Hitchhiker's Guide to Openbsd

partition as "Active" for booting. 
3. Format the other partition. This can be (and perhaps should be) done on the "target" OS (Windows, 
in this case). 
Note that if the other partition's type is chosen appropriately, it is possible to have OpenBSD access both 
partitions on the device. So, a Windows user could populate the FAT32 partition with MP3 files which 
could be played when they booted from the OpenBSD partition. 
14.17.3 - How do I create a bootable "Live" USB device?
It is very easy to create a bootable USB flash (or other!) drive that can be used as a "live" OpenBSD system 
without installing OpenBSD on the local hard disk of a machine. Obviously, the target machine must be bootable 
from a USB device, but the initial load can actually be done from any machine with a USB interface. 
http://www.openbsd.org/faq/faq14.html (31 of 34)9/4/2011 10:02:25 AM

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14 - Disk Setup
Some reasons you may want to do this: 
●
A portable, secure "machine" you can carry with you in your pocket. 
●
Fix problems in OpenBSD and other installs with tools that aren't available with 
bsd.rd
 
●
Evaluate hardware for OpenBSD compatibility at the point of purchase. 
●
Install machines that lack any other form of boot media. 
●
Collect 
dmesg
outputs from your friend's computers! (As OpenBSD's dmesg is useful for identifying 
hardware, this can be a good way to prep for the install of OTHER OSs on a machine -- make sure you 
have all the needed drivers before starting). 
Creating such a "live OpenBSD drive" is simple. 
●
Mount your USB drive to the machine you are installing from. 
●
Boot your favorite OpenBSD install media. 
●
Install
as normal, being careful to select your flash drive as the install target. 
●
Boot from your newly created USB device. 
That's it! 
There are some things you may want to do after the install to improve your results: 
●
Install all packages and utilities you are likely to wish to have available. 
●
Different target machines will likely have different NICs. You could create a bunch of 
hostname.if(5)
files 
in 
/etc
, each containing just 
dhcp
, for all the NICs you are likely to encounter (fxp0, re0, rl0, bge0, 
bnx0, em0, etc.) on USB-bootable machines, plus maybe sample wireless config files as well. OpenBSD 
will ignore all hostname.if(5) files for devices not present at boot time. 
●
You may wish to have a copy of the install files and maybe any desired package .tgz files so you can use 
the drive as an install media (boot bsd.rd instead of letting it boot normally). 
●
On many machines, X will "Just Work" with no config file, but you may wish to collect X config files for 
those systems that require them. 
●
Soft updates
will be something you will want to use. 
●
For maximum flexibility, you probably want to use 
i386
 rather than 
amd64
. However, if you wish to use it 
as an install media, you could have an amd64 bsd.rd and install files in addition to i386. 
●
If your target machine has an 
ahci(4)
 or SCSI interface, you will probably find your USB drive's identifier 
changing. Having multiple versions of your 
/etc/fstab
file may make this easier to "fix" (in single 
user mode). 
●
You may find it desirable to have a FAT partition on the USB drive, create it as detailed 
above
. 
●
You may wish to use 
softraid(4)
 to encrypt a data partition.