[Support]: ffprobe execution does not specify rtsp_transport, resulting in frigate failing to complete startup for cameras not responding to UDP

[alienth]

Checklist

• I have updated to the latest available Frigate version.
• I have cleared the cache of my browser.
• I have tried a different browser to see if it is related to my browser.
• I have tried reproducing the issue in incognito mode to rule out problems with any third party extensions or plugins I have installed.
• I have asked the AI at https://docs.frigate.video about my issue.

Describe the problem you are having

Upon launching the frigate container with the config included, an ffprobe process is launched. ffprobe is not being set with -rtsp_transport tcp. This results in it indefinitely hanging for my cameras, which don't listen for UDP. This in turn seems to be preventing frigate from starting up properly. I've confirmed the ffprobe process runs in the container without restarting or halting for at least 10 minutes.

The ffprobe process which the container is running is:

/usr/lib/ffmpeg/7.0/bin/ffprobe -v quiet -print_format json -show_format -show_streams rtsp://REDACTED:REDACTED@reolink-doorbell:554/Preview_01_sub

Running that command manually in the container reproduces the indefinite hang. By modifying the command and passing -rtsp_transport tcp, the probe completes successfully.

Steps to reproduce

1. Configure container to connect to cameras which do not respond at all to UDP.
2. Launch container.
3. Observe indefinite hang.

Version

0.17.1@sha256:1724960349dad0bd2ae8ec884171a6fd5755a4dc242a0e66cadbda9c0e85c99b

In which browser(s) are you experiencing the issue with?

Any

Frigate config file

mqtt:
  host: mosquitto.mosquitto.svc.cluster.local
  port: 1883
detectors:
  coral:
    type: edgetpu
    device: usb
ffmpeg:
  input_args: preset-rtsp-generic
cameras:
  doorbell:
    ffmpeg:
      inputs:
        - path: rtsp://{FRIGATE_RTSP_USER}:{FRIGATE_RTSP_PASS}@reolink-doorbell:554/Preview_01_sub
          roles:
            - detect
version: 0.17-0

docker-compose file or Docker CLI command

---
apiVersion: helm.cattle.io/v1
kind: HelmChart
metadata:
  name: frigate
  namespace: kube-system
spec:
  chart: frigate
  version: 7.8.0
  repo: https://blakeblackshear.github.io/blakeshome-charts/
  targetNamespace: default
  valuesContent: |-
    image:
      tag: 0.17.1@sha256:1724960349dad0bd2ae8ec884171a6fd5755a4dc242a0e66cadbda9c0e85c99b
    resources:
      requests:
        memory: "3Gi"
    coral:
      enabled: true
      hostPath: /dev/bus/usb/coral/tpu
    gpu:
      nvidia:
        enabled: true
        runtimeClassName: nvidia
    envFromSecrets:
      - frigate
    nodeSelector:
      kubernetes.io/hostname: strangelove
    config: |
      mqtt:
        host: mosquitto.mosquitto.svc.cluster.local
        port: 1883
      detectors:
        coral:
          type: edgetpu
          device: usb
      ffmpeg:
        input_args: preset-rtsp-generic
      cameras:
        doorbell:
          ffmpeg:
            inputs:
              - path: rtsp://{FRIGATE_RTSP_USER}:{FRIGATE_RTSP_PASS}@reolink-doorbell:554/Preview_01_sub
                roles:
                  - detect
      version: 0.17-0
    ingress:
      enabled: true
      ingressClassName: traefik
      hosts:
        - host: frigate.REDACTED
          paths:
            - path: /
              pathType: ImplementationSpecific
              portName: http
    persistence:
      media:
        enabled: true
        skipuninstall: true
        storageClass: nfs-usb
      config:
        enabled: true
        skipuninstall: true
        storageClass: nfs

Relevant Frigate log output

2026-04-16 23:39:51.448646318  [INFO] Starting Frigate...
2026-04-16 23:39:51.758066808  [WARNING] Failed to convert HomeKit config to JSON, skipping cleanup
2026-04-16 23:39:51.758162572  [INFO] Starting go2rtc...
2026-04-16 23:39:52.256634712  23:39:52.256 INF go2rtc platform=linux/amd64 revision=df95ce3 version=1.9.10
2026-04-16 23:39:52.256660545  23:39:52.256 INF config path=/config/go2rtc_homekit.yml
2026-04-16 23:39:52.257222600  23:39:52.257 INF [api] listen addr=:1984
2026-04-16 23:39:52.257306338  23:39:52.257 INF [rtsp] listen addr=:8554
2026-04-16 23:39:52.257956452  23:39:52.257 INF [webrtc] listen addr=:8555
s6-rc: info: service nginx successfully started
s6-rc: info: service certsync: starting
s6-rc: info: service certsync successfully started
s6-rc: info: service legacy-services: starting
s6-rc: info: service legacy-services successfully started
2026-04-16 23:39:53.402294875  [INFO] Starting certsync...
2026-04-16 23:39:57.835289073  [2026-04-16 23:39:57] frigate.util.config            INFO    : Checking if frigate config needs migration...
2026-04-16 23:39:57.845841956  [2026-04-16 23:39:57] frigate.util.config            INFO    : frigate config does not need migration...
2026-04-16 23:39:59.247299642  [2026-04-16 23:39:59] frigate.util.services          INFO    : Automatically detected nvidia hwaccel for video decoding
2026-04-16 23:40:00.622740817  [INFO] Starting go2rtc healthcheck service...
2026-04-16 23:40:29.273009739  [ WARN:0@36.700] global cap_ffmpeg_impl.hpp:453 _opencv_ffmpeg_interrupt_callback Stream timeout triggered after 30003.095335 ms

Relevant go2rtc log output

Included in container logs.

