OnSSI NetDVMS Rev 6.5
Logging
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compressed, in which case export log files are also encrypted/compressed and further file
extensions, such as .mzi or .men may appear in export log file names.
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Log File Structures
Most log files generated by NetDVMS use a shared structure complying with the W3C Extended
Log File Format:
Each log file consists of a header and a number of log lines:
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The header outlines the information contained in the log lines.
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The log lines consist of two main parts: the log information itself and an encrypted part.
The encrypted part makes it possible—through decryption and comparison—to assert that
a log file has not been tampered with.
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Integrity Checks and Possible Error Messages
Log files are subjected to an integrity check once every 24 hours. The result of the integrity check
is automatically written to a file named according to the structure LogCheck_YYYYMMDD.log, e.g.
LogCheck_20070615.log.
The log check file is by default placed in the folder containing the NetDVMS software.
Any inconsistencies will be reported in the form of error messages written in the log check file.
The following table lists possible error messages (other, non-error, messages may also appear in
the log check file):
Error Message
Description
”Log integrity information was not
found. Log integrity can't be
guaranteed.”
The log file could not be checked for
integrity.
”Log information does not match
integrity information. Log
integrity can't be guaranteed.”
The log file exists, but does not contain the
expected information. Thus, log integrity
cannot be guaranteed.
”[Log file name] not found.”
The log file was not present.
”[Log file name] is empty.”
The log file was present, but empty.
”Last line changed/removed in
[log file name].”
The last line of the log file did not match
validation criteria.
”Encrypted data missing in [log
file name] near line [#].”
The encrypted part of the log line in
question was not present.
