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rocon: 'already connected to this hub'

asked 2014-08-25 22:36:43 -0600

bjem85 gravatar image


I am following through the roscon installation tutorial for ROS Hydro, but I am getting stuck at the verification step.

The instructions say to execute:

> . /opt/ros/hydro/setup.bash
> rocon_launch chatter_concert chatter.concert

When I do this the terminal windows spawn as expected. However they all have a warning:

[WARN] [WallTime: 1409023936.036277] Gateway : not registering on the hub [already connected to this hub]
[WARN] [WallTime: 1409023936.544642] Gateway : not registering on the hub [already connected to this hub]

Is this warning a problem or not? The hub seems to be running as though it's a daemon, as closing the terminal down and starting this command again does not make the warning go away.

I would post a screen shot but I don't have enough points (need at least 20) to do so.

Kind Regards Bart

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I don't know about this message in particular, but warnings generally imply that a given operation worked, although something was noticed in passing.

joq gravatar image joq  ( 2014-08-27 14:42:22 -0600 )edit

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answered 2014-09-10 21:58:24 -0600

Daniel Stonier gravatar image

Ok, digging back through my memory, I believe this is because it was starting a gateway with default settings to look for a hub on localhost, and also via zeroconf. If the localhost hub was found (which it did for chatter_concert), then zeroconf discovery would throw this warning when it would discover the same hub.

This has been updated on the hydro-devel/indigo branches so that it doesn't do this double lookup.

In short, don't worry about it :)

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I haven't verified this but it sounds reasonable.

bjem85 gravatar image bjem85  ( 2014-09-16 03:51:58 -0600 )edit

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Asked: 2014-08-25 22:36:43 -0600

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Last updated: Sep 10 '14