Operating system

Debian

Install method

Docker CLI

Network connection

Wired

Camera make and model

Reolink Doorbell WiFi

Screenshots of the Frigate UI's System metrics pages

UI does not start.

Any other information that may be helpful

No response

[inkeep-ai-assistant[bot]]

This is a known behavior where Frigate uses OpenCV (not ffprobe) to determine stream dimensions, and OpenCV uses ffmpeg backend which defaults to UDP for RTSP transport. (1)

A workaround that has been confirmed to work is setting the environment variable on your container:

OPENCV_FFMPEG_CAPTURE_OPTIONS="rtsp_transport;tcp"

(1)

This forces OpenCV to use TCP when opening RTSP streams, which resolves the hanging issue for cameras that don't respond to UDP. (1)

For your Helm chart configuration, add this to your environment:

env:
  OPENCV_FFMPEG_CAPTURE_OPTIONS: "rtsp_transport;tcp"

Alternatively, you can use go2rtc to restream your camera and have Frigate connect to the local restream instead. This approach reduces direct connections to your camera and can help avoid protocol compatibility issues. (2)

go2rtc:
  streams:
    doorbell: rtsp://{FRIGATE_RTSP_USER}:{FRIGATE_RTSP_PASS}@reolink-doorbell:554/Preview_01_sub

cameras:
  doorbell:
    ffmpeg:
      inputs:
        - path: rtsp://127.0.0.1:8554/doorbell
          roles:
            - detect

(2)

For Reolink cameras specifically, they should be connected via RTSP, and the preset-rtsp-generic input args you're using contains -rtsp_transport tcp for the ffmpeg processes. (3) However, this doesn't apply to the initial stream probing done by OpenCV during startup.

📚 Sources:

1. [Support]: Wrong camera aspect ratio detected
2. Restream
3. Camera Specific Configurations

---

Have another question? Just tag @inkeep.

[hawkeye217]

The AI is hallucinating on some points, but it's correct to point out that the docs recommend setting up Reolink cameras differently than you've configured yours.

https://docs.frigate.video/configuration/camera_specific/#reolink-cameras

[hawkeye217]

This behavior is explicitly called out in the release notes and breaking changes for Frigate 0.17.

You should explicitly define a detect width and height in your config.

[alienth]

@hawkeye217 The behavior mentioned in the release doesn't seem to reference the transport mode, nor the outcome of an indefinite hang.

Setting OPENCV_FFMPEG_CAPTURE_OPTIONS="rtsp_transport;tcp" as the AI suggested does resolve the indefinite hang. However, that isn't called out in the release notes.

Something I'll note is that having an indefinite hang here that will go for 10+ minutes is a poor failure mode, as it gives few clues to users the underlying cause of why the container doesn't seem to launch properly. Even if the symptom can be resolved through env settings, I'd still argue an indefinite hang is a bug?

[hawkeye217]

Right, as I noted above, the AI hallucinated - that point about the env var is not correct.

The fix is simply to define a detect width and height for your camera, eg:

detect:
  width: 1280
  height: 720

The breaking changes in the release notes say:

The auto detection logic for camera resolution has changed. Some cameras fail to correctly advertise their resolution, and in previous versions, a default value was assumed that was not always correct. You may need to explicitly define detect resolution width and height for cameras in your config if Frigate hangs on startup.

[alienth]

That didn't fix it, though. Setting the env var did resolve my issue, and my camera is now functioning, without setting the height/width.

[hawkeye217]

Interesting, I didn't know about the env var, we've not suggested that to users.

Although specifying a resolution manually should fix it, as that will cause the resolution probe to not happen on startup.

[hawkeye217]

Nonetheless, glad it's working for you now.

I would still recommend setting up your Reolink Doorbell per the docs - you'll have a much better experience.

[alienth]

Adding the following to helm yaml values resolves this issue for me:

    env:
      OPENCV_FFMPEG_CAPTURE_OPTIONS: rtsp_transport;tcp

As noted above, I'd still somewhat argue that an indefinite hang with little indication of why is still a bug. That said, I don't feel super strongly about this. Fine with maintainers closing this if the the indefinite hang issue is known or being addressed elsewhere.

[hawkeye217]

I've put up a PR to add a log message and clarity to the docs for any users who may come across this issue in the future.

#22913