Bug 2059655

Summary:	Allowing arbitrary static DNS configuration
Product:	Red Hat Enterprise Linux 9	Reporter:	Gris Ge <fge>
Component:	nmstate	Assignee:	Gris Ge <fge>
Status:	CLOSED ERRATA	QA Contact:	Mingyu Shi <mshi>
Severity:	medium	Docs Contact:
Priority:	medium
Version:	9.1	CC:	ferferna, jiji, jishi, network-qe, phoracek, sfaye, till
Target Milestone:	rc	Keywords:	Triaged
Target Release:	9.2
Hardware:	x86_64
OS:	Linux
Whiteboard:
Fixed In Version:	nmstate-2.2.5-1.el9	Doc Type:	Release Note
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2023-05-09 07:30:59 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:
Bug Depends On:	2060905, 2073512
Bug Blocks:

Description Gris Ge 2022-03-01 16:13:59 UTC

Description of problem:

Currently, nmstate has limitation on DNS configuration:
https://nmstate.io/devel/api.html#dns-client-configuration

which require user to defined auto-dns:false or static gateway.

This has been cause a lot problem of CNV:

https://bugzilla.redhat.com/show_bug.cgi?id=2049949
https://bugzilla.redhat.com/show_bug.cgi?id=1939557
https://bugzilla.redhat.com/show_bug.cgi?id=1926143


Version-Release number of selected component (if applicable):
nmstate-1.2.1-1.el8

How reproducible:
100%

Steps to Reproduce:
1. Changed the static DNS configuration without static gateway or auto-dns: false.
2.
3.

Actual results:

Nmstate complaining about not find suitable interface for static DNS.


Expected results:

Nmstate apply the static DNS to /etc/resolv.conf as desired.

Additional info:

Comment 1 Mingyu Shi 2022-03-03 09:44:05 UTC

Hi Gris, 

I have 2 questions:
1. Where does nmstate store the DNS in? If still stores in an NM connection:
2. Will nmstate set auto-dns to false if DHCP is enabled?

Thank you

Comment 2 Gris Ge 2022-03-04 13:48:31 UTC

Hi Mingyu,

NetworkManager will support loopback interface, in its connection, we can define DNS as loopback interface always has IP enabled.
We just set the loopback connection with highest DNS priority, so other connection's DNS will append after the loopback/global one.

Comment 4 Gris Ge 2022-06-21 04:29:52 UTC

Hi Petr,

Can I change this RFE to 9.1 or 9.2?

Comment 5 Petr Horáček 2022-06-21 11:29:10 UTC

Absolutely. We won't be consuming 9.1.

Comment 9 Gris Ge 2023-01-18 10:43:00 UTC

Patch posted to upstream: https://github.com/nmstate/nmstate/pull/2198


With this patch, we are using NetworkManager global DNS API as fallback method to
apply the desired DNS servers. When storing DNS to NetworkManager via global dns API, 
this will cause _all__ interface level DNS settings been ignored.

This will not be used for `gen_conf` mode. User still get error when not
able to store DNS into interface profile


To test this, you may use this YAML which was not supported before this patch:

```yml
---
dns-resolver:
  config:
    search:
    - example.com
    - example.org
    server:
    - 2001:4860:4860::8888
    - 8.8.8.8
    - 2606:4700:4700::1111
    - 8.8.4.4
```

Unlike DNS stored in interface profile, this DNS configuration is stored at /var/lib/NetworkManager/NetworkManager-intern.conf

Of course, when you change DNS which could be stored in interface, nmstate will purge global DNS config and
use iface profile instead.

Comment 13 Mingyu Shi 2023-02-13 07:48:33 UTC

Verified with:
nmstate-2.2.5-1.el9.x86_64
nispor-1.2.9-1.el9.x86_64
NetworkManager-1.41.90-1.el9.x86_64

Comment 15 errata-xmlrpc 2023-05-09 07:30:59 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory (nmstate bug fix and enhancement update), and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHBA-2023:2190