On 10/27/23 10:11, Pocket wrote:
Sent from my iPad
On Oct 27, 2023, at 10:00 AM, Andrew M.A. Cater <amaca...@einval.com>
wrote:
On Fri, Oct 27, 2023 at 09:30:09AM -0400, Pocket wrote:
Sent from my iPad
On Oct 27, 2023, at 9:05 AM, Greg Wooledge <g...@wooledge.org> wrote:
On Fri, Oct 27, 2023 at 07:59:00AM -0400, Pocket wrote:
On 10/27/23 07:50, Greg Wooledge wrote:
On Fri, Oct 27, 2023 at 07:29:20AM -0400, Pocket wrote:
/etc/hosts
If you're using short-form hostnames like this:
unicorn:~$ hostname
unicorn
then yeah, that's all you need. If you're using long-form hostnames
(with dots in them), then you also need to configure /etc/hostname.
hostnamectl set-hostname is the command to do it - and will survive a
reboot.
This is I believe, the first time I've heard of this command, why the
big secrecy in all correspondence to to date in this thread.
W/o issueing any "modify it commands:
gene@coyote:/etc$ hostnamectl
Static hostname: coyote.home.arpa
Transient hostname: coyote
Icon name: computer-desktop
Chassis: desktop 🖥
Machine ID: 7e8cfc91c7f24faa835e71ef5583898c
Boot ID: 1c90524af6584a36b93398f51e7427fa
Operating System: Debian GNU/Linux 12 (bookworm)
Kernel: Linux 6.1.0-13-rt-amd64
Architecture: x86-64
Hardware Vendor: ASUSTeK COMPUTER INC.
Hardware Model: PRIME Z370-A II
Firmware Version: 0801
gene@coyote:/etc$ hostname
coyote.home.arpa
gene@coyote:/etc$ dnsdomainname
home.arpa
gene@coyote:/etc$
Which is all correct. But dnsdomainname WILL return (none) after the
next reboot. Why, what have I not dome correctly?
Andy
From the man page
THE FQDN
The FQDN (Fully Qualified Domain Name) of the system is the name that
the *resolver <https://manpages.org/resolver/3>*(3) returns for the host
name, such as, /ursula.example.com/. It is usually the hostname followed
by the DNS domain name (the part after the first dot). You can check the
FQDN using *hostname --fqdn* or the domain name using *dnsdomainname*.
You cannot change the FQDN with *hostname* or *dnsdomainname*.
The recommended method of setting the FQDN is to make the hostname be an
alias for the fully qualified name using //etc/hosts/, DNS, or NIS. For
example, if the hostname was "ursula", one might have a line in
//etc/hosts/ which reads
127.0.1.1 ursula.example.com ursula
Technically: The FQDN is the name *getaddrinfo
<https://manpages.org/getaddrinfo/3>*(3) returns for the host name
returned by*gethostname <https://manpages.org/gethostname/2>*(2). The
DNS domain name is the part after the first dot.
Therefore it depends on the configuration of the resolver (usually in
//etc/host.conf/) how you can change it. Usually the hosts file is
parsed before DNS or NIS, so it is most common to change the FQDN in
//etc/hosts/.
If a machine has multiple network interfaces/addresses or is used in a
mobile environment, then it may either have multiple FQDNs/domain names
or none at all. Therefore avoid using*hostname --fqdn*, *hostname
--domain* and *dnsdomainname*. *hostname --ip-address* is subject to the
same limitations so it should be avoided as well.
Cheers, Gene Heskett.
--
"There are four boxes to be used in defense of liberty:
soap, ballot, jury, and ammo. Please use in that order."
-Ed Howdershelt (Author, 1940)
If we desire respect for the law, we must first make the law respectable.
- Louis D. Brandeis
