Netbsd 4.0 domU How-to

Not a 100% straight forward to install, and there were gaps in most FAQ’s and guides I found on the internet. However collating them gave me the information i need to have a fully working Netbsd4 install in my xen enviroment.

Step 1.  (find the kernel)

If you go to their website and read the xen install guide it pretty much will tell you that you need a xen kernel (of course) which are are in the binary kernel downloads. Looking on their download pages and through mirrors would only find me a i386 kernel which is no good. Under the amd64/ folder was only their general kernels and not a dom0 or dumU kernel. A bit of googling found be a link that didn’t work, however after traversing the link i worked out that the xen kernels are under the daily builds folder (my own fault for not reading things thoroughly enough). So click here and get yourself a xen kernel — > CLICK HERE

Step 2. (create domU)

I’m assuming (never a good thing) that if you’re googling or searching for such things as a netbsd domU install then you know the basics for making a domU. Creating you domU config file is straight forward, allocate memory, a name, a disk (file or physical path) and then give it a path to the kernel. You may have noticed that there were a couple of xen kernels on the ftp site, two are required:


To begin with use the install one (pointing out the obvious here) this contains a ramdisk which will configure your hardware (such as network cards) and allow you to do a step by step install. Be mindful of the path used in the ftp/http install as the default one is incorrect. Once the installation has completed *DONT REBOOT*

Step 3. (Fix domU)

Once installation takes you back to the main install screen, open the utilities and drop to the shell /bin/sh. The xen device files need moving over to the actual file system otherwise on reboot it wont find any disks, which can be irritating as it took me some messing around until i found this solution.

mount /dev/xbd0a /mnt 
cp -pR /dev/rxbd* /mnt/dev 
cp -pR /dev/xbd* /mnt/dev 
halt -p

This will mean that when you reboot the system will see the xen devices and actually have a disk to boot from. Once this is done and the system is halted you probably will need to control-5 out and do an xm destroy on the netbsd domU (doesn’t matter as the system is halted). The final step is to change the kernel in your domU config file from the install one over to the actual domU kernel.

Step 4. (boot your working netbsd domU)

xm create -c <your_config>    

Enjoy… oh and cheers for asistance

Netbsd 64bit domU

I’ve been wanting a bsd domU since i managed to originally get my xen server up and running, again googling the great wide web revealed past threads on forums and dead links. The effort to port the freeBSD kernel has been all but abandoned, and openBSD doesn’t appear to be moving toward that at all. So I looked into netBSD with their motto “Of course it runs NetBSD.”  surely I couldn’t go wrong. However when I was originally looking in Nov ’07 there was only a 32bit domU kernel and my xen domain is all 64bit so unless i went down the hvm route (which i didn’t) then that was that.

Yesterday I noticed that netbsd has been updated late december, and after a bit of searching found a note in the changelog saying that there was a 64bit kernel now for xen. However it’s hidden in the various depths of netbsd’s ftp site, which took a considerable bit of finding. However here is proof –>


Reclaiming space and expanding metadevices

example scenario:

/home is at 100%

/pointless is 0%

Both of which are meta softpartitions e.g. d10 for /home and d20 for /pointless. In our example we are going to increase the size of /home using the space utilised in /pointless (as it’s pointless and not needed 🙂 )

1. unmount /pointless

2. metaclear d20 (remove the meta partition)

3. metattach d10 10g   (g = gig, m =meg) (also 10g was the size occupied by d20)

4. growfs -M /home /dev/md/rdsk/d10

A df -h on /home now will show you that it has grown by the 10Gb, also no downtime is required for this operation.

Like oh WOW, totally !

Aside from the funny requirements for memory with the java inital check (1gb for install) 512 is fine afterwards. Creating an nv81 domU is very straight forward, and seems to have no obvious bugs.

Solaris cluster is a different matter altogether, two pretty much identical nodes using remote installation results in absolute failure. Doing the remote installation from node a, will configure node b and reboot it and wait for it to come back up waiting to create the cluster. So node b on reboot does this..

Started domain solaris-b 
                        Loading kmdb... 
v3.1.1 chgset 'unavailable' 
SunOS Release 5.11 Version snv_81 64-bit 
Copyright 1983-2007 Sun Microsystems, Inc.  All rights reserved. 
Use is subject to license terms.
panic[cpu0]/thread=fffffffffbc3e9a0: vmem_hash_delete
(ffffff0083809000, fffffffe00000000, 0): bad free

Cancelled the install on node a, and thought i’d attempt a single node cluster install to see if that would result in something different….. which it didn’t 🙁

For anyone who’s a tad bored stack traces are available here

My next plan involves skipping xen kernels and using hvm and solaris 10 (release) and attempting that. However in hindsight i’ve just remembere that hvm will only emulate 32bit and sun cluster 3.2 requires 64 bits. FAIL!

On the plus side skins series 2 starts soon.

Release 81

No sign of release 79 or 80… so they’ve skipped them.

Trying to do an install now, it appears that previous releases would install with 512Mb whereas this one will have you staring at

Setting up Java. Please wait…

Which will stay on your screen until you die of old age, or leave the house, which ever the more likely.

 So I’ve created my template domain and will be starting attempt 99,9999,9999999,9999999 to build a cluster from virtual machines.

P.s. sys-unconfig is pretty useful.. forgotten about this one from starting afresh !


Tomorrow I take flight to Canada !! Banff to be precice, The weather is looking mighty cold, going to go as low as -20c so i’ve been getting in as much practice as I can as I don’t want to die on a mountain 🙁 I’ve even been out and purchased  a snowboard (below) which I aim to thrash down the mountain sides in the coming days. Going to be good!

My Snowboard


My New years resolution was to quit drinking, however a 30th birthday party one week in to the new year kind of made a mess of it. Drinking until 3-4am isn’t in keeping with my original resolution, but nevermind noone ever really manages to keep up with there resolutions. The next day wondering around tescos (with stinking headache) I noticed this strange bottle on the shelves.


The tag line “Hypertonic for alcohol consumers” made me curious, so I picked one up to see if it did help at all. After we got back and put the shopping into various cupboards etc… I tried this drink…


The aftertaste of rotting vomit really didn’t do it for me, Kim hated it as well so majority was that i’ll stick to water.

The Desk

I decided to re-0rganise my desk recently, so that it’s a bit easier to get to bits and bobs. However here is living proof of the working output from my ‘modified’ poweredge machine -> how-to. The silver fronted machine is the server, quad core with 4Gb of ram which is next my ‘workstation’ which is the dual core xeon with another 4Gb of ram. All in all my set up is nearly put together, under the desk which you can’t see is the gigabit switch and the NAS.

The Desk

The NAS is an Maxtor MSS II, which i’m part way through botching in order to make it more useful. The MSS II is alright but it’s really designed for small businesses that generally don’t have an IT department, just one of those members of staff who buys some daft magazine every now and then, but assumes he knows everything. With that in mind the NAS is a simple little linux box with a web front end and samba running on it. This would be alright in a simple office with a couple of xp/vista boxes but start to mix OS’s and utilise the device a little bit more than it likes and thinks will break quite quickly. The people from are always coming up with new ideas and bits of software and it’s looking like NFS and iSCSI may be not too far away.