libcore.io.ErrnoException: sendto failed: ENETUNREACH (Network is unreachable)

[geeksville]

java.net.SocketException: sendto failed: ENETUNREACH (Network is unreachable)
at libcore.io.IoBridge.maybeThrowAfterSendto(IoBridge.java:499)
at libcore.io.IoBridge.sendto(IoBridge.java:468)
at java.net.PlainDatagramSocketImpl.send(PlainDatagramSocketImpl.java:182)
at java.net.DatagramSocket.send(DatagramSocket.java:281)
at com.geeksville.mavlink.MavlinkUDP.doSendMavlink(MavlinkUDP.scala:50)
at com.geeksville.mavlink.MavlinkSender$$anonfun$onReceive$1.applyOrElse(MavlinkSender.scala:41)
at akka.actor.Actor$class.aroundReceive(Actor.scala:465)
at com.geeksville.mavlink.MavlinkUDP.aroundReceive(MavlinkUDP.scala:24)
at akka.actor.ActorCell.receiveMessage(ActorCell.scala:516)
at akka.actor.ActorCell.invoke(ActorCell.scala:487)
at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:241)
at akka.dispatch.Mailbox.run(Mailbox.scala:223)
at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:393)
at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
Caused by: libcore.io.ErrnoException: sendto failed: ENETUNREACH (Network is unreachable)
at libcore.io.Posix.sendtoBytes(Native Method)
at libcore.io.Posix.sendto(Posix.java:156)
at libcore.io.BlockGuardOs.sendto(BlockGuardOs.java:177)
at libcore.io.IoBridge.sendto(IoBridge.java:466)
... 15 more
java.net.SocketException: sendto failed: ENETUNREACH (Network is unreachable)
at libcore.io.IoBridge.maybeThrowAfterSendto(IoBridge.java:499)
at libcore.io.IoBridge.sendto(IoBridge.java:468)
at java.net.PlainDatagramSocketImpl.send(PlainDatagramSocketImpl.java:182)
at java.net.DatagramSocket.send(DatagramSocket.java:281)
at com.geeksville.mavlink.MavlinkUDP.doSendMavlink(MavlinkUDP.scala:50)
at com.geeksville.mavlink.MavlinkSender$$anonfun$onReceive$1.applyOrElse(MavlinkSender.scala:41)
at akka.actor.Actor$class.aroundReceive(Actor.scala:465)
at com.geeksville.mavlink.MavlinkUDP.aroundReceive(MavlinkUDP.scala:24)
at akka.actor.ActorCell.receiveMessage(ActorCell.scala:516)
at akka.actor.ActorCell.invoke(ActorCell.scala:487)
at akka.dispatch.Mailbox.processMailbox(Mailbox.scala:241)
at akka.dispatch.Mailbox.run(Mailbox.scala:223)
at akka.dispatch.ForkJoinExecutorConfigurator$AkkaForkJoinTask.exec(AbstractDispatcher.scala:393)
at scala.concurrent.forkjoin.ForkJoinTask.doExec(ForkJoinTask.java:260)
at scala.concurrent.forkjoin.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:1339)
at scala.concurrent.forkjoin.ForkJoinPool.runWorker(ForkJoinPool.java:1979)
at scala.concurrent.forkjoin.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:107)
Caused by: libcore.io.ErrnoException: sendto failed: ENETUNREACH (Network is unreachable)
at libcore.io.Posix.sendtoBytes(Native Method)
at libcore.io.Posix.sendto(Posix.java:156)
at libcore.io.BlockGuardOs.sendto(BlockGuardOs.java:177)
at libcore.io.IoBridge.sendto(IoBridge.java:466)
... 15 more