Werid Multiple Machines Problem -

Question

Hi,

I'm not sure of this is simply a compatibility issue or something else. On one machine I have fuerte an the other electric. Both the simple talker and listener tut's work fine with run on each machine.

I've set export ROS_MASTER_URI=http://192.168.1.40:11311 to the machine with has roscore running on.

Running roscore and talker on machine A then the listener on machine B - nothing happens. However "rosnode list" on machine A recognises lists the listener (and the listing updates when I kill the listener).

Similarly if I set up two listeners the older one gets killed off if that was running on machine B - but not the other way around.

So there seems to be some kind of comms going one. But not the whole thing.

Looking at http://www.ros.org/wiki/ROS/Tutorials/MultipleMachines hasn't reveiled anything. Pinging etc all seems okay.

Any ideas anyone?

Thanks in advance

Mark

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Originally posted by MarkyMark2012 on ROS Answers with karma: 1834 on 2012-07-06

Post score: 1

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Original comments

Comment by Eric Perko on 2012-07-06:
Could you update your question to include the ROS_MASTER_URI you are setting on each machine and the ROS_IP/ROS_HOSTNAME you are setting on each?

Answer 1

While running nodes from two different ROS distributions in the same graph may sometime work, it is definitely not supported.

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Originally posted by joq with karma: 25443 on 2012-07-06

This answer was NOT ACCEPTED on the original site

Post score: 1

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Original comments

Comment by Thomas on 2012-07-07:
Exactly. This is just something you should not attempt. And maybe roscomm should issue a warning when one tries to do so.

Answer 2

Okay found the issue. Came down to DNS problem (Machine B is a VM and the VM network bridge was assigning it an unusual address). Updated the /etc/hosts file with the machine name where roscore is running and working as expected.

Thanks for your input all

M

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Originally posted by MarkyMark2012 with karma: 1834 on 2012-07-07

This answer was ACCEPTED on the original site

Post score: 2