#7942 NORM 9.1.0: No information received for new buddy

[Zarro Boogs per Child]

#7942: No information received for new buddy
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   Reporter:  epmfairweather  |       Owner:  ypod         
       Type:  enhancement     |      Status:  new          
   Priority:  normal          |   Milestone:  9.1.0        
  Component:  cerebro         |     Version:  not specified
 Resolution:                  |    Keywords:               
Next_action:  never set       |    Verified:  0            
  Blockedby:                  |    Blocking:               
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Changes (by ypod):

  * type:  defect => enhancement


Comment:

 I have been concerned with this issue for some time now, but I would not
 characterize this as a bug, but rather a missing feature.

 This issue occurs when some node is reported as present somewhere in the
 network (through some witness), but there is no usable connection between
 that and the current node so that the current node can receive the remote
 node's profile. This happens when:
 a) a regular interface is used (anything other than msh0) and the two
 nodes are not in range with each other, but are aware of the presence of
 each other through some other node that acts as the witness.
 b) a mesh interface is used, but the end-to-end link quality between the
 nodes is too poor to transfer any data.
 c) there is some highly irregular and asymmetric link between the two
 nodes that causes all frames in one direction to be lost. This has been
 observed very few times in the past: in one case the interface was
 actually able to receive frames from a different channel and the other was
 probably some erratic driver/firmware behavior.

 You are probably in the first case (you used wlan0?).

 I can think of two ways to mitigate this behavior:

 1) allow profiles to proactively propagate throughout the network. Always
 ask a witness to provide the profile of its own direct neighbors (that are
 not direct neighbors to the node itself; the node already has this
 information). Inductively, this will cause profiles to percolate
 throughout the mesh network.
 2) modify cerebro to only request profiles from direct neighbors

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Ticket URL: <http://dev.laptop.org/ticket/7942#comment:1>
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