How to prevent data duplication on a csv file ?

[dm1]

I have a scheduled search that outputs the results every 5 minutes using the outputcsv command to local disk. The file is stored with name abc_dns.csv  

index=abc |fields _time _raw |fields - _indextime _sourcetype _subsecond |outputcsv abc_dns

Then I am forwarding that file to an external Indexer

inputs.conf

[monitor:///opt/splunk/var/run/splunk/csv/abc_dns.csv]
index = abc_dns_logs
sourcetype = abc_dns
#crcSalt = <SOURCE>

Below is the props.conf

[abc_dns]
INDEXED_EXTRACTIONS = csv
HEADER_FIELD_LINE_NUMBER = 1
KV_MODE = none
NO_BINARY_CHECK = true
SHOULD_LINEMERGE = false
category = structured
TRANSFORMS-t1 = eliminate_header

transforms.conf

[eliminate_header]
REGEX = ^"_time","_raw"$
DEST_KEY = queue
FORMAT = nullQueue

When I validate the results, I am seeing data is getting duplicated on the external Indexer.

I attempted to add crcSalt = <SOURCE> to check if it makes any difference, which seemed that it did initially, however, afterwhile, I saw data was getting duplicated again. In reality, there is indeed duplicate data in original logs itself, but overall I am actually seeing data from the monitored file is also getting duplicated.

Can anyone please help with this ?

[anilchaithu]

@dm1 

If the csv file generated from the search has duplicate rows, indexer will index them as is. You need to remove duplicates in your search.

Please try this out.

index=abc |fields _time _raw |fields - _indextime _sourcetype _subsecond | dedup field_names* |outputcsv abc_dns

-- Hope this helps