Hitchhiker's Guide to Openbsd

partition, so you can use 
quotas
to restrict the space they use, and if they fill the partition, no other parts of your 
system will be impacted. 
●
You may also want to create an 
/altroot
 partition, as described in 
daily(8)
. This can make a daily copy of 
http://www.openbsd.org/faq/faq4.html (31 of 43)9/4/2011 10:01:58 AM

---

4 - OpenBSD 4.9 Installation Guide
your 
/
partition, giving you an extra copy of your kernel and 
/etc
configuration files should something happen 
to your root partition. Obviously, the 
/altroot
partition needs to be at least as big as 
/
. If you have a second 
drive and have something else duplicating the rest of your disk, either software 
softraid(4)
 or a periodic copy 
using 
dump(8)
/
restore(8)
, this disk can be bootable after the removal of the primary disk. 
●
Compiling some 
ports
 from source can take huge amounts of space on your 
/usr
and 
/tmp
partitions. This is 
another reason we suggest using 
pre-compiled packages
instead. 
●
At least some editors use 
/var/tmp
for scratch space, and this often needs to be as big or bigger than the largest 
file you edit. If you plan on editing 500M files, your 
/var
or 
/var/tmp
partition will need to be much larger 
than your might have planned on. 
4.9 - Multibooting OpenBSD/i386
Multibooting is having several operating systems on one computer, and some means of selecting which OS is to boot. It 
is not a trivial task! If you don't understand what you are doing, you may end up deleting large amounts of data from your 
computer. New OpenBSD users are strongly encouraged to start with a blank hard drive on a dedicated machine, and 
then practice your desired configuration on a non-production system before attempting a multiboot configuration on a 
production machine. 
FAQ 14
has more information about the OpenBSD boot process. 
Preferably use one of the four primary MBR partitions for booting OpenBSD (i.e., extended partitions may not work). 
Note that Windows 7 and Vista can resize their system partitions: go to the Control Panel, search for "partition", and 
enter the corresponding system tool. Right click on a partition, and you will notice you can shrink it. Its main limitation is 
that the Windows Exchange File can't be moved, so if you need more space, you may have to move/disable it. 
Here are several options to multibooting: