← Back to team overview

desktop-packages team mailing list archive

[Bug 1436330] Re: Network Manager doesn't set metric for local networks any more, causing connection issues

 

I tried silo-027 and it seems better (I think).

The packet loss problem remains though: thre's a ~20s break in traffic when the
new interface comes up or goes down though - for example:

laney@nightingale> ping -I wlan0 orangesquash.org.uk                                                                                                                                                ~
PING orangesquash.org.uk (85.119.82.37) from 192.168.1.135 wlan0: 56(84) bytes of data.
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=1 ttl=56 time=12.0 ms
[ … ]
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=20 ttl=56 time=10.6 ms
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=21 ttl=56 time=14.8 ms
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=22 ttl=56 time=13.9 ms
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=23 ttl=56 time=14.8 ms
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=24 ttl=56 time=13.3 ms
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=25 ttl=56 time=15.4 ms
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=26 ttl=56 time=14.3 ms
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=27 ttl=56 time=12.6 ms
*** there's a gap here ****
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=47 ttl=56 time=25.5 ms
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=48 ttl=56 time=17.3 ms
64 bytes from cripps.orangesquash.org.uk (85.119.82.37): icmp_seq=49 ttl=56 time=23.9 ms

with both interfaces up

laney@nightingale> ip ro
default via 192.168.1.1 dev enx0023563c3054  proto static  metric 100 
default via 192.168.1.1 dev wlan0  proto static  metric 400 
169.254.0.0/16 dev wlan0  scope link  metric 1000 
192.168.1.0/24 dev enx0023563c3054  proto kernel  scope link  metric 100 
192.168.1.0/24 dev wlan0  proto kernel  scope link  metric 400

-- 
You received this bug notification because you are a member of Desktop
Packages, which is subscribed to network-manager in Ubuntu.
https://bugs.launchpad.net/bugs/1436330

Title:
  Network Manager doesn't set metric for local networks any more,
  causing connection issues

Status in NetworkManager:
  Fix Released
Status in network-manager package in Ubuntu:
  In Progress
Status in network-manager source package in Vivid:
  Triaged

Bug description:
  [Impact]
  NM changed its method of setting routes on systems, and no longer attaches a metric value specific to the type of device being used. These values were used to prioritize connections, so that for example, when connected to both wired and wireless at the same time, wired can be used in priority over wireless without incurring packet loss.
  Currently, when connected to both wired and wireless are connected to the same subnet, the user may notice connectivity issues since packets are sent in a round-robin fashion over all default routes on the same subnet with the same metric.

  [Test Case]
  1- Connect to a wireless network.
  2- Connect to the same network over Ethernet both connections should come up on the same subnet.
  3- Make sure there is no packet loss, and that there are specific metric values for each default route, as displayed by 'ip route'.

  [Regression Potential]
  Since handling default routes properly involves correcting the behavior for all device types, VPN behavior may change to pick up the default routes in all cases, over a wired connection. It's also possible that a connection pick up the default route when it is not meant to.

  ---

  With Vivid, having two connections to the same network subnet is
  unstable due to missing metrics for local networks.

  Example:

  Being connected to 192.168.1.0/24 via both wired and wireless will
  cause connectivity issues as sent packets hop between the two
  interfaces.

  It used to be that this wasn't an issue. I would go between work and
  home and plug in and my machine would automatically connect to
  wireless and it would use the lower metric ethernet interface for all
  communications, while the wlan interface would remain connected but
  unused.

  ProblemType: Bug
  DistroRelease: Ubuntu 15.04
  Package: network-manager 0.9.10.0-4ubuntu11
  ProcVersionSignature: Ubuntu 3.19.0-9.9-generic 3.19.1
  Uname: Linux 3.19.0-9-generic x86_64
  NonfreeKernelModules: nvidia
  ApportVersion: 2.16.2-0ubuntu4
  Architecture: amd64
  CurrentDesktop: KDE
  Date: Wed Mar 25 09:17:27 2015
  IfupdownConfig:
   # interfaces(5) file used by ifup(8) and ifdown(8)
   auto lo
   iface lo inet loopback
  InstallationDate: Installed on 2015-01-25 (58 days ago)
  InstallationMedia: Kubuntu 14.10 "Utopic Unicorn" - Release amd64 (20141022.1)
  SourcePackage: network-manager
  UpgradeStatus: Upgraded to vivid on 2015-03-17 (8 days ago)
  nmcli-nm: Error: command ['nmcli', '-f', 'all', 'nm'] failed with exit code 2: Error: Object 'nm' is unknown, try 'nmcli help'.

To manage notifications about this bug go to:
https://bugs.launchpad.net/network-manager/+bug/1436330/+subscriptions


References