My team is currently experiencing an issue with duplicate logs being produced in NXLog's outbound syslog feed. NXLog is reading from a flat file and sending a syslog feed to another machine for processing. Running a TCPdump for the incoming data on that second machine shows that multiple copies of the same log are being sent by NXlog. Moreover, the duplicates are not sent sequentially, but instead are sent almost exactly 5 minutes apart as show by five minute gaps between the "EventReceivedTime" syslog header values. We have reviewed the flat file and confirmed that it does not produce the duplicates, and thus must be related to the configuration of NXLog and the way it reads the flat file. I'd appreciate any insight others might have on what is causing this problem.

The NXLog configuration is as follows:

Panic Soft #NoFreeOnExit TRUE

define ROOT D:\NX Log\Program Files define CERTDIR %ROOT%\cert define CONFDIR %ROOT%\conf define LOGDIR %ROOT%\data define LOGFILE %LOGDIR%\nxlog.log LogFile %LOGFILE%

Moduledir %ROOT%\modules CacheDir %ROOT%\data Pidfile %ROOT%\data\nxlog.pid SpoolDir %ROOT%\data

<Extension _syslog> Module xm_syslog </Extension>

<Extension _charconv> Module xm_charconv AutodetectCharsets iso8859-2, utf-8, utf-16, utf-32 </Extension>

<Extension _exec> Module xm_exec </Extension>

<Extension _fileop> Module xm_fileop

# Check the size of our log file hourly, rotate if larger than 5MB
<Schedule>
    Every   1 hour
    Exec    if (file_exists('%LOGFILE%') and \
               (file_size('%LOGFILE%') >= 5M)) \
                file_cycle('%LOGFILE%', 8);
</Schedule>

# Rotate our log file every week on Sunday at midnight
<Schedule>
    When    @weekly
    Exec    if file_exists('%LOGFILE%') file_cycle('%LOGFILE%', 8);
</Schedule>

</Extension>

<Input in> Module im_file File "D:[Ingested File Path].cef" InputType LineBased SavePos TRUE ReadFromLast TRUE PollInterval 1 </Input>

<Processor norepeat> Module pm_norepeat </Processor>

<Output out> Module om_ssl Host [Second Machine IP] Port 515 Exec to_syslog_ietf();

Allows using self-signed certificates

AllowUntrusted  FALSE

Certificate from the peer host

CAFile          D:\[CA File Path].pem

Certificate file

CertFile        D:\[Certificate File Path].pem

Keypair file

CertKeyFile     D:\[Key File Path].pem

</Output>

<Route sitecollector> Path in => norepeat => out </Route>