What is on Your Mind?

A few years ago I had a very functional linux from scratch machine built. I had Xfce up and running as well as all of my applications. I was installing the proprietary AIM client and went to clean up after the installation when I did this:

Code:

# rm -rf *
# pwd
/usr/lib

The chmod one is good - the chown one is also good (for different reasons)

I remember a few years ago (I wasn't a sysadmin) I noticed the passwd file had 666 permissions (how appropriate). Only my honesty prevented me changing my uid to 0 (honest).

Everyone's done the rm -rf one, surely!
(it was a long time ago, but went something like this (fortunately at home)..)

Code:

cd /u01/data/backup
ls -l
X=$PWD
cd /u02/data
ls -l
(looks good)
rm -rf $x/*

I don't ever remember doing that twice! As root, if I did it now, I'd just clear my desk and leave my badge at the front desk on the way out!

A few years ago I made a chown -R mistake. I found out that the hard way that chown -R user:group .* (the solaris version anyway) will see .. as part of the recursion and change ownership of all files and directories (and everything in them) one level above the directory you are in. I did this in my home directory on the NFS server that shared them out. I ended up owning everyones files...

Another mistake I have made is getting distracted and doing shutdown -i6 -y -g0 on a server instead of my workstation. I consider myself lucky to have never screwed up a production machine bad enough to get me in trouble. My advice to anyone reading this trying to get their foot in the door and get a UNIX job is to download a free UNIX and make your mistakes at home. I also recommend aliasing commands like rm -rf to rm -rif. Especially for root.

On Linux it's pretty simple to do killall commandname instead of killing things by pid all the time, but it can be a dangerous habit to get into. This command exists on Solaris and, I think, several other flavors, but has a completely different and absolutely literal meaning. It needs no arguments.

---------- Post updated at 03:06 PM ---------- Previous update was at 02:57 PM ----------

It's smart enough to reject "." and so not loop forever through the same directory, but nobody thought to reject "..". How odd.

which you will never get the files after this... will you???

Code:

mv /home/yourhomedirectory/* /dev/null

/dev/null doesn't work that way. You cannot move files into something that's not a directory. And if ~/* turns out to be one file, it will still complain that you cannot remove /dev/null to replace it unless you're root.

That said, replacing /dev/null with an ordinary file might mess up any number of things...

I've just decided. The most deadly command is vi!

I made some changes to inittab on a "new" Solaris Netra and the server wouldn't boot (obviously I typed something wrong!). I spent the last I'm-too-embarrased-to-say-how-many hours fixing it!