** Changed in: network-manager (Fedora)
       Status: Unknown => Fix Released

** Changed in: network-manager (Fedora)
   Importance: Unknown => Medium

-- 
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/993571

Title:
  Wifi disconnect/reconnects fairly often (from multiple times an hour
  to multiple times per day) because of ip-config-unavailable

Status in network-manager package in Ubuntu:
  Fix Released
Status in network-manager source package in Precise:
  Fix Released
Status in network-manager package in Fedora:
  Fix Released

Bug description:
  [Impact]
  Affects IPv6 users on dual-stack or single-ipv6-stack networks; causes 
frequent disconnects if a sufficient number of packets are missed (especially 
towards the end of the RDNSS/DNSSL entry lifetime). Patch is pretty 
self-contained and only affects IPv6, only in the case of SLAAC (stateless 
autoconfiguration) since DHCPv6-based networks provide DNS information in a 
different manner.

  [Development Fix]
  Package network-manager 0.9.4.0-0ubuntu5 which fixes all of the same bugs 
targetted to be fixed with this SRU; including bug 993379 and bug 988183. Also 
tested in a PPA (ppa:mathieu-tl/nm) prior to upload to quantal and 
precise-proposed.

  [Stable Fix]
  The small patch based on the patch provided for testing in the linked RedHat 
bug; which is the exact same (no changes required) patch as revised from the 
original (from the redhat bug and attached to this bug report) as was uploaded 
to Quantal after testing in a PPA. Adds a method for renewing/refreshing RDNSS 
and DNSSL data from Router Advertisements. At lifetime/2 a first router 
solicitation will be sent to try and force an update; if no response is 
received the same process (timeout/2) is applied again to send another 
solicitation message to routers asking for a RA, until one is received and 
refreshes RDNSS/DNSSL data or until data expiry.

  [Test case]
  Requires a working IPv6 setup: see below.
  1) Connect to an IPv6 network that provides RDNSS data. (DNSSL uses the same 
procedure but is not available in current Precise kernels)
  2) Observe whether the connection is stable.

  [Regression Potential]
  Only affects IPv6 SLAAC, which means IPv6 could be disabled to mitigate any 
issues encountered. Users could be affected by a (minimal) increase in the 
number of packets sent over the network due to the sending of Router 
Solicitation messages. On high-latency links this may cause issues. New RS 
messages may cause RAs giving new IPv6 addresses more quickly than anticipated.

  ---

  Testing IPV6 RDNSS with radvd:
  You can use a configuration similar to the following, on a router where the 
vlan2 interface would be the outside interface:

  interface br0 { 
   MinRtrAdvInterval 3; 
   MaxRtrAdvInterval 10; 
   AdvLinkMTU 1280; 
   AdvSendAdvert on; 
   prefix 0:0:0:1::/64 { 
   AdvOnLink on; 
   AdvAutonomous on; 
   AdvValidLifetime 86400; 
   AdvPreferredLifetime 86400; 
   Base6to4Interface vlan2; 
   }; 
   RDNSS 2001:503:ba3e::2:30 2001:500:2d::d {};
   }; 

  This particular setup uses 6to4 to provide IPv6 connectivity; and
  announces a.root-servers.net and d.root-servers.net as DNS nameservers
  to use.

  In control of the router one could kill the radvd daemon to simulate
  lost packets and observe attempts to refresh RDNSS data, and bring the
  daemon back up again to see how with a RA the RDNSS information gets
  refreshed.

  Packet captures are also useful to observe the behavior.

  ---
  Original bug report description:

  To start with, let me confirm that I do NOT have any message in my
  kernel log complaining about the kernel not being able to set the
  default IPv6 route, so that's a different bug from the what you're
  probably thinking about ;)

  This one happens every few minutes or every few hours, as far as I can
  tell, only on wireless networks (for a yet unknown reason) and only on
  dual-stack networks.

  I reproduced it on a variety of equipment  (3 laptops, 2 with 2 different 
intel wireless chips, one with atheros) and on 4 different brands of access 
points. Only thing in common, the network configuration is almost identical.
  That's a standard dual-stack setup with IPv4 provided over DHCP and IPv6 
through radvd (SLAAC) with RDNSS set.

  I'm attaching a debug log. Look for "ip-config-unavailable" to spot
  the few occurrences of the bug in it.

  This most likely is the same bug as described in:
  https://bugzilla.redhat.com/show_bug.cgi?id=753482

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/network-manager/+bug/993571/+subscriptions

-- 
Mailing list: https://launchpad.net/~desktop-packages
Post to     : desktop-packages@lists.launchpad.net
Unsubscribe : https://launchpad.net/~desktop-packages
More help   : https://help.launchpad.net/ListHelp

Reply via email to