OpenBSD Journal

Bootable OpenBSD CDROM

Contributed by jose on from the ramdisk-and-mfs dept.

Jason Murray asks:
"I've seen an old (June 2001) Daemon News article on how to build a bootable OpenBSD CDROM, but I was wondering if there is anything more current ( )

The reason I ask is because I am buying a 802.11 card and want to build a wardriving laptop. However, since the only laptop I have is the my work laptop, and I can't dual boot on it, I thought it would be nice to be able to have everything on a bootable CDROM."

I have seen some instructions before, including this recent article here on deadly which included Francisco's how-to, and nothing detailed for custom live filesystem cdroms. I have built some of my own using vnconfig and a ramdisk kernel and the like, but I don't really have a recipe handy (or available to share). Anyone have any other recipes they can share?
Update Since we ran this story a few weeks ago, I'm seeking more indepth discussions and ideas that people have developed recently.

(Comments are closed)

  1. By Anonymous Coward () on

    I am unsure how much different OpenBSD is from Linux concerning the boot process - I guess it is rather different - but nevertheless, perhaps the The Linux Bootdisk HOWTO helps you a bit.
    Good luck!

  2. By abcd () on

    Grab the filesystem of the 3.2 dir off of a FTP (when it comes out that is), feel free to subtract the arch's that you wont need.

    Use the cd boot image (2.8MB) as the boot image for the ISO disc you create. CDRWin can do this on Windows, and the normal stuff on Nix/Nux..

    Burn and boot ;)

  3. By Anonymous Coward () on

    for wardriving use cdrom32.fs to make a bootable cd, and choose 'shell' at the prompt. i can't remember if wicontrol/ancontrol is in the ramdisk image, though. if it isn't just place those two files on the cd as well. you could use that method for all the files:
    tar -zxvpf *32.tgz -C /openbsd/
    cp cdrom32.fs /openbsd/
    make and burn bootable cd image from the /openbsd/ dir, and you're set. you wont have all devices and your / dir will be kinda tight, but it will be enough to wardrive. RAMDISK_CD has msdosfs compiled in so you may be able to mount your preexisting partitions w/ no change. otherwise you may want to compile in mfs support so you can mount a partition to safe data on.

    you may find my howto useful for ideas. it outlines making a bootable cd which results in a system running only in ram.

    1. By Anonymous Coward () on

      gee, i didnt read all the way through the original post. oops.

    2. By Anonymous Coward () on

      Full wireless support is even included on the floppy boot disk. It's awesome, can do a wireless ftp install on the fly!

  4. By Anonymous Coward () on

    buy a cd to support the project

  5. By ViPER () on

    I'll give you a hint how to make a bootable cd,
    still you should order the original 3pack cd.
    Even the stickers are worth the buck.
    (Chicks dig them)

    download the dir
    mkisofs -b "i386/cdrom31.fs -v -allow-lowercase -iso-level 2 -o openbsd.iso -log-file=/tmp/log.txt ./


  6. By grey () on

    You might want to look at Chris Cappucio's soekris config scripts for some ideas - albeit it's not full read only FS geared, but a lot of it is (since you don't want to do too many r+w's on a CF card).

    Really any of the past mailing list discussions talking about this subject should help.

    Similarly check:

    (a FreeBSD approach that still might be helpful)
    (doesn't list instructions, nor seems to be up - but google cache reveals a similar project)

    If you're just looking for some info on how to make a bootable install CD - then the shockley instructions should be sufficient (though they kinda suck as they use a cygwin+EasyCD environment as an assumption when for Windows, just Nero or something would be simpler).

    This question seems to come up over and over again - I don't think it's necessarily appropriate for a FAQ, but if someone who does this regularly would just sit down and right up a document to put someplace permenant it would hopefully cut down some of this repetition.

  7. By Anonymous Coward () on

    Damn guys... How often are you going to be running this story?

    Here's the answer now, and what it will be the next time you ask... It's trivial to make a 'live' OpenBSD. However, nobody cares.

    Hard Drives are dirt cheap, and flash isn't too expensive. CDs are slow, and you can't write to them. Nobody wants to waste their time with such a useless novelty item.

    If you can't figure out how to install OpenBSD on some decent media, then make a bootable CD yourself, and quit complaining.

    1. By Anonymous Coward () on

      the point of this is to run it on a read-only filesystem.

      1. By Anonymous Coward () on

        And dropping trojans onto a read-only file system is quite a challenge. :>

      2. By Anonymous Coward () on

        You seem to be making it up as you go... Acroding to the story, the point is that the guy can't boot OpenBSD from anything other than CD.

        since the only laptop I have is the my work laptop, and I can't dual boot on it, I thought it would be nice to be able to have everything on a bootable CDROM."

        1. By Jason Murray () on

          That guy might just be reading the responses.

          The reason I can't dual boot is not that I can't figure out how to install OBSD (I've been running it at home since 2.5), but that the company policy is that we run Windows on our laptops. Since a lot of good tools are available for freenixes that aren't available for Windows, and I happen to prefer OBSD I would like to be able to use it for my work. The only way for me to do this is to have a bootable CD.

          A read only filesystem is a fringe benefit for me in this case.

          1. By Anonymous Coward () on

            the company policy is that we run Windows on our laptops.

            is it ok to install VMware?

            1. By Jason Murray () on

              Yes, but I've been told by others who've tried it that VMWare won't let a guest OS access the card at a low enough level to allow some of the tools we want to run.

              1. By Anonymous Coward () on

                VMWare won't let a guest OS access the card at a low enough level

                that sucks. wish i had a laptop capable of running vmware to work on.

                does VirtualPC offer any better support for that?

              2. By Scooby () on

                I've run Ethereal and tcpdump without issue under VMware, how low a level are you trying to go?

          2. By Anonymous Coward () on

            "...the company policy is that we run Windows on our laptops."

            What is the company policy on wardriving with coporate assets?

            1. By Jason Murray () on

              Smart Ass.

              Since I work in the security practice of a consulting company, wardriving and pentesting is part of my job.

  8. By Anonymous Coward () on

    Freebsd has a port called livecd.
    It would realy like to see it in openbsd.
    Lookat and

  9. By Anonymous Coward () on

    hi, i'm working on another howto. it's almost done, needs revising and some references added, and will probably change after it's done due to the nature of such things, but here you go:
    How to Make a Bootable, Full System OpenBSD CDROM

    This document will walk you through the steps necessary to create a bootable cd containing a full OpenBSD install.

  10. By Jeff () on

    Well, it's unlikely anyone will hit this story unless they hit Google, but as of 7/23/2003 some effective directions for creating a livecd OpenBSD image are at .


    1. By David () on

      thanks jeff, I hit Google :)
      (but the page seems down)


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