Gazebo hangs at "Requesting list of world names. The server may be busy downloading resources. Please be patient." about gz-sim

[osrf-migration]

Original comment by Til Hoff (Bitbucket: turakar).

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I thin the problem is something with ign-transport, because

• ign-transport's tests fail on my machine
• the same error occurs if I only start the client using ign gazebo -g

Filed an issue (gazebosim/gz-transport#113) for this.

[osrf-migration]

Original comment by Paul Jurczak (Bitbucket: pauljurczak).

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I have the same issue executing ign gazebo -g -v4 on Ubuntu 18.04.3 with Ignition Gazebo GUI v2.11.0. I installed by following instructions from https://bitbucket.org/osrf/subt/wiki/tutorials/SystemSetupInstall.

[osrf-migration]

Original comment by Alexander Moriarty (Bitbucket: Alexander Moriarty).

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I have the same issue, with Ubuntu 18.04.3 and Ignition Gazebo 2.12.0
I did a fresh install, and was just following through with the documentation.
I first ran without the -v 4 and it did not response until I sent sigkill. In the meantime, the GUI is just a blank black window.

Running with

ign gazebo shapes.sdf -v 4

The output prints same log line above, repeatedly for several minutes… It repeated the log line for the time taken to drink one beer.

[GUI] [Dbg] [ign.cc:230] GUI requesting list of world names. The server may be busy downloading resources. Please be patient.

https://github.com/ignitionrobotics/ign-gazebo/blob/91c840f94a10c6711635ee0c55a650e164604371/src/cmd/ign.cc#L224

  // This loop is here to allow the server time to download resources.
  // \todo(nkoenig) Async resource download. Search for "Async resource
  // download in `src/Server.cc` for corresponding todo item. This todo is
  // resolved when this while loop can be removed.
  while (!sigKilled && !executed)
  {
    igndbg << "Requesting list of world names. The server may be busy "
      << "downloading resources. Please be patient." << std::endl;
    executed = node.Request(service, timeout, worldsMsg, result);
  }

I haven’t looked into the code further to see why node.Request(service, timeout, worldMsg, result); isn’t doing any logging when it hits the timeout but I think this while should probably have some sort of exit condition.

[osrf-migration]

Original comment by Louise Poubel (Bitbucket: chapulina, GitHub: chapulina).

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Til Hoff (turakar) , I see you have a workaround for Fedora on the ign-transport issue, i.e. IGN_IP=127.0.0.1. Does that fix this issue as well?

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Paul Jurczak (pauljurczak) and Alexander Moriarty (Alexander Moriarty) , could you try these debugging steps:

1. Start only the server: ign gazebo -v 4 -s
2. List all services: ign service -l
   • you should see /gazebo/worlds
3. Call the world name service: ign service -s /gazebo/worlds --reqtype ignition.msgs.Empty --reptype ignition.msgs.StringMsg_V --timeout 1000 --req 'unused:false'
   • you should get data: "default"

Let me know if any of the above fails.

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the same error occurs if I only start the client using ign gazebo -g

That's expected. The client waits in a loop until a server is available. This is meant to support the user starting the client and server separately in any order. Perhaps the warning could be clearer about this.

I think this while should probably have some sort of exit condition.

It has 2: either the service succeeds or the user sigkills the process. At the moment, there's nothing you can do with the client if the server is not available, so there's no point in proceeding without getting a response from the server. I suppose we could let the user specify a maximum number of tries before shutting down, if that would help.

[osrf-migration]

Original comment by Alexander Moriarty (Bitbucket: Alexander Moriarty).

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I ran ign gazabo -v 4 -s then ign service -l and I see no services listed.

ign gazebo -v 4 -s
[Msg] Ignition Gazebo Server v2.12.0
[Msg] Loading default world.
[Dbg] [EntityComponentManager.cc:627] Using components of type [2251689575469537287] / [ign_gazebo_components.World].
[Dbg] [EntityComponentManager.cc:627] Using components of type [13994732549916512682] / [ign_gazebo_components.Name].
[Dbg] [EntityComponentManager.cc:627] Using components of type [12592746352568925681] / [ign_gazebo_components.Gravity].
[Dbg] [EntityComponentManager.cc:627] Using components of type [13224937992534617849] / [ign_gazebo_components.MagneticField].
[Dbg] [EntityComponentManager.cc:627] Using components of type [8753193699724811771] / [ign_gazebo_components.Wind].
[Dbg] [EntityComponentManager.cc:627] Using components of type [12173050716021724529] / [ign_gazebo_components.WorldLinearVelocity].
[Dbg] [EntityComponentManager.cc:627] Using components of type [15943768124495574352] / [ign_gazebo_components.WorldLinearVelocitySeed].
[Dbg] [EntityComponentManager.cc:627] Using components of type [3297509811873971798] / [ign_gazebo_components.ParentEntity].
[Dbg] [EntityComponentManager.cc:627] Using components of type [17100615127981600159] / [ign_gazebo_components.Scene].
[Dbg] [EntityComponentManager.cc:627] Using components of type [8064491505919932473] / [ign_gazebo_components.Level].
[Dbg] [EntityComponentManager.cc:627] Using components of type [2668898242563798256] / [ign_gazebo_components.DefaultLevel].
[Dbg] [EntityComponentManager.cc:627] Using components of type [11371360182141354106] / [ign_gazebo_components.LevelEntityNames].
[Dbg] [SimulationRunner.cc:745] Loaded system [ignition::gazebo::systems::SceneBroadcaster] for entity [1]
[Dbg] [SimulationRunner.cc:745] Loaded system [ignition::gazebo::systems::Physics] for entity [1]
[Msg] Create service on [/world/default/create]
[Msg] Remove service on [/world/default/remove]
[Msg] Pose service on [/world/default/set_pose]
[Dbg] [SimulationRunner.cc:745] Loaded system [ignition::gazebo::systems::UserCommands] for entity [1]
[Msg] Loaded level [3]
[Msg] Serving world controls on [/world/default/control] and [/world/default/playback/control]
[Msg] Serving GUI information on [/world/default/gui/info]
[Msg] World [default] initialized with [default_physics] physics profile.
[Msg] Found no publishers on /stats, adding root stats topic
[Msg] Found no publishers on /clock, adding root clock topic
[Dbg] [SimulationRunner.cc:394] Creating PostUpdate worker threads: 2
[Dbg] [SimulationRunner.cc:407] Creating postupdate worker thread (0)
[Msg] Serving scene information on [/world/default/scene/info]
[Msg] Serving graph information on [/world/default/scene/graph]
[Msg] Serving full state on [/world/default/state]
[Msg] Publishing scene information on [/world/default/scene/info]
[Msg] Publishing entity deletions on [/world/default/scene/deletion]
[Msg] Publishing state changes on [/world/default/state]
[Msg] Publishing pose messages on [/world/default/pose/info]
[Msg] Publishing dynamic pose messages on [/world/default/dynamic_pose/info]

