Curtiss-Wright SSR/CHS/001/B, Руководство пользователя, Страница: 29 / 34

C
HAPTER
3: O
PERATING A MULTI
-
ROLE RECORDER
25
Power loss while recording
If the recorder loses power while recording, the File Allocation Table (FAT) does not have time to be updated.
When opening the files in Wireshark, an error is displayed, even though no packets are actually missing or
corrupted. To clear the error message, open the PCAP file in Wireshark and click Save As. The file is now
corrected.
Efficient space management
Using the EVENT button instead of switching START/STOP many times in succession can save disc space.
Every time recording is stopped and started again, a new file is opened regardless of whether the previous file was
full before it was closed. This leads to inefficient use of space on the media. For example, if the recorded data
occupies only 1 MB, the full 120 MB file is allocated to this recording session. To overcome this, rather than using
the START/STOP mechanism to delineate key moments during the recording session, it is more efficient to inject
event packets in the recorded data by pressing the EVENT button.
You can monitor the memory usage and be warned when the media is close to becoming completely full. A multi-
role recorder supports a freeSpaceWarningLimit SNMP variable. When the amount of free memory available
on the media falls below the threshold, the multi-role recorder issues a blinking warning notification on the display,
allowing you to insert a fresh memory media if necessary. If the freeSpaceWarningLimit variable is set to zero,
no warning is issued.
Filenames
Each filename is automatically generated by the multi-role recorder during the formatting process. Filenames have
the generalized format <ssss_ffff.cap>, or <DATA_sss_fff.cap> on older multi-role recorders, where:
• ssss: is a session number (0-9999). This number increments when the multi-role recorder starts using the
memory media, that is, when the media is mounted in the multi-role recorder. The media is mounted when it is
inserted in the multi-role recorder or after a power-cycle.
• ffff: is a file number (0-9999). This number resets to zero on the start of a new session, that is, if
0123_0456.cap is the last file in a session, the next file is 0124_0000.cap.