So, after my Windows 7 machine at work ate itself after a Windows Update. I decided to turn it into an Ubuntu 12.04 system.
But, so much for becoming Windows free. I was informed that I need a Windows machine to run vCenter on, because the shared Windows 2003 server that we had been using is going away.
So, I setup Windows 7 in VirtualBox...pretty simple. But, soon I was getting ext4 messages complaining about unaligned access for a certain inode. The VDI for the Windows 7 install.
I searched around on VDI and 4K alignment, and eventually found this:
HOWTO: Modify empty VDI for optimal alignment of Windows
Though reading further it seems to suggest that newer versions of VirtualBox get the alignment right for you....and 4.1.24 is much newer than 3.0.12 in the original post. (had opted for 4.1.24, since 4.2.6 is not recommended for BOINC Test4Theory....but 4.2.8 is out now, and it is recommended....so it'll be time to go and update all my machines, I guess. The only systems with 4.2.6 were FreeBSD, because the 4.1.24 will cause the 9.1 kernel to panic on VM exit. though don't know if 4.1.24 was bad in ports or not, had been 4.1.22 before upgrading to 9.1 -- but had to recompile the kernel modules after the upgrade so had first tried 4.1.24....)
So, I went through the HOW-TO to create an new emtpy VDI...and found that it is already 4K aligned. So, why was the VDI created through the 'New Wizard' in VirtualBox Manager not?
Anyways...I then booted gparted and copied my partitions over to the new VDI....and then had to boot the Win7 installer to fix the startup to get it to boot, and no more complaining.
Guess I'll have to remember to create VDI before creating the new VM in the future? Wonder if there are issues in other disk image formats. Wonder if ZFS would complain that my VDI isn't aligned? Wonder how to check? Though the other formats I use are either VHD or VMDK. VHD because that's what Microsoft Windows Image Backup creates, and I'm using the last one of Zen to try to recover files from.... VMDK is after an import/export of a VM or for raw zvol accesses. So, guess those aren't areas of concern for me right now.