Network restart after suspend is unreliable

[Oliver Klee]

After suspending my computer to standby and then waking it up again, networking restarts unreliably: Sometimes it restarts fine, sometimes it takes a few seconds to restart, and sometimes it takes more than a minute (I didn't wait longer).

When the network wakeup is not finished, pings to my local router get a timeout, and "sudo service networking restart" creates this output:

klee@gonzales:~$ ping router
PING router (192.168.100.254) 56(84) bytes of data.
From gonzales (192.168.100.2) icmp_seq=1 Destination Host Unreachable
^C
--- router ping statistics ---
1 packets transmitted, 0 received, +1 errors, 100% packet loss, time 0ms

klee@gonzales:~$ sudo service networking status
● networking.service - Raise network interfaces
   Loaded: loaded (/lib/systemd/system/networking.service; enabled; vendor preset: enabled)
   Active: active (exited) since Mon 2019-04-29 11:16:05 CEST; 12h ago
     Docs: man:interfaces(5)
 Main PID: 1239 (code=exited, status=0/SUCCESS)
    Tasks: 0 (limit: 4915)
   Memory: 0B
   CGroup: /system.slice/networking.service

Apr 29 11:15:58 gonzales systemd[1]: Starting Raise network interfaces...
Apr 29 11:15:59 gonzales ifup[1239]: ifup: waiting for lock on /run/network/ifstate.eno1
Apr 29 11:16:05 gonzales systemd[1]: Started Raise network interfaces.

After I have done a "sudo service networking restart", the output is this:

klee@gonzales:~$ sudo service networking status
● networking.service - Raise network interfaces
   Loaded: loaded (/lib/systemd/system/networking.service; enabled; vendor preset: enabled)
   Active: active (exited) since Mon 2019-04-29 23:17:00 CEST; 5s ago
     Docs: man:interfaces(5)
  Process: 3701 ExecStart=/sbin/ifup -a --read-environment (code=exited, status=0/SUCCESS)
 Main PID: 3701 (code=exited, status=0/SUCCESS)
    Tasks: 1 (limit: 4915)
   Memory: 7.4M
   CGroup: /system.slice/networking.service
           └─3728 /sbin/dhclient -1 -4 -v -pf /run/dhclient.eno1.pid -lf /var/lib/dhcp/dhclient.eno1.leases -I -df /var/lib/dhcp/dhclient6.eno1.leases eno1

Apr 29 23:16:59 gonzales ifup[3701]: DHCPDISCOVER on eno1 to 255.255.255.255 port 67 interval 5 (xid=0x53439c24)
Apr 29 23:16:59 gonzales dhclient[3728]: DHCPOFFER of 192.168.100.2 from 192.168.100.254
Apr 29 23:16:59 gonzales dhclient[3728]: DHCPREQUEST for 192.168.100.2 on eno1 to 255.255.255.255 port 67 (xid=0x249c4353)
Apr 29 23:16:59 gonzales ifup[3701]: DHCPOFFER of 192.168.100.2 from 192.168.100.254
Apr 29 23:16:59 gonzales ifup[3701]: DHCPREQUEST for 192.168.100.2 on eno1 to 255.255.255.255 port 67 (xid=0x249c4353)
Apr 29 23:16:59 gonzales dhclient[3728]: DHCPACK of 192.168.100.2 from 192.168.100.254 (xid=0x53439c24)
Apr 29 23:16:59 gonzales ifup[3701]: DHCPACK of 192.168.100.2 from 192.168.100.254 (xid=0x53439c24)
Apr 29 23:17:00 gonzales dhclient[3728]: bound to 192.168.100.2 -- renewal in 42225 seconds.
Apr 29 23:17:00 gonzales ifup[3701]: bound to 192.168.100.2 -- renewal in 42225 seconds.
Apr 29 23:17:00 gonzales systemd[1]: Started Raise network interfaces.

(And the pings work fine again, too.)

This is a regression after the upgrade from 18.10 (where networking wakeup worked fine) to 19.04.

Version info:

klee@gonzales:~$ lsb_release -rd
Description: Ubuntu 19.04
Release: 19.04

netbase 5.6
ifupdown 0.8.34ubuntu2

ProblemType: Bug
DistroRelease: Ubuntu 19.04
Package: netbase 5.6
ProcVersionSignature: Ubuntu 5.0.0-13.14-generic 5.0.6
Uname: Linux 5.0.0-13-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.10-0ubuntu27
Architecture: amd64
CurrentDesktop: KDE
Date: Mon Apr 29 23:19:00 2019
Dependencies:

InstallationDate: Installed on 2016-08-06 (996 days ago)
InstallationMedia: Kubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
PackageArchitecture: all
SourcePackage: netbase
UpgradeStatus: Upgraded to disco on 2019-04-21 (8 days ago)

[Oliver Klee (launchpad-oliverklee)]

This problem has not occurred on my machine for some time now. So I think this bug can be closed.