# RMW_IMPLEMENTATION not set for ros2

Source: https://forum.modalai.com/topic/2884/rmw_implementation-not-set-for-ros2
Category: VOXL SDK and Software (https://forum.modalai.com/category/47/voxl-sdk-and-software)
Tags: ros
Posted: 2023-11-21 04:30:41 UTC by Kyuhyong You
Replies: 1 · Views: 1205

## Kyuhyong You · 2023-11-21 04:30:41 UTC

Hello,

I just upgraded my voxl2 with the latest sdk 1.1.0 and apt installed ros2 relate packages as follows
```
sudo apt install voxl-ros2-foxy
$ sudo apt install voxl-microdds-agent
$ sudo apt install voxl-mpa-to-ros2
$ pip3 install netifaces
$ pip3 install pyyaml
```

After `source /opt/ros/foxy/setup.bash` and tried to run ros2 topic and it returns following error.
```
$ ros2 topic list
Unable to get rmw_implementation_identifier, try specifying the implementation to use via the 'RMW_IMPLEMENTATION' environment variable
```

It seems like `RMW_IMPLEMENTATION` not set in the bash.
How to set this variable to run on voxl?

---
Also tried to run configuration as below
```
$ sudo voxl-configure-microdds
Starting Wizard
 
do you want to enable or disable voxl-microdds-agent
factory-enable will also reset the config file back to default
1) disable
2) enable
#? 2
enabling  voxl-microdds-agent systemd service
Created symlink /etc/systemd/system/multi-user.target.wants/voxl-microdds-agent.service → /etc/systemd/system/voxl-microdds-agent.service.
Done configuring voxl-microdds-agent
```
And inspect service returns
```
$ voxl-inspect-services
Scanning services...

 Service Name             |  Enabled  |   Running   |  CPU Usage
-------------------------------------------------------------------
 docker-autorun           | Disabled  | Not Running |  
 modallink-relink         | Disabled  | Not Running |  
 voxl-camera-server       |  Enabled  | Not Running |  
 voxl-cpu-monitor         |  Enabled  |   Running   |     0.7%
 voxl-dfs-server          | Disabled  | Not Running |  
 voxl-feature-tracker     | Disabled  | Not Running |  
 voxl-flow-server         | Disabled  | Not Running |  
 voxl-imu-server          |  Enabled  |   Running   |     6.2%
 voxl-lepton-server       | Disabled  | Not Running |  
 voxl-mavcam-manager      |  Enabled  |   Running   |     0.0%
 voxl-mavlink-server      |  Enabled  |   Running   |     3.4%
 voxl-microdds-agent      |  Enabled  |   Running   |    13.5%
 voxl-modem               | Disabled  | Not Running |  
 voxl-portal              |  Enabled  |   Running   |     0.1%
 voxl-px4-imu-server      | Disabled  | Not Running |  
 voxl-px4                 |  Enabled  |   Running   |    40.2%
 voxl-qvio-server         |  Enabled  |   Running   |     4.2%
 voxl-rangefinder-server  | Disabled  | Not Running |  
 voxl-remote-id           | Disabled  | Not Running |  
 voxl-softap              | Disabled  | Not Running |  
 voxl-static-ip           | Disabled  | Not Running |  
 voxl-streamer            |  Enabled  |   Running   |     0.1%
 voxl-tag-detector        | Disabled  | Not Running |  
 voxl-tflite-server       | Disabled  | Not Running |  
 voxl-time-sync           | Disabled  | Not Running |  
 voxl-uvc-server          | Disabled  | Not Running |  
 voxl-vision-hub          |  Enabled  |   Running   |     1.8%
 voxl-wait-for-fs         |  Enabled  |  Completed  |``
```

## Reply by Kyuhyong You · 2023-11-21 06:26:06 UTC

@Kyuhyong-You 

After reboot this error is magically gone.
now I can see topics 
after `$ ros2 run voxl_mpa_to_ros2 voxl_mpa_to_ros2_node`

then in another terminal on voxl, I see below topics
```
$ ros2 topic list
/fmu/in/obstacle_distance
/fmu/in/offboard_control_mode
/fmu/in/onboard_computer_status
/fmu/in/sensor_optical_flow
/fmu/in/telemetry_status
/fmu/in/trajectory_setpoint
/fmu/in/vehicle_attitude_setpoint
/fmu/in/vehicle_command
/fmu/in/vehicle_mocap_odometry
/fmu/in/vehicle_rates_setpoint
/fmu/in/vehicle_trajectory_bezier
/fmu/in/vehicle_trajectory_waypoint
/fmu/in/vehicle_visual_odometry
/fmu/out/failsafe_flags
/fmu/out/position_setpoint_triplet
/fmu/out/sensor_combined
/fmu/out/timesync_status
/fmu/out/vehicle_attitude
/fmu/out/vehicle_control_mode
/fmu/out/vehicle_local_position
/fmu/out/vehicle_odometry
/fmu/out/vehicle_status
/parameter_events
/rosout
```