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Description of problem:

 After reconnecting a device, the order of name servers in resolv.conf is wrong

 https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/issues/1331

Version-Release number of selected component (if applicable):

 All NM versions from 1.32 to 1.43.10.

How reproducible:
 100%

Steps to Reproduce:
 nmcli connection add type dummy con-name dummy-dummy1 ifname dummy1 \
                      ip4 172.25.1.1/24 gw4 172.25.1.254 ipv4.dns 172.25.1.53 \
                      autoconnect no ipv4.route-metric 100 ipv6.method disabled
 nmcli connection add type dummy con-name dummy-dummy2 ifname dummy2 \
                      ip4 172.25.2.1/24 gw4 172.25.2.254 ipv4.dns 172.25.2.53 \
                      autoconnect no ipv4.route-metric 200 ipv6.method disabled

 nmcli connection up dummy-dummy1
 nmcli connection up dummy-dummy2

 # now dummy1 is best

 nmcli connection down dummy-dummy1

 # now dummy2 is best

 nmcli connection up dummy-dummy1

 # due to the bug, now both dummy1 and dummy2 are best

 cat /etc/resolv.conf

Actual results:

 The first name server is 172.25.2.53 in resolv.conf

Expected results:

 The first name server is 172.25.1.53 because dummy1 has the best default route

Additional info:

 Upstream fix: https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/1683

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 (NetworkManager 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-2023:6585