Question: If you are root, and you issue 

```
rm -rf / 

```

Then how far can the command go? Can you recover data from this kind of an action? Even after the binaries are gone, would the running processes still be active? What would it take to make the same physical machine boot again? What files would you need to restore to make this happen?

I could try this on a VM and see, but I want to know the rationale behind what to expect if I do this.

Answer: 
This command does nothing, at least on the OS I use (Solaris) with which this security feature was first implemented:

```
# rm -rf /
rm of / is not allowed

```

On other \*nix, especially the Linux family, if a recent enough Gnu rm is provided, you would need to add the `--no-preserve-root` option to enable the command to complete (or at least start).

How far would this command go is undefined. It depends on plenty of more or less unpredictable events. Generally, processes can run even after their binaries have been removed.
As some people said, you can still use `sudo rm -rf /*` to remove anything. Without the asterisk works on the OS X too. Someone has made a footage on destroying OS X Yosemite like this, and I am sure that Linux based OS will experience much the same.

Things slowly begin getting irresponsive. I don't think that everything got deleted, as the terminal froze while the process was happening, but it was enough to freeze the whole thing and do a force restart.

Attempting to reboot causes a single-user mode like boot screen with errors.