Hi nishan_perera,
Like @chanfoli wrote, this caused by the forwarding syslog server. You can fix it in Splunk by using a transformation.
It should be done on the indexer(s). You will need two files, props.conf and transforms.conf, both of them in $SPLUNK_HOME/etc/system/local. I will assume that this is the only data that is coming from the syslog server, and that the syslog server is named syslogServer (for my example).
props.conf
[host::syslogServer]
TRANSFORMS-t1=rename_host
transforms.conf
[rename_host]
REGEX=Original Address\=(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})
DEST_KEY=MetaData:Host
FORMAT=host::$1
This transformation will be applied to data from the host as it is indexed. Data already in the index will not be affected.
cheers, MuS
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