Re: [dtn-users] LTP Convergence Layer - Help needed!

[Nik Ansell <[e-mail]>]

Slight update...

A wireshark capture on node 2, showed the LTP segments being sent from node
1 to node 2 then being cancelled (LTP Segment 60 Cancel segment", but
nothing being sent from node 2 to node 3....

I then tested a 2-node LTPCL topology and this worked OK.

I suspect this problem is something to do with the LTPlib "Router"
functionality not being fully implemented in DTN2. However if someone could
confirm or shed any more light on the subject, this would be helpful,
thanks.


Kind Regards,
Nik

On Thu, Dec 3, 2015 at 9:22 PM, Nik Ansell <[e-mail]> wrote:

> Hi,
>
> I have successfully setup a 3 node UDPCL and TCPCL topology and am able to
> send bundles OK.
>
> Next I installed LTPLib and rebuilt DTN2, ensuring that ./configure found
> the location of LTPlib OK.
>
> I have updates the config files to use ltp, but for some reason no bundles
> seem to be sent or queued!
>
> If anyone could shed any light on a possible problem I will be forever in
> their debt, as bundles just seem to disappear!
>
> My testing so far has been starting dtnd on all 3 nodes, then running the
> dtnsend command twice to send 2 test bundles from node 1 to node 3.
> "dtnsend -s dtn://tx.dtn/a -d dtn://rx.dtn/g -t m -p "hello""
>
> I run dtnrecv on node 3:
> "dtnrecv dtn://rx.dtn/g -q -o F#####.bin"
>
> "bundle list" on nodes 1,2&3" returns zero bundles, so none are in the
> queue.
> "bundle stats" on node 1 returns:
>
> Bundle Statistics: 0 pending -- 0 custody -- -- bpq --  bpq -- 2 received
> -- 0 delivered -- 0 generated -- 2 transmitted -- 0 expired -- 0 duplicate
> -- 2 deleted -- 0 injected
>
> "link dump link_ltp1" on node 1 returns:
>
> Current link:
>
> Link link_ltp1:
>
> clayer: ltp
>
> type: ALWAYSON
>
> state: OPEN
>
> deleted: false
>
> nexthop: mx:4556
>
> remote eid: dtn:none
>
> mtu: 1400
>
> min_retry_interval: 5
>
> max_retry_interval: 600
>
> idle_close_time: 0
>
> potential_downtime: 30
>
> prevhop_hdr: false
>
> reincarnated: true
>
> used in fwdlog: true
>
> local_addr: 255.255.255.255 local_port: 4556
>
> remote_addr: 10.0.0.2 remote_port: 4556
>
> mtu: 1400
>
> Red/Green balance: all red
>
> ION mode: false
>
> Config files:
>
> Node1
> interface add udp0 udp
> interface add ltp0 ltp local_addr=$shorthostname
>
> # Create link to MX
> link add link_ltp1 mx:4556 ALWAYSON ltp mtu=1400 local_port=4556
> remote_port=4556 remote_addr=10.0.0.2
>
> # Add route to RX via MX
> route add dtn://rx.dtn/* link_ltp1
>
> Node2:
> interface add udp0 udp
> interface add ltp0 ltp local_addr=$shorthostname
>
> # Create link to TX
> link add link_ltp2 tx:4556 ALWAYSON ltp local_port=4556 remote_port=4556
> mtu=1400 remote_addr=10.0.0.1
>
> # Create link to RX
> link add link_ltp3 rx:4556 ALWAYSON ltp local_port=4556 remote_port=4556
> mtu=140 remote_addr=10.0.0.3
>
> # Add route to TX
> route add dtn://tx.dtn/* link_ltp2
>
> # Add route to RX
> route add dtn://rx.dtn/* link_ltp3
>
> Node3:
> interface add udp0 udp
> interface add ltp0 ltp local_addr=$shorthostname
>
> # Create link to MK
> link add link_ltp1 mx:4556 ALWAYSON ltp local_port=4556 remote_port=4556
> remote_addr=10.0.0.2
>
> # Add route to TX via MX
> route add dtn://tx.dtn/* link_ltp1
>
> Kind Regards,
> Nik
>