HTTP request fails intermittently, but works via command line curl

[themightyoarfish]

ouster-sdk/ouster_client/src/sensor_http.cpp

Line 18 in 225053d

auto fwjson = http_client->get("api/v1/system/firmware", timeout_sec);

This line in the client sometimes fails for us with this error

  what():  CurlClient::execute_request failed for the url: [http://os-122422000616.local/api/v1/system/firmware] with the error message: Couldn't connect to server

When SensorHTTP::create() is invoked. Simply retrying a few times makes it go away. Meanwhile I can never reproduce this behaviour when just using curl on the command line in a loop

while true; do curl --request GET http://os-122422000616.local/api/v1/system/firmware && echo "result was $?"; done

(always successful).

This has happened with several different rev7 devices, and I'm not sure how to troubleshoot. The scanners work normally once connected.

Any advice on how to investigate?

I have not yes tried with current master, as it has introduced some install issues wrt to the version we're using, but the HTTP code is identical.

[themightyoarfish]

Any help here? Am i the only one experiencing this?

[matthew-lidar]

What timeout_sec value are you using? We have found that some systems or network configurations need a timeout of at least a few seconds.

It is also worth noting that the sensor sometimes does not respond to HTTP requests quickly while starting up or re-initializing, requiring a much larger timeout in these cases.

[themightyoarfish]

We are using a 10 second timeout, but it terminates right away, without waiting for 10 seconds as far as i can tell