boot loader]] and [[http://netbsd.gw.com/cgi-bin/man-cgi?mbr+8|MBR boot code]]. Just as with NetBSD, it can coexist on a hard disk with installations of NetBSD, Windows, or Linux; by installing the //extended// boot code, it is possible to choose one or another partition and then boot the corresponding operating system without disturbing the others.


===== Using GRUB 2 to boot MINIX 3 =====
GRUB 2 stores its configuration in a file called //grub.cfg// (usually ///boot/grub/grub.cfg//) but you shouldn't edit it directly as it is generated with the information given in ///etc/default/grub// and the files in ///etc/grub.d//.\\
To boot MINIX 3 with GRUB 2 there's two alternatives:
==== add a menu entry for loading the MINIX bootloader ====
Edit ///etc/grub.d/40_custom// (you will probably have to be root to do so) and add the following code:

<code>
menuentry "MINIX 3" {
        set root=(hdX,Y)
        chainloader +1
}
</code>

Here are some examples of GRUB's naming convention for the disks and partitions:

  * (hd0,1) - first primary partition on first hard disk
  * (hd0,2) - second primary partition on first hard disk
  * (hd0,3) - third primary partition on first hard disk
  * (hd0,4) - fourth primary partition on first hard disk
  * (hd1,1) - first primary partition on second hard disk
  * (hd1,2) - second primary partition on second hard disk
  * and so on

<!> Note: GRUB 1 and GRUB 2 have different naming conventions for partitions.

Alternatively, if you want to use GRUB to boot MINIX directly:

==== add a menu entry for MINIX ====
The entry should have this shape:
<code>
menuentry "Minix Latest" {
        set root=(hd0,3,1)
        multiboot /boot/minix_latest/kernel rootdevname=c0d0p2s0
        module /boot/minix_latest/mod01_ds.gz
        module /boot/minix_latest/mod02_rs.gz
        module /boot/minix_latest/mod03_pm.gz
        module /boot/minix_latest/mod04_sched.gz
        module /boot/minix_latest/mod05_vfs.gz
        module /boot/minix_latest/mod06_memory.gz
        module /boot/minix_latest/mod07_tty.gz
        module /boot/minix_latest/mod08_mfs.gz
        module /boot/minix_latest/mod09_vm.gz
        module /boot/minix_latest/mod10_pfs.gz
        module /boot/minix_latest/mod11_init.gz
}
</code>

If your disk is configured as a native SATA (AHCI) device, you will need to include the line ''set ahci=yes'' in the entry.


==== [optional] un-hide the boot menu on startup ====
Edit ///etc/default/grub// and change ''GRUB_HIDDEN_TIMEOUT=0'' to ''# GRUB_HIDDEN_TIMEOUT=0''.\\
(You can also press //shift// during GRUB's startup to show the boot menu.)

==== generate new grub.cfg ====
Run **''grub-mkconfig''** as root to rewiew the new configuration.\\
Run **''grub-mkconfig -o /boot/grub/grub.cfg''** as root to overwrite your old //grub.cfg// with the new configuration. \\
(change the path to your //grub.cfg// if it differs from the one given above)


===== Using GRUB 0.9x (GRUB1) to boot MINIX 3 =====
To have GRUB1 boot MINIX, you can just add the following lines to your GRUB config file (typically ///boot/grub/menu.lst//):

<code>
title Minix
rootnoverify (hdX,Y) # (hdX,Y) is the disk and partition where you install Minix
chainloader +1       # tells GRUB to call Minix's boot loader
</code>
Here are some examples of GRUB's naming convention for the disks and partitions:

  * (hd0,0) - first primary partition on first hard disk
  * (hd0,1) - second primary partition on first hard disk
  * (hd0,2) - third primary partition on first hard disk
  * (hd0,3) - fourth primary partition on first hard disk
  * (hd1,0) - first primary partition on second hard disk
  * (hd1,1) - second primary partition on second hard disk
  * and so on

<!> Note: GRUB 1 and GRUB 2 have different naming conventions for partitions.

===== Using MINIX3 CD-ROM =====
If you don't want to use a multiboot loader, you can use the MINIX 3 CD-ROM to boot MINIX.

Don't forget to change the //Boot Order// in your BIOS if necessary. You want to boot from the CD before booting from disk.

  * Insert the MINIX 3 CD-ROM and boot
  * Stop at the MINIX 3 boot monitor (pressing space)
  * Type 4 to drop to boot prompt
  * Now type <fs small>(assuming a US keyboard, so '':'' is on the key right to L)</fs>:
<code>
dev hd0i:
</code>
to boot from the operating system image file on BIOS drive 0, first MINIX sub-partition. If your installation is complex or if you are unsure, use:
<code>
dev
</code>
to list all the recognized partitions.

  * Then type <fs small>(again assuming US keyboard, so ''*'' is shifted 8 key, ''_'' is the shifted key right to 0, and ''/'' is at lower right)</fs>:
<code>
load_mods /boot/minix_latest/mod*
multiboot /boot/minix_latest/kernel rootdevname=c0d0p0s0
</code>
assuming you want to boot the //latest// image of MINIX and to use the root file system found by MINIX at controller 0, drive 0, partition 0, subpartition 0; append
<code>
ahci=yes
</code>
if your system uses [[.:sata|SATA]] disks; any other [[.:bootmonitor|boot monitor]] parameter can also be appended.

===== Archives =====
MINIX used to have other ways to coexist with other operating systems, and many people wrote about it. You can find some pointers on [[:releases:3.2.0:usersguide:multipleoperatingsystems|the previous version]] of this wiki page. However, much of it is outdated and does not apply directly to current versions of MINIX3.