3 - Creating bootable OpenBSD install media

As examples, we will look at the installation images available for the i386 and sparc platforms.
The i386 platform has six separate installation disk images to choose from:

• floppy41.fs (Desktop PC) supports many PCI and ISA NICs, IDE and simple SCSI adapters and some PCMCIA support. Most users will use this image if booting from a floppy
• floppyB41.fs (Servers) supports many RAID controllers, and some of the less common SCSI adapters. However, support for many standard SCSI adapters and many EISA and ISA NICS has been removed.
• floppyC41.fs (Laptops) supports the CardBus and PCMCIA devices found in many laptops.
• cdrom41.fs is, in effect a combination of all three boot disks. It can be used to make a bootable 2.88M floppy, or more commonly, as a boot image for a custom recordable CD.
• cd41.iso is an ISO9660 image that can be used to create a bootable CD with most popular CD-ROM creation software on most platforms. This image has the widest selection of drivers, and is usually the recommended choice if your hardware can boot from a CDROM.
• cdemu41.iso is an ISO9660 image, using "floppy emulation" booting, using the 2.88M image, cdrom41.fs. It is hoped that few people will need this image -- most people will use cd41.iso, only use cdemu41.iso if cd41.iso doesn't work for you.
Yes, there may be situations where one install disk is required to support your SCSI adapter and another disk is required to support your network adapter. Fortunately, this is a rare event, and can usually be worked around.
The sparc platform has three separate installation disk images to choose from:
• floppy41.fs: Supports systems with a floppy disk.
• cd41.iso An ISO image usable to make your own CD for booting SPARC systems with a CD-ROM.
• miniroot41.fs Can be written to a swap partition and booted.

3.1 - Creating floppies on Unix

To create a formatted floppy, use the fdformat(1) command to both format and check for bad sectors.

# fdformat /dev/rfd0c
Format 1440K floppy `/dev/rfd0c'? (y/n): y
Processing VVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVVV done.

If your output is like the above example, then the disk is OK. However, if you do not see ALL "V"'s then the disk is most likely bad, and you should try a new one.
Note that some Unix-like systems have different commands for formatting floppies. Refer to your system's documentation for the exact procedure.
Once you have a clean, formatted floppy it is time to write the installation image to floppy. For this, you can use the dd(1) utility. An example usage of dd(1) is below:

# dd if=floppy41.fs of=/dev/rfd0c bs=32k
Once the image is written, check to make sure that the copied image is the same as the original with the cmp(1) command. If the diskette is identical to the image, you will just see another prompt.
# cmp /dev/rfd0c floppy41.fs

3.2 - Creating floppies on Windows or DOS


This section describes how to write the installation images to floppy disk under Windows or DOS. You can get the tools mentioned below from the tools directory on any of the FTP mirrors, or from the 4.1/tools directory on CD1 of the OpenBSD CD set.
To prepare a floppy in MS-DOS or Windows, first use the native formatting tools to format the disk.
To write the installation image to the prepared floppy you can use rawrite, fdimage, or ntrw. rawrite will not work on Windows NT, 2000 or XP.
Note that FDIMAGE.EXE and RAWRITE.EXE are both MS-DOS applications, and thus are limited to MS-DOS's "8.3" file naming convention. As floppyB41.fs and floppyC41.fs have longer file names, you will have to find out how your system stored the file in "8.3 format" before using FDIMAGE.EXE or RAWRITE.EXE to make your boot floppies.
Example usage of rawrite:

C:\> rawrite
RaWrite 1.2 - Write disk file to raw floppy diskette

Enter source file name: floppy41.fs
Enter destination drive: a
Please insert a formatted diskette into drive A: and press -ENTER- : Enter

Example usage of fdimage:
C:\> fdimage -q floppy41.fs a:

Example usage of ntrw:
C:\> ntrw floppy41.fs a:
3.5", 1.44MB, 512 bytes/sector
bufsize is 9216
1474560 bytes written

3.3 - Making a CD-ROM

You can create a CD-ROM using either the cd41.iso file or, in the case of the i386 and amd64 platforms, you can also use the cdrom41.fs as the bootable floppy image that is used to boot an i386 system from CD-ROM. The exact details here are left to the reader to determine with the tools they have at their disposal.
Some of the tools in OpenBSD are:
• mkhybrid(8)
• cdrecord, part of the cdrtools collection in the OpenBSD Packages and Ports System.
• cdio(1)'s "track at once" (tao) recording option.

NEXT... 4 - Booting OpenBSD install media