Re: hostname

[Greg Wooledge <wooledg@eeg.ccf.org>]

On Thu, Feb 15, 2018 at 01:40:17PM -0000, bolakim53@mail2tor.com wrote:
> hostname & network
> 
> 	is my hostname transmitted as soon as i am connected ?

If you use a DHCP client, then probably it is sent by the DHCP client
to the DHCP server whenever it's time to get a new IP address.  This
will occur when you boot, and whenever your IP address lease expires.
The lease expiration is determined by the DHCP server.

Counter-question: why do you *care*?  Most DHCP servers just ignore
the hostname that you send to them.  A few will put it into a local
DNS server domain, but that usually requires special configuration
on your part ("you" being the person who is setting up the DHCP and
DNS servers, not the person booting the workstation).

If you are operating under the assumption that your hostname is being
broadcast to the entire network so that your peers can open your
shares, well, that's not a thing in Linux-world.  That's only a thing
in Windows-world.

Linux/Unix hostname resolution is only done by consulting respected
services, not by everyone announcing themselves in broadcast mode.

> 	* debian 9 is dedicated to ian murdock and i wonder why they (dev) have
> not set (default) it as hostname.

"debian" is the default hostname during installation, IIRC.

> 	is a linux-hostname like a windows-code ?

... no?  I don't know what a "windows-code" is, so I am just going to
assume the answer is "no".

See above for a comparison of Linux/Unix DNS lookups with Windows-style
broadcast announcements.

> 	* a free replacement ?

What?

> 	do i need a hostname ?

Yes.

> 	* debian does not install without & "space" is not accepted.

Then make something up.  Try "debian".  Or "linux".  Or "mycomputer".

Later, once you understand how a local network works, you can come
up with a theme.  Or some convention that lets you identify the
computer by its name.  The name that you have chosen.

> 	what is the hostname the more used on the net ?

When you have a network of dozens of workstations and you're using
ssh to connect from one to another, the hostname lets you keep track
of *where you are*.

When you have a network of dozens of workstations and one of your users
reports a problem, the hostname lets them tell you which computer is
having the problem, so you know where to login to fix it (or where to
go in person if the problem can't be resolved by ssh login).

> 	* i did not find a map, a table about that.

What?

> 	does it provide more anonymity to choose it ?

No.  It is not about anonymity.  Why...?

> 	* is it not hidden or encrypted ?

What?

> 	should a 'hostnamechanger' be a good idea as foss-privacy tool ?

What the actual fuck?

Are you trying to do something illegal and trying to HIDE it?

Is that why you're asking this crap?  Because you think that your
choice of hostname could help someone track you down to arrest you
for your illegal activities?

> 	*it could take the last connected on a wifi-spot or the more common, a
> doublon of a registered user.

You are a very warped person.  I suspect prolonged exposure to Windows.

My recommended course of treatment: stop using Windows, and start
reading about how real computers work.

> ~$ hostname
> ~$ hostnamectl
> ~$ hostname --fqd
> 
> tia.

No idea what you are even talking about here.

> 	*it could take the last connected on a wifi-spot

Oh god, you're a MOBILE user.  Laptops or something.  You've probably
never even *used* a desktop PC/workstation.  You have no understanding
of the way local area networks work because you've never BEEN ON ONE,
and you probably never will be.  The concept of computers being in
fixed locations with fixed names so that you can, y'know, FIX them, is
probably completely alien to you.

And I bet you don't care.  And I bet you think I'm some kind of fossil.

I despair for humanity.