I had to set up a virtual machine on one of the Ubuntu boxes today. I heard good things about Virtualbox so I decided to give it a shot – especially since it’s distributed under GPL, it can can be installed directly via apt by simply adding this line to your sources-list:
deb http://www.virtualbox.org/debian dapper non-free
You will need to add their public key before you install.
During the installation Virtualbox creates a user group called vboxusers. To run emulation you need to be a member of that group. So what did I do? I decided to quickly add myself into the group:
sudo usermod -Gvboxusers username
I happily typed in the password, and hit enter, and decided to log out to make the change go into effect. Only halfway through the log in process I realized what I just did. I forgot -a.
Yep. I just removed myself from all the groups except for vboxusers. Brilliant! I absolutely hate when I do stupid shit like that. It’s not like this was hard to fix – I just didn’t remember of the top of my head what groups I was supposed to belong to. Of course since I was no longer part of the sudo and admin groups I could no longer sudo. Luckily enough, back in the day I decided to enable the root password. So I was able to su to become root, and then usermod myself to admin, and bunch of other groups I needed like audio, video, tty, lp and etc… I wonder what would happen if I did this on a default Ubuntu box without root account. I wonder if I would be able to recover from this that easily.
[tags]ubuntu, linux, usermod, groups, vboxusers, virtualbox[/tags]
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As I’ve written on my site, you can recover from this sort of thing fairly easily, whether or not you’ve set the root password. (Unless you’ve set and forgotten the root password, at which point you can still recover, but it’s more work.)
DOH! I hate when that happens! I once broke a 2 terrabyte volume because of my “cleverness”. Good thing that is all you did!
Thanks for the tip John!
Craig – I know – it’s so easy to fuck up the system with a simple typo when you’re root. It’s funny how many unix commands have some sort of “dry run” or “print only” option – and yet, I never ever have enough common sense to use them. :P
I think Ubuntu and Debian both have the eaisier to use ‘adduser’ command. To add yourself to a new group you would just use
sudo adduser jdoe groupx.Oh crap. I totally forgot about adduser. And there is no annoying -a in that command to ruin my day. :P
Thanks!
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eh, yeah, this is why I always use “gpasswd -a username groupname” now
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