Bug 2246220

Summary: /etc/hosts uses a real domain name as an example, and not a IANA special-use domain name
Product: [Fedora] Fedora Reporter: Jeffrey Walton <noloader>
Component: setupAssignee: Martin Osvald 🛹 <mosvald>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: low Docs Contact:
Priority: unspecified    
Version: 38CC: karsten, mosvald, noloader, ovasik, pavel
Target Milestone: ---   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: setup-2.14.5-1.fc40 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2023-11-29 12:57:48 UTC Type: Bug
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:

Description Jeffrey Walton 2023-10-25 20:21:14 UTC
Hi Everyone,

This came up on a Debian mailing list, but it applies to Fedora. And perhaps Red Hat, too.

My /etc/hosts has the following entries and comments. I added the 127.0.1.1 entry manually.

   $ cat /etc/hosts
   # Loopback entries; do not change.
   # For historical reasons, localhost precedes localhost.localdomain:
   127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4
   ::1         localhost localhost.localdomain localhost6 localhost6.localdomain6

   # 127.0.1.1 is often used for the FQDN of the machine
   127.0.1.1   skylake.home.arpa skylake

   # See hosts(5) for proper format and other examples:
   # 192.168.1.10 foo.mydomain.org foo
   # 192.168.1.13 bar.mydomain.org bar

The problem is, someone owns mydomain.org. It is a real domain.

   $ whois mydomain.org | grep -E 'Name|ID'
   Domain Name: mydomain.org
   Registry Domain ID: 43938f3b31594bc394234043672173ed-LROR
   Registrar IANA ID: 228
   ...

I believe it would be much better if Fedora's /etc/hosts template used example.{com|net|org}, or home.arpa. home.arpa is a recent addition (circa 2018) to IANA's special-use domains. Cf., <https://www.iana.org/assignments/special-use-domain-names/special-use-domain-names.xhtml>.

I would also suggest to add a comment to /etc/hosts that tells a reader to check IANA's document in addition to the documentation for hosts(5).

-----

This happened on Fedora 38, x86_64, fully patched.

$ lsb_release -a
LSB Version:    :core-4.1-amd64:core-4.1-noarch
Distributor ID: Fedora
Description:    Fedora release 38 (Thirty Eight)
Release:        38
Codename:       ThirtyEight

-----

And /etc/hosts belongs to setup-2.14.3-2.fc38 on this machine.

$ dnf whatprovides /etc/hosts
setup-2.14.3-2.fc38.noarch : A set of system configuration and setup files
Repo        : @System
Matched from:
Filename    : /etc/hosts

setup-2.14.3-2.fc38.noarch : A set of system configuration and setup files
Repo        : fedora
Matched from:
Filename    : /etc/hosts

Comment 1 Martin Osvald 🛹 2023-10-26 06:56:07 UTC
Thank you for reporting this problem and your suggestions!

Indeed, example.org instead of mydomain.org should be used. I took the examples directly from the hosts man page and at that time it still contained the mydomain.org there. I can see it is no longer the case:

https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/commit/man5/hosts.5?id=2cc1bc67f9aabbfb4ae8c7f6d3082a22bddd63ab

I will fix this in the upcoming setup version.

Comment 2 Jeffrey Walton 2023-10-26 09:30:11 UTC
Thanks Martin.

In case you are interested... www.opensource.org does not seem to be at 209.237.226.90. Or not according to nslookup from the eastern US. I would probably remove www.opensource.org from the example.

Comment 3 Fedora Update System 2023-11-29 11:17:47 UTC
FEDORA-2023-77891d238e has been submitted as an update to Fedora 40. https://bodhi.fedoraproject.org/updates/FEDORA-2023-77891d238e

Comment 4 Fedora Update System 2023-11-29 12:57:48 UTC
FEDORA-2023-77891d238e has been pushed to the Fedora 40 stable repository.
If problem still persists, please make note of it in this bug report.