Re: [PLUG] Kubuntu 22.04 loses network connectivity spontaneously

On Tue, Apr 26, 2022 at 12:34 AM Rich Mingin (PLUG) <plug@frags.us> wrote:

Very odd. The Intel gig drivers are generally well behaved and well tested. I'm not sure what's most likely at this point, maybe bad firmware/power management options.

On Mon, Apr 25, 2022 at 17:14 K.S. Bhaskar via plug <plug@lists.phillylinux.org> wrote:
Rich -

I installed Fedora 35 on yet another partition, and the network remains up on Fedora. This is what Fedora's lshw says is the NIC:

*-network
description: Ethernet interface
product: Ethernet Connection (2) I219-V
vendor: Intel Corporation
physical id: 1f.6
bus info: pci@0000:00:1f.6
logical name: enp0s31f6
version: 00
serial: 70:85:c2:38:ed:51
size: 1Gbit/s
capacity: 1Gbit/s
width: 32 bits
clock: 33MHz
capabilities: pm msi bus_master cap_list ethernet physical tp 10bt 10bt-fd 100bt 100bt-fd 1000bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=e1000e driverversion=5.17.4-200.fc35.x86_64 duplex=full firmware=0.2-4 ip=<IPv4 ADDRESS> latency=0 link=yes multicast=yes port=twisted pair speed=1Gbit/s
resources: irq:144 memory:df200000-df21ffff

Ubuntu 22.04 is really our preferred OS distro for this machine. Thank you.

Regards
- Bhaskar

On Mon, Apr 25, 2022 at 1:37 PM Rich Mingin (PLUG) <plug@frags.us> wrote:
Apologies, originally replied to the wrong person. What nic is it? There are no documented universal issues with that part of the network stack, making me think it’s likely device specific. Knowing what device that is will help troubleshoot.

Running system level tests and looping shell scripts to tell you what you already know (nic goes away, comes back, seems related to idle/sleep/low power, but unclear how exactly) doesn’t seem likely to be fruitful.

Since we have one known good state (same hardware running arch) and one known bad state (running 22.04, no other changes), we are at least close to knowing the variables.

On Mon, Apr 25, 2022 at 11:20 AM K.S. Bhaskar via plug <plug@lists.phillylinux.org> wrote:
No luck with fiddling with the power saving settings: it still randomly drops the network connection. This has to be one of the most puzzling issues I have encountered.

Thanks for the suggestions, all.

Regards
- Bhaskar

On Sat, Apr 23, 2022 at 6:09 AM K.S. Bhaskar <ksbhaskar@gmail.com> wrote:
Thanks, that's a good thought. I'll check it when I'm back in the office next week.

Regards
- Bhaskar

On Sat, Apr 23, 2022 at 5:29 AM Joe Rosato <rosatoj@gmail.com> wrote:
Looks like I'm late to the party but figured I throw a thought in... Could it be power saving settings? I read this pretty quickly but didn't see that mentioned...

Joe

On Fri, Apr 22, 2022, 9:45 PM K.S. Bhaskar via plug <plug@lists.phillylinux.org> wrote:
Here's how it played out.

dmesg was not helpful. It merely recorded that the NIC was down, and that some time later it was up. At least it told us that Linux knew the NIC was down.

I tried JP's ugly hack, having it run once a minute. No luck. When it went down, it stayed down until it decided to come up, for reasons known only to itself.

Debugging it by logging in at the console was no help, because the moment anyone logged in, moved a mouse or did something at the console, the network came back to life. It did not go down when I was logged in at the console (that's not to say that it would; just that it didn't on those occasions when I was logged in to see whether I could be logged in when it went down).

As I installed Kubuntu into a different partition from the prior Arch Linux, which was untouched by the Kubuntu installation, I reverted to Arch Linux and that's what it's running for the weekend. Since the Arch has not lost the network for several hours (vs. 20-30 minutes for Kubuntu), I'm confident that it's not a hardware problem.

All in all, it has been a very frustrating day.

Regards
– Bhaskar

On Fri, Apr 22, 2022 at 7:02 PM Rich Mingin (PLUG) via plug <plug@lists.phillylinux.org> wrote:
What nic? If it was a universal issue it would have been reported plenty by now. More likely a device specific bug.

On Fri, Apr 22, 2022 at 3:52 PM JP Vossen via plug <plug@lists.phillylinux.org> wrote:
On 4/22/22 15:25, K.S. Bhaskar via plug wrote:
> I did a fresh install of Kubuntu 22.04 this morning and a bizarre behavior has me scratching my head. As the machine (a 2017 PC, high end at the time) is used primarily as a server, and occasionally as a desktop, most of the time the monitor is powered down and the wireless mouse is turned off to conserve the battery. Every so often, it loses its network connection. ...
Really ugly hack?
```
*/5 * * * * root /bin/ping -c2 10.10.10.10 > /dev/null || { echo 'Resetting eth0!' ; /sbin/ifconfig eth0 down ; /sbin/ifconfig eth0 up ; ip route add default via 10.10.10.10 dev eth0 ; }

```

Where 10.10.10.10 is the node's default gateway, and "eth0" is the buggy interface. That's from when I had a box with a wonky USB Ethernet adapter. It didn't fix the problem, and it didn't always work, but...it worked sometimes.

Much better to find and fix the root cause, of course, but maybe this is a help until then, and might allow more data collection to find the problem.

Later,
JP
-- -------------------------------------------------------------------
JP Vossen, CISSP | http://www.jpsdomain.org/ | http://bashcookbook.com/
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___________________________________________________________________________
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General Discussion -- http://lists.phillylinux.org/mailman/listinfo/plug

___________________________________________________________________________
Philadelphia Linux Users Group -- http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion -- http://lists.phillylinux.org/mailman/listinfo/plug

___________________________________________________________________________
Philadelphia Linux Users Group -- http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion -- http://lists.phillylinux.org/mailman/listinfo/plug

___________________________________________________________________________
Philadelphia Linux Users Group -- http://www.phillylinux.org
Announcements - http://lists.phillylinux.org/mailman/listinfo/plug-announce
General Discussion -- http://lists.phillylinux.org/mailman/listinfo/plug