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SCAT: Signaling Collection and Analysis Tool
GNU General Public License v2.0
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Packet length mismatch #110

Open saki92 opened 1 month ago

saki92 commented 1 month ago

SUMMARY I save the logs in .qmdl format from Sierra EM9191 USB module. Then when parsing it with scat, there are a lot of packet length mismatch and CRC mismatch warning messages

STEPS TO REPRODUCE Steps to reproduce the behavior:

  1. Save logs from Sierra USB modem with sudo ./bin/dm-loggerrpi -p /dev/ttyUSB1 -o log.qmdl. Google drive link to log file. The tool is available in MBPL tools package from sierra website.
  2. Copy it to your local machine where SCAT is installed.
  3. Run SCAT with arguments scat -t qc -d log.qmdl --layer "ip,nas,rrc,pdcp,rlc,mac"
  4. See so many length mismatch errors scat-out.log

EXPECTED and ACTUAL RESULT I expect to see at least some MAC layer messages and no warnings in parsing the logs.

ENVIRONMENT

ADDITIONAL INFORMATION Work flow for logging: I started the logging tool, switch on modem via AT command, let the modem connect to network and establish PDU session (5G). Then switch off modem via AT and stop logging.

peremen commented 1 month ago

You can temporarily disable the CRC check using --disable-crc-check option, but that only hides the root cause of the problem and my test with the qmdl file seemed to produce another set of error. Let me look it.