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Optimize Nested Search

Path Finder

This search is slow (our dns logs are large).

index=winlogs sourcetype=dns | eval dottedquestion=replace(replace(questionname,"\(\d+\)","."),"\.(.*)\.","\1") | search [| inputlookup baddomains | return 10000 dottedquestion=Domain]

Outside of shrinking the time window (I am not interested in going under 24 hours) is there anyway to optimize it? The baddomains list is very small (<1000)

Thank you in advance.

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Re: Optimize Nested Search

Motivator

Can you share some sample pattern for questionname field?

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Re: Optimize Nested Search

Path Finder

Sure - apparently ms logs dns in “pascal style” string format. Showing the length of each next section in parens ending in (0).

(12)somecomputer(6)domain(3)com(0)

Defined in 4.1.2 of the RFC1035:
https://tools.ietf.org/html/rfc1035

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Re: Optimize Nested Search

Builder

If you're not counting and just looking for presence, try a "dedup dottedquestion" just before the | search.

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Re: Optimize Nested Search

Motivator

Probably join might help you.

index=winlogs sourcetype=dns 
| eval Domain=replace(replace(questionname,"\(\d+\)","."),"\.(.*)\.","\1") 
| join type=inner Domain 
    [| inputlookup baddomains 
    | table Domain]

Also, if it's ad-hoc search, Run in 'Fast Mode' instead of 'Verbose Mode'.

0 Karma