network reconnection problems

[tumbletree]

Qubes OS version
4

Affected component(s) or functionality
networking

Brief summary
Upon 1. resume from suspension, 2. change of wireless network or 3. addition (then disconnection) of wired network, all qubes lose access to network. Network manager seems to be fine. Connectivity is resumed automatically after a ~10 minute period, or restart. Started in last 6 months or less, at a guess.

To Reproduce

1. Open one or more qubes, browse.
2. disturb network connections: suspend then resume; change wireless network; plug in / disconnect from wired connection.

Expected behavior
Seemless and immediate resumption of qubes' connectivity.

Actual behavior
a prolonged period of non-connectivity to the internet from any qube. Resumes in the background after ~10 minutes. Restart also works.

n.b. Qube Updater proceeded without error messages. Updater is not required to produce this behavior.

Screenshots
If applicable, add screenshots to help explain your problem.

Additional context
Add any other context about the problem here.

Solutions you've tried
Restarting network manager via sysctl command in sys-net.
Restart sys-net - can't recall if this works, but that's such a hassle (dependent vms) that a restart is easier.
On/Off wifi, networking via widget.

Only 1. restart, or 2. wait for 10 minutes (maybe more) seem to work. Note that mthod 2 might sometimes fail, but I haven't bothered to

Relevant documentation you've consulted
A list of links to the Qubes documentation (or other relevant software documentation) pages you have already consulted.

Related, non-duplicate issues
similar elements #5667

[andrewdavidwong]

Possibly related: #3008

[pabpas]

Open a terminal in sys-net and run any command with sudo: sudo ls
In my system this brings back (wired) connectivity instantly. Don't ask me why. Here an example:

Oct 12 19:47:32 sys-net kernel: Generic PHY r8169-30:00: attached PHY driver [Generic PHY] (mii_bus:phy_addr=r8169-30:00, irq=IGNORE)
Oct 12 19:47:33 sys-net kernel: r8169 0000:00:06.0 ens6: No native access to PCI extended config space, falling back to CSI
Oct 12 19:47:33 sys-net kernel: r8169 0000:00:06.0 ens6: Link is Down
Oct 12 19:47:33 sys-net kernel: IPv6: ADDRCONF(NETDEV_UP): ens6: link is not ready
Oct 12 19:49:11 sys-net kernel: r8169 0000:00:06.0 ens6: Link is Up - 1Gbps/Full - flow control rx/tx
Oct 12 19:49:11 sys-net kernel: IPv6: ADDRCONF(NETDEV_CHANGE): ens6: link becomes ready

[github-actions]

This issue is being closed because:

• This issue is on the "Release 4.0 updates" milestone.
• Qubes OS 4.0 reached EOL (end-of-life) over one year ago.
• There has not been any activity on this issue in over one year.

If anyone believes that this issue should be reopened and reassigned to an active milestone, please leave a brief comment.
(For example, if a bug still affects Qubes OS 4.1, then the comment "Affects 4.1" will suffice.)