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initializing roscore, unkown host

asked 2012-07-30 03:02:49 -0500

Flowers gravatar image


OS: Fedora 14 ROS: Fuerte

Error, while initializing roscore:

Unable to contact my own server at [http://scitos:50689/]. This usually means that the network is not configured properly.

A common cause is that the machine cannot ping itself. Please check for errors by running:

ping scitos

For more tips, please see

ping scitos delivers

unkown host scitos

ping localhost works fine, ping likewise

Solutions according to ros-wiki is to set

ROS_HOSTNAME=localhost ROS_MASTER_URI=http://localhost:11311

this has not worked ping $ROS_HOSTNAME does fine, while ping $ROS_MASTER_URI returns

unknown host http://localhost:11311

Any ideas why this does not work? Maybe some issue concerning my network connection(using wireless for internet, still there are two ethernet accesses, which are currently not used)?

thx :-)

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2 Answers

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answered 2012-07-30 03:11:52 -0500

dornhege gravatar image

updated 2012-07-30 03:13:30 -0500

It's clear that you can't ping the ROS_MASTER_URI. Pinging the host in the ROS_MASTER_URI is the correct way.

Could you run a roscore after setting ROS_HOSTNAME?

The other way is checking your /etc/hosts. There should probably be a line like:   localhost

If you add   scitos

after that, you should be able to do ping scitos.

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answered 2012-07-30 03:19:08 -0500

Flowers gravatar image

updated 2012-07-30 03:20:50 -0500

Nope, it did not work, but I've found my mistake.

It seems that setting the value in .bashrc is not enough, you've got to write "export ROS_HOSTNAME=localhost" and then launching the roscore is no problem.


Thx a lot, that was the next thing I thought of.

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Putting the export... line in .bashrc should be sufficient. You'll need to source .bashrc, though. Once you open new terminals that should already be loaded. You can check with echo $ROS_HOSTNAME.

dornhege gravatar image dornhege  ( 2012-07-30 03:39:36 -0500 )edit

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Asked: 2012-07-30 03:02:49 -0500

Seen: 2,409 times

Last updated: Jul 30 '12