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The worst unix disaster I ever saw happened to one of my co-workers. He was working on a client machine, logged in as root because he needed to compile and inst

The worst unix disaster I ever saw happened to one of my co-workers. He was working on a client machine, logged in as root because he needed to compile and install some complicated software. As he was working, he did an ls -l /bin and copy-pasted it to a text editor so he could make sure everything was installed correctly. Unfortunately, after returning to his console, he accidentally hit paste. Most of /bin was actually symlinked somewhere else. As you know, ls shows symlinks like this: lrwxrwxrwx 1 root root 20 Apr 27 17:02 cc -> /etc/alternatives/cc Guess what happens when you paste a whole list of those into a console as root?

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talmand 12y ago
The worst unix disaster ever? Could you elaborate for non-unix people such as myself?
- smwht 12y ago
  The important character here is the '>'. This redirects output to a file and overwrites the file. The lrwxrwxrwx will only print an error, but the redirect to the target executable will erase the target. For example: $ echo "asdf" > foo $ cat foo asdf $ lrwxwrwxrwx 1 root root -> foo lrwxrwxrwx: command not found $ cat foo $ So basically, this zero'd out every executable on the system.
  - talmand 12y ago
    Yep, that's bad. Out of curiosity, what was the solution to fix all that?
    - mianosm 12y ago
      Possibly a cp or an scp from a remote system with a working set of binaries.
    - kstenerud 12y ago
      scp was in /usr/bin, so we could at least copy enough basics from another system and recover the rest from a backup. Needless to say we lost the client contract.
Tyr42 12y ago
Oh no, that redirect!
lcedp 12y ago
That's fascinating. To prevent this from happening with me, I've added the following line to my `.Xdefaults` URxvt.perl-ext: confirm-paste (I'm using `rxvt-unicode`) http://i.imgur.com/joHRXaH.png http://i.imgur.com/joHRXaH.png

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talmand 12y ago

The worst unix disaster ever? Could you elaborate for non-unix people such as myself?

smwht 12y ago
The important character here is the '>'. This redirects output to a file and overwrites the file. The lrwxrwxrwx will only print an error, but the redirect to the target executable will erase the target. For example: $ echo "asdf" > foo $ cat foo asdf $ lrwxwrwxrwx 1 root root -> foo lrwxrwxrwx: command not found $ cat foo $ So basically, this zero'd out every executable on the system.
- talmand 12y ago
  Yep, that's bad. Out of curiosity, what was the solution to fix all that?
  - mianosm 12y ago
    Possibly a cp or an scp from a remote system with a working set of binaries.
  - kstenerud 12y ago
    scp was in /usr/bin, so we could at least copy enough basics from another system and recover the rest from a backup. Needless to say we lost the client contract.

Tyr42 12y ago

Oh no, that redirect!

lcedp 12y ago

That's fascinating. To prevent this from happening with me, I've added the following line to my `.Xdefaults` URxvt.perl-ext: confirm-paste (I'm using `rxvt-unicode`) http://i.imgur.com/joHRXaH.png http://i.imgur.com/joHRXaH.png