[Pkg-utopia-maintainers] Bug#818596: network-manager: randomly drops ethernet connection, about 1 time / day

[Julian Gilbey]

Package: network-manager
Version: 1.1.91-1
Severity: important

I have a bizarre problem.  For about the last month, network-manager
(or something else perhaps) has been dropping my ethernet connection
from my server (which is normally on full-time).

netstat -rn currently shows:

Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
0.0.0.0         192.168.0.1     0.0.0.0         UG        0 0          0 eth0
192.168.0.0     0.0.0.0         255.255.255.0   U         0 0          0 eth0

but then at random times, it drops the eth0 interface completely,
leaving

Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface

and no network connectivity.

Checking my aptitude logs, this seems to have started around the time
I upgraded from network-manager 1.0.10-2+b1 (and network-manager-gnome
1.0.10-1) to 1.1.90-3, and is still occurring with the current
version.

I don't see anything obvious in the system logs suggesting that a
connection has been dropped.

I am happy to help with debugging this, but don't know how to start.
I could set the logging level to DEBUG if you think this would be of
use?

Thanks,

   Julian

-- System Information:
Debian Release: stretch/sid
  APT prefers testing
  APT policy: (500, 'testing'), (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.3.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_GB.utf8, LC_CTYPE=en_GB.utf8 (charmap=UTF-8) (ignored: LC_ALL set to en_GB.UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages network-manager depends on:
ii  adduser                3.113+nmu3
ii  dbus                   1.10.6-1
ii  init-system-helpers    1.29
ii  isc-dhcp-client        4.3.3-8
ii  libbluetooth3          5.36-1
ii  libc6                  2.21-9
ii  libglib2.0-0           2.46.2-3
ii  libgnutls30            3.4.9-2
ii  libgudev-1.0-0         230-3
ii  libmm-glib0            1.4.12-1
ii  libndp0                1.4-2
ii  libnewt0.52            0.52.18-3
ii  libnl-3-200            3.2.27-1
ii  libnm0                 1.1.91-1
ii  libpam-systemd         229-2
ii  libpolkit-agent-1-0    0.105-14.1
ii  libpolkit-gobject-1-0  0.105-14.1
ii  libreadline6           6.3-8+b4
ii  libsoup2.4-1           2.52.2-1
ii  libsystemd0            229-2
ii  libteamdctl0           1.23-1
ii  libuuid1               2.27.1-4
ii  lsb-base               9.20160110
ii  policykit-1            0.105-14.1
ii  udev                   229-2
ii  wpasupplicant          2.3-2.3

Versions of packages network-manager recommends:
ii  crda            3.13-1+b1
ii  dnsmasq-base    2.75-1
ii  iptables        1.6.0-2
ii  iputils-arping  3:20150815-2
ii  modemmanager    1.4.12-1
pn  ppp             <none>

Versions of packages network-manager suggests:
pn  libteam-utils  <none>

-- Configuration Files:
/etc/NetworkManager/NetworkManager.conf changed:
[main]
plugins=ifupdown,keyfile
no-auto-default=xx:xx:xx:xx:xx:xx,  <-- this is my ethernet card MAC address
[ifupdown]
managed=false


-- no debconf information