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ros2 node list empty

When trying to echo what certain topics are publishing I was executing ros2 topic echo <name-of-the-topic> and it wasn't able to echo nothing at all. I used rqt-graph to see if the topics and nodes appeared there and they do, so I used both commands ros2 topic list and ros2 node list to see if they appeared there, and they don't.

To be accurate, when using ros2 node list the list appears empty and when using ros2 topic list 2 values appear: \parameter_events and \rosout.

Asked by pablo.arandarod on 2022-01-18 07:28:30 UTC

Comments

You'll need to provide more detail here. Is this a multi-machine setup? Is there some node you're running that should be providing data?

Asked by cst0 on 2022-01-18 12:35:17 UTC

If ros2 topic list is showing only \parameter_events and rosout only, then I am afraid there are no nodes running

Asked by aarsh_t on 2022-01-18 13:03:08 UTC

@cst0 It is all in the same machine, I'm just running a simulation in Gazebo where I'm spawning a robot and gazebo publish some info of various sensors.

Regarding @aarsh_t, when I use rqt-graph nodes and topics related to the simulation do appear.

Asked by pablo.arandarod on 2022-01-18 15:20:29 UTC

Can you upload the screenshot of both in parallel?

Asked by aarsh_t on 2022-01-19 01:26:03 UTC

Can you pls show the output of ros2 topic info <name-of-the-topic> and ros2 topic info <name-of-the-topic> -v

Asked by osilva on 2022-01-19 14:12:07 UTC

Also added you points so you can display the rqt-graph requested by @aarsh_t.

Asked by osilva on 2022-01-19 14:14:36 UTC

@osilva @aarsh_t basically I decided to delete my current installation (actually, not that much of an installation, but a build) and decided to install through apt and it is working fine for now

Asked by pablo.arandarod on 2022-01-20 08:13:06 UTC

Thank you @pablo.arandarod for the update.

Asked by osilva on 2022-01-20 08:17:57 UTC

Answers