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How to create rex to extract field?

Harish2
Path Finder

From here i need to extarct the identification=MLAS, MLA, LAS and VAM
My sample logs:
[12/12/21] 12:10:112 GMT] I6789HIOO applicattion authenticationid=100| |35467577889999| |67775-ghhgfrt-6788h-7667788; clientid="7689-jhgg-8765r-kkjggt"; app=" "; QueryLetter="yard=MS&identification=MLAS&timeRange=EVERYDAY&timePeriod=MINUTES

[12/12/21] 12:10:112 GMT] I6789HIOO applicattion authenticationid=100| |35467577889999| |67775-ghhgfrt-6788h-7667788; clientid="7689-jhgg-8765r-kkjggt"; app=" "; QueryLetter="yard=MS&identification=MLA&timeRange=EVERYDAY&timePeriod=MINUTES

[12/12/21] 12:10:112 GMT] I6789HIOO applicattion authenticationid=100| |35467577889999| |67775-ghhgfrt-6788h-7667788; clientid="7689-jhgg-8765r-kkjggt"; app=" "; QueryLetter="yard=MS&identification=LAS&timeRange=EVERYDAY&timePeriod=MINUTES

[12/12/21] 12:10:112 GMT] I6789HIOO applicattion authenticationid=100| |35467577889999| |67775-ghhgfrt-6788h-7667788; clientid="7689-jhgg-8765r-kkjggt"; app=" "; QueryLetter="yard=MS&identification=VAM&timeRange=EVERYDAY&timePeriod=MINUTES

in my selected fileds or intresting fileds  indeentification fileds  should appear has below:
MLAS
MLA
LAS 
VAM

Labels (1)
0 Karma
1 Solution

richgalloway
SplunkTrust
SplunkTrust

The rex command works for me.

| rex "identification=(?<identification>\w+)"
---
If this reply helps you, Karma would be appreciated.

View solution in original post

yuanliu
SplunkTrust
SplunkTrust

Are posted logs raw events?  Is there some settings in your sourcetype (props.conf) that prevents automatic extraction of the fields you wanted?  Because the field names and values are connected by equal sign, Splunk should have already extracted them.

Here is an emulation of your samples:

 

| makeresults
| fields - _time
| eval data = split("[12/12/21] 12:10:112 GMT] I6789HIOO applicattion authenticationid=100| |35467577889999| |67775-ghhgfrt-6788h-7667788; clientid=\"7689-jhgg-8765r-kkjggt\"; app=\" \"; QueryLetter=\"yard=MS&identification=MLAS&timeRange=EVERYDAY&timePeriod=MINUTES
[12/12/21] 12:10:112 GMT] I6789HIOO applicattion authenticationid=100| |35467577889999| |67775-ghhgfrt-6788h-7667788; clientid=\"7689-jhgg-8765r-kkjggt\"; app=\" \"; QueryLetter=\"yard=MS&identification=MLA&timeRange=EVERYDAY&timePeriod=MINUTES
[12/12/21] 12:10:112 GMT] I6789HIOO applicattion authenticationid=100| |35467577889999| |67775-ghhgfrt-6788h-7667788; clientid=\"7689-jhgg-8765r-kkjggt\"; app=\" \"; QueryLetter=\"yard=MS&identification=LAS&timeRange=EVERYDAY&timePeriod=MINUTES
[12/12/21] 12:10:112 GMT] I6789HIOO applicattion authenticationid=100| |35467577889999| |67775-ghhgfrt-6788h-7667788; clientid=\"7689-jhgg-8765r-kkjggt\"; app=\" \"; QueryLetter=\"yard=MS&identification=VAM&timeRange=EVERYDAY&timePeriod=MINUTES", "
")
| mvexpand data
| rename data AS _raw
| extract

 

 These are the fields extracted:

QueryLetterappauthenticationidclientididentificationtimePeriodtimeRange
"yard=MS 100| |35467577889999| |67775-ghhgfrt-6788h-76677887689-jhgg-8765r-kkjggtMLASMINUTESEVERYDAY
"yard=MS 100| |35467577889999| |67775-ghhgfrt-6788h-76677887689-jhgg-8765r-kkjggtMLAMINUTESEVERYDAY
"yard=MS 100| |35467577889999| |67775-ghhgfrt-6788h-76677887689-jhgg-8765r-kkjggtLASMINUTESEVERYDAY
"yard=MS 100| |35467577889999| |67775-ghhgfrt-6788h-76677887689-jhgg-8765r-kkjggtVAMMINUTESEVERYDAY
0 Karma

richgalloway
SplunkTrust
SplunkTrust

The rex command works for me.

| rex "identification=(?<identification>\w+)"
---
If this reply helps you, Karma would be appreciated.

Harish2
Path Finder

Hi @richgalloway 
it worked, thank you

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