ign gazebo -v 4 -g
[Msg] Ignition Gazebo GUI    v2.12.0
[Dbg] [Application.cc:87] Initializing application.
[GUI] [Dbg] [Application.cc:407] Create main window
[GUI] [Dbg] [ign.cc:230] GUI requesting list of world names. The server may be busy downloading resources. Please be patient.
[GUI] [Dbg] [ign.cc:230] GUI requesting list of world names. The server may be busy downloading resources. Please be patient.
[GUI] [Dbg] [ign.cc:230] GUI requesting list of world names. The server may be busy downloading resources. Please be patient.
[GUI] [Dbg] [ign.cc:230] GUI requesting list of world names. The server may be busy downloading resources. Please be patient.

‌

[osrf-migration]

Original comment by Alexander Moriarty (Bitbucket: Alexander Moriarty).

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I’ve just checked and I have two versions of libignition-transport installed this may be causing the error. I’ll try again next week. One libignition-transport4 is installed as a dependency of gazebo9 and libignition-transport7 as a dependency of ignition-gazebo2

apt search libignition-transport | grep installed

WARNING: apt does not have a stable CLI interface. Use with caution in scripts.

libignition-transport4/bionic,now 4.0.0+dfsg-4 amd64 [installed,automatic]
libignition-transport4-dev/bionic,now 4.0.0+dfsg-4 amd64 [installed,automatic]
libignition-transport7/unknown,now 7.1.0-1~bionic amd64 [installed,automatic]
libignition-transport7-core-dev/unknown,now 7.1.0-1~bionic amd64 [installed,automatic]
libignition-transport7-dev/unknown,now 7.1.0-1~bionic amd64 [installed,automatic]
libignition-transport7-log/unknown,now 7.1.0-1~bionic amd64 [installed,automatic]
libignition-transport7-log-dev/unknown,now 7.1.0-1~bionic amd64 [installed,automatic]

Update: uninstalling the earlier version did not fix anything.

[osrf-migration]

Original comment by Alexander Moriarty (Bitbucket: Alexander Moriarty).

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I followed the instructions to install from source https://ignitionrobotics.org/docs/blueprint/install#option-3-source-installation-any-platform- and have the same results.

[osrf-migration]

Original comment by Louise Poubel (Bitbucket: chapulina, GitHub: chapulina).

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I ran ign gazabo -v 4 -s then ign service -l and I see no services listed.

Can you check which versions of the ign service cli you have running:

ign service --versions

If that shows more than 1 version, try using version 7, like:

ign service --force-version 7.X.X -l

[osrf-migration]

Original comment by Alexander Moriarty (Bitbucket: Alexander Moriarty).

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I’ll try to find time to try it again when I’ve got that laptop turned on… I just tried again from a different laptop and ran into #37 (and #41 looks like a duplicate of #37)

Update:
On this laptop, which didn’t have the same error as this issue but the error from #37 and #41

ign service --versions

listed two versions

7.1.0
4.0.0

After running

ign service --force-version 7.1.0 -l

I am able to successfully run ign gazebo -v 3 lights.sd

But I’m not able to run just ign gazebo -v3 or ign gazebo -g -v4

[osrf-migration]

Original comment by Alex Baucom (Bitbucket: Alex Baucom).

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I am also having this exact same issue after following the binary install instructions for the citadel release on Ubuntu 18.04.3

I confirmed that I see the same result as Alexander when running ign gazebo -v 4 -s and then ign service -l. The server appears to start up correctly, but then no services are listed.

If I try to run the gui at all (i.e. ign gazebo shapes.sdf -v 4) I get a black screen and the same message [ign.cc:230] GUI requesting list of world names. The server may be busy downloading resources. Please be patient.over and over until I kill the process.

I have also confirmed that I only show version 8.0.0 when running ign service --versions

Any other debugging suggestions or workarounds I can try?

[osrf-migration]

Original comment by Alex Baucom (Bitbucket: Alex Baucom).

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Okay I may have spoke a bit too soon. I saw the suggestion above about using IGN_IP=127.0.0.1 which I somehow missed earlier and when I exported that to my environment, I was able to launch gazebo. Like Alexander, I also ran into the segmentation fault/rendering window issue, but I was able to fully launch using the workaround specified here. So it looks like maybe just adding that environment variable to my .bashrc or something should resolve this particular problem for me (at least for now I think).

‌

[devashishRaj]

i am facing same on mac but on wsl2 using ubuntu 22 i fixed this issue via enabling multicast .
https://docs.ros.org/en/rolling/How-To-Guides/Installation-Troubleshooting.html