moonfire-nvr/guide/troubleshooting.md

Troubleshooting

Logs

While Moonfire NVR is running, logs will be written to stderr.

• When running moonfire-nvr config, you typically should redirect stderr to a text file to avoid poor interaction between the interactive stdout output and the logging.
• When running through systemd, stderr will be redirected to the journal. Try sudo journalctl --unit moonfire-nvr to view the logs. You also likely want to set MOONFIRE_FORMAT=google-systemd to format logs as expected by systemd.

Logging options are controlled by environmental variables:

• MOONFIRE_LOG controls the log level. Its format is similar to the RUST_LOG variable used by the env-logger crate. MOONFIRE_LOG=info is the default. MOONFIRE_LOG=info,moonfire_nvr=debug gives more detailed logging of the moonfire_nvr crate itself.
• MOONFIRE_FORMAT selects the output format. The two options currently accepted are google (the default, like the Google glog package) and google-systemd (a variation for better systemd compatibility).

Problems

Error: pts not monotonically increasing; got 26615520 then 26539470

If your streams cut out with an error message like this one, there are a couple possibilities.

One is that your camera outputs B frames. If you believe this is the case, file a feature request; Moonfire NVR currently doesn't support B frames. You may be able to configure your camera to disable B frames in the meantime.

A more subtle problem occurs in cameras such as the Dahua Starlight series when the following is true:

• Audio is enabled (thus a single RTSP session has two streams).
• The camera's clock changes abruptly. Note that many cameras use SNTP rather than NTP to adjust time, so they consistently step time rather than slew it.
• They send RTCP Sender Reports (these include the NTP time).

Moonfire NVR currently uses the ffmpeg library to talk to the cameras. ffmpeg doesn't properly support this situation. It uses the NTP time to adjust the PTS and DTS, and thus experiences jumps forward and backward. The forward jumps cause one frame to be artificially lengthened. The backward jumps create an impossible situation which causes Moonfire NVR to abort the session and retry.

In the long term, Moonfire NVR will likely implement its own RTSP support.

In the short term, you can use either of two workarounds:

• Disable audio in the camera settings. Note that Moonfire NVR doesn't yet support recording audio anyway.
• Disable time adjustment. You'll likely want to disable in-picture timestamps as well as they will become untrustworthy.

moonfire-nvr config displays garbage

This happens if your machine is configured to a non-UTF-8 locale, due to gyscos/Cursive#13. As a workaround, type export LC_ALL=en_US.UTF-8 prior to running moonfire-nvr config.