In the Splunk Processing Language (SPL), terms separated by a space are treated with an implicit AND operator. The search index=security Error Fail is functionally equivalent to index=security Error AND Fail. This query will return only the events from the "security" index that contain both the term "Error" and the term "Fail". Splunk's keyword searching is case-insensitive by default, so it will match "error", "Error", "fail", "Fail", etc. This precisely fulfills the requirement to find events containing both specified terms.

B. index=security error OR fail This uses the OR operator, which finds events containing either "error" or "fail", not necessarily both.
C. index=security “error failure” The double quotes specify a search for the exact literal phrase "error failure", which is too restrictive and not what was requested.
D. index=security NOT error NOT fail This uses the NOT operator to explicitly exclude events containing "error" or "fail", which is the opposite of the desired outcome.

1. Splunk Enterprise

Search Manual

Version 9.2.1

"Use boolean expressions":

Section: The AND operator: "The AND operator is implied between terms. For example

the search web error is the same as web AND error. This search retrieves events that contain both the term web and the term error." This directly supports the logic for answer A.

Section: The OR operator: "The OR operator is used to search for events that contain either of the specified terms." This confirms why option B is incorrect.

Section: The NOT operator: "The NOT operator is used to exclude events that contain a specific term." This confirms why option D is incorrect.

2. Splunk Enterprise

Search Manual

Version 9.2.1

"Search with phrases":

Section: Search for phrases: "To search for a phrase

enclose the phrase in double quotation marks. For example

to search for out of memory you would specify "out of memory"." This confirms why option C is incorrect as it searches for a specific phrase

not individual terms.

3. Splunk Enterprise

Search Manual

Version 9.2.1

"How search works":

Section: How Splunk software processes searches: "Keyword searches are case-insensitive." This confirms that Error and Fail will match all case variations of the words.