When attempting to add probes to a request.cfg, on a hub robot, so that those probes will be deployed by a local distsrv upon restart, sometimes the deployment may fail.
In the controller.log the following error will be seen shortly after startup:
Controller: probe deploy (distsrv) - verify connection - unable to contact distsrv, rc=4 (not found)
Controller: probe deploy (distsrv) - complete - failed (rc=4 (not found))
Controller: probe deploy - failed, rc=4 (not found)
UIM 8.x or 9.x
Robot 7.93 or higher
Hub and distsrv probes installed on the robot
Sometimes the distsrv probe has not yet started by the time the controller attempts to request the packages. This happens only on a hub robot; normal robots will request their packages from their local hub's distsrv, which should already be up and running when the request is made.
However, on a hub robot, the request is made to the distsrv running on the same machine, and this may take longer to start up on a hub vs. a normal robot.
You can add the following key in robot.cfg in the main (controller) section:
max_probe_deploy_attempt = 20
Normally this defaults to 5 when the key is not present, and it's possible that isn't enough - raising this to a higher value will cause the deployment to retry more times and allow the distsrv longer to start.