CentOS - Jan 2014 - I want to ask about some Kernel level operations.

I want to make sure that while compiling as root nothing will break down 
inside the machine.

I want to compile software on a Xeon SERVER.
The basic issue is that there is a recommendation to not compile it as a 
root user.

I have compiled software as a root user more then once and I am not sure 
why would there is a need to run it as non-root user?

I have taken a look at the /proc/ FS but I do not see anything that can 
harm anything yet.

 From my aspect it's just background of electricity noise.

I will be happy to hear from experience of others about it.

Thanks,
Eliezer

On Thu, 02 Jan 2014 01:53:09 +0200
Eliezer Croitoru wrote:
> I have compiled software as a root user more then once and I am not sure 
> why would there is a need to run it as non-root user?
1. Bad Things?  happen sometimes.  If you are root, Worse Things? can happen
than what might happen if you are not root.

2. It's just basic common sense to use the root access to the minimum extent
possible.  (See Step 1)

3. Since it's not necessary to compile software as root -- goto Step 1.

-- 
MELVILLE THEATRE ~ Real D 3D Digital Cinema ~ www.melvilletheatre.com

On 1/1/2014 3:53 PM, Eliezer Croitoru wrote:
> I have compiled software as a root user more then once and I am not sure
> why would there is a need to run it as non-root user?
Its the principle of least privilege.

You don't need to be root to compile software, or to test software in a 
local directory, you only need root privileges to install it to a system 
directory.   When you're developing, building, testing software, there's
a very good chance of something going wrong, so if you are running as a 
non-root user, the potential damages are minimized.


-- 
john r pierce                                      37N 122W
somewhere on the middle of the left coast

On 02.Jan.2014, at 00:53, Eliezer Croitoru wrote:
> I want to make sure that while compiling as root nothing will break down 
> inside the machine.
> 
> I want to compile software on a Xeon SERVER.
> The basic issue is that there is a recommendation to not compile it as a 
> root user.
Actually I would go even further and not recommend to have a compiler
installed on a server.
> 
> I have compiled software as a root user more then once and I am not sure 
> why would there is a need to run it as non-root user?
> 
> I have taken a look at the /proc/ FS but I do not see anything that can 
> harm anything yet.
> 
> From my aspect it's just background of electricity noise.
An example:

imagine a Makefile with a clean target

$BUILDDIR=something
clean:
   rm -rf $BUILDDIR/*

a bug in the configure script could lead to an empty $BUILDDIR in the Makefile.
What do you think happens when you type

# make clean

-- 
Markus

On 1/1/2014 6:53 PM, Eliezer Croitoru wrote:
> I want to make sure that while compiling as root nothing will break down
> inside the machine.
>
> I want to compile software on a Xeon SERVER.
> The basic issue is that there is a recommendation to not compile it as a
> root user.
>
> I have compiled software as a root user more then once and I am not sure
> why would there is a need to run it as non-root user?
>
> I have taken a look at the /proc/ FS but I do not see anything that can
> harm anything yet.
>
>   From my aspect it's just background of electricity noise.
>
> I will be happy to hear from experience of others about it.
The basic issue is limiting your exposure in the case of a problem. As 
long as everything works and is programmed properly, you can do whatever 
you want as root.  But as soon as there is a problem, there can be huge 
consequences.

The root user has access to everything on the server.  So a typo in a 
program/makefile/command has the possibility of bringing down the whole 
server.  On the other hand, if you are logged in as a normal user, then 
the damage is limited to your directories.

Best practices say that you should do everything possible as a normal 
user.  Root should only be used when you must have access to something 
that the normal user doesn't.  Some distributions (like Ubuntu) even 
enforce this by not allowing root logins and forcing the user to use 
sudo for commands that require root access.

Bottom line is this:  It's your server, so use root if you want. Just be 
aware of the dangers and don't try to blame anyone other than yourself 
when a typo or misbehaving build script takes down the system.

-- 
Bowie