Virtual images and qemu

[deco33000 Jog]

You are right,

and I understand the paramount of virtualization. Hence my use of it now. But it doesn't change a hair of my position: I hate it but still use it.

-- 
Jog


22.09.2015, 21:29, "Wojciech Puchar" <wojtek at puchar.net>:
>>  Now it is fully working. I switched to virtualbox and chose a nat paravirt network.
>
> anyway FreeBSD 10.2 works fine under qemu - both amd64 and i386. tested.
> Anyway i never used qcow2 images, always raw.
>
>>  I really hate virtualization but will bear with it anyway.
>
> instead of hate it's better to understand.
>
> Cases where virtualization is useful:
>
> - quick test of operating system (probably your case)
> - OS/kernel development - avoids reboot as well as provide freeze and
> memory dump.
> - when you have to run more than 1 different OS on one machine. For
> example: FreeBSD server but needs to run some server software under windows. Run
> windows virtual machine on this server with this software in it.
> - preparing software disk image for different architecture (often used
> be me for FreeBSD/mips, qemu on fast PC runs faster than actual machine
> and it's easier).
> - recovery of data from disks or disk images
> - may be few more.
>
> Cases where it is not useful, or suboptimal:
>
> - running multiple images of same unix system (eg. FreeBSD, linux) on one
> computer. Use jails or similar mechanism under other unix-alike.
> - magic way to enhance security. No it isn't.
> - running windows desktops for terminal systems, one virtual machine per
> user. Suboptimal and costly, run multiple users on single windows
> computer.
> - REALLY lots of other uses just because virtualization is popular.
>
> Virtualbox is MUCH faster, qemu is much more universal. Virtualization
> always make performance overhead, and always bigger than authors claim.
> Still - it is much better running some software set even with 50% overhead, than buying
> separate machine that would be 1% utilized.