VDIFPacker — Troubleshooting

No data written to disk

Cause: Recording has not been started via the message queue, or output_type does not include "disk".

Resolution: Check that mq_control matches the queue name used by the Field System Interface. Verify output_type in the active configuration via ?sensor-value current-config.


UDP frames not received by jive5ab

Cause: udp.dest_ip does not point to the jive5ab host, or jive5ab is not listening on udp.dest_port.

Resolution: Confirm udp.dest_ip and udp.dest_port in the configuration. On the jive5ab host verify the service is running and listening:

ss -ulnp | grep 4991

recording-state stuck at recording after observation ends

Cause: The Field System Interface did not send a stop message to the POSIX queue, or the queue name is mismatched.

Resolution: Check that mq_control in the vdif_packer config matches mq_control_name in the Field System Interface config. Restart the pipeline to clear the queue.


High heap drop rate

Cause: The vdif_packer binary cannot keep up with the input data rate, or the DADA ring buffer is too small.

Resolution: Check CPU pinning and reduce nfft or naccumulate to lower processing load. Verify that no other process is competing for the input NIC.


vdif-channel-mean sensor shows unexpected values

Cause: The DDC output levels are outside the expected range (e.g., due to ADC clipping or incorrect attenuation).

Resolution: Check the DBBC attenuator settings via the Field System Interface. Adjust digitizer_threshold if automatic level control is enabled.


Log locations

Log

Location

Container stdout

docker logs vdif_packer

vdif_packer binary output

included in container stdout

Signal level monitoring

Grafana → visualizations panel

Waterfall spectrogram

Grafana → waterfall panel