On Fri, Mar 30, 2012 at 2:18 PM, dan firstname.lastname@example.org wrote:
ok, this is an option I had considered, but I'm worried that link alternation wont be an option as the radios only have a single radio and the alternate path is through a completely different radio/device connected via ethernet.
batman-adv makes no difference between ethernet or radio interfaces, they are all simply just interfaces that somehow link to other batman-adv nodes (with some -or zero- packet loss) so link alternation would work the same: if packet comes in through radio, and batman-adv can reach the destination through the ethernet port (it doesn't matter if that implies hopping through more batman-adv nodes) it will prefer sending it through this "alternate" path (alternate in the sense it doesn't use the same interface the packet came in)
As far as vlans are concerned, are you saying to have a vlan on the router for each attached picostation and then set the picostations ethernet interface to match that vlan? Then I can add all the vlans to bat0?
maybe if you could clarify this for me. for link alternating, do the two nodes need to be one hop neighbors?
Nope, not needed. And in fact it is "interface alternation" (subtle difference). if packet comes in through interface A, and the final destination is reachable through 2 different paths that start at interface A and interface B respectively, it will send the packet through interface B to avoid reusing interface A. It doesn't matter if between interface B and final destination there are N hops.
A long thread earlier this month was particularly clarifying on the subject. https://lists.open-mesh.org/pipermail/b.a.t.m.a.n/2012-March/006351.html
according to docs, link alternating works in this scenario, where both links are good: node1_Link1------------node2_Link1 node1_Link2------------node2_Link2
but what about this: node1_Link1------node3_Link1------node2_Link1 node1_Link2------node4_Link2------node2_Link2
will node1 and node2 still have link alternation?
Yes. in addition you might also be interested in interface bonding, which is not enabled by default but can be activated after understanding a few caveats. it's documented on batctl manpage online.
This is basically what the central router + picostations with the picostations running batman-adv would look like
so supernode2 is then a 3 hop neighbor to supernode1. So will link alternation work here? Lets just say that supernode1 has the backhaul and supernode2 has nothing except it's link to supernode1. Ideally, SN2 gets the faster, dual link connection to SN1.
If picostations are only connected point-to-point to each other, and there are no other clients sending traffic to them (except the supernodes), then interface alternating won't take advantage of the "faster dual link connection" You must use interface bonding to achieve that.
Interface alternating would be useful, for example, if picostation2 from supernode2 was receiving a radio transmission from a distant supernode3 (not pictured) destined at supernode1. Then, instead of trying to relay the packets through that same picostation2, it would use picostation1 to send them and avoid reusing the same interface.