# Dual boot FreeBSD and OpenBSD



## BlueCoder (Apr 16, 2013)

I want to play with OpenBSD on my firewall. But I don't want to permanently replace FreeBSD instead I want to dual boot. As far as a bootloader/menu what is recommended? I really don't want to use GRUB.


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## kpa (Apr 16, 2013)

I would first try the /boot/boot0 simple boot manager that is installed with boot0cfg(8). This assuming FreeBSD uses one slice on the disk and OpenBSD another.


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## bkouhi (Apr 16, 2013)

I recommend you to use GAG boot loader. (Link)

It's lightweight, secure, easy to use, portable and...


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## BlueCoder (Apr 16, 2013)

I see OpenBSD still doesn't support GPT. Sad but I can live with it. And of course no Gjournal. Very retro.


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## Beastie (Apr 16, 2013)

If you just want to try it and your machine is powerful enough, why not run it under a virtual machine, like VirtualBox or QEMU?



			
				BlueCoder said:
			
		

> I see OpenBSD still doesn't support GPT.


I don't remember who and where, but I've seen people say GPT will be gone before MBR dies.


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## J65nko (Apr 16, 2013)

I run both OpenBSD and FreeBSD on some of my machines and I have used the boot0 bootmanager successfully for many years.

The gpart(8) EXAMPLES sections shows the command to install this very simple boot manager in a MBR partitioning scheme on disk ada0:

`# /sbin/gpart bootcode -b /boot/boot0 ada0`


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## BlueCoder (Apr 18, 2013)

I installed it and used the venerable boot0 MBR boot manager. This is on an old P4. Repartitioned and reinstalled FreeBSD first. Took a couple hours to figure out OpenBSD partitioning and only clobbered the partition table once. It's installed with a half dozen packages and doesn't even take up a full Gigabyte. I did a 30GB,30GB,80GB split. So I can NetBSD or Dragonfly to try it later. Boot0 is nice because it remember your last selection and autoboots.

I did it mainly because I wanted to try OpenBSD again(been a few years) and play around with it's new firewall features. I have to say right off the bat it feels so much faster. Web pages just seem to come up faster. I need to run some real world tests and try to figure out why.


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## sossego (Apr 19, 2013)

You can use the FreeBSD boot loader.
http://forums.freebsd.org/showthread.php?t=15294

Ta dahhhhh!
You would need to set up with an older FreeBSD install CD and then use the newer one for the system. I'm not sure if /sbin/gpart can add other types. One can ask as to how the bootloader can be reconfigured to allow booting from another partition.


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## BlueCoder (Apr 20, 2013)

My whole effort was a success. I now have a working OpenBSD firewall running DNS64 and NAT64. I kept the FreeBSD partition to do some comparison benchmarks.

My next project I think will be to install NetBSD in the spare partition and see how well both FreeBSD and OpenBSD as firewalls run under Xen! Then I'll do the benchmarking.

Are there any established programs/procedures for measuring firewall performance?

I'm thinking a simple `wget` script from my workstation.


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## sossego (Apr 20, 2013)

Be sure to use separate NICs for that project.
Congrats on getting your system set up and running.


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