Configure admission rules to prefilter searches
Admission rules let you filter out searches automatically before they start, based on a predicate (condition) that you define. If a search meets the specified condition, the search is not executed.
You can use admission rules to prevent the execution of rogue searches, such as poorly written and potentially harmful searches that might consume an excessive amount of resources and interfere with critical search workloads. For example, you can create a rule to filter out wildcard searches that target all indexes, or filter out searches in the
alltime time range.
You can also use admission rules to set up time-bound access to searches for roles, users, apps and so on. For example, you can create a rule that filters out all ad hoc searches from a certain role during peak business days, but allows the same role to run searches on weekends.
Admission rules have no explicit ordering. All admission rules are evaluated when a search is dispatched. If a search meets the conditions of a rule, the rule takes effect before the search is executed. If a search is already running, and you create a new admission rule that applies to that search, the running search is not affected by the new rule.
Admission rules are enabled by default for the
sc_admin role. You can create a maximum of 100 admission rules per Splunk cloud deployment.
Create an admission rule using Splunk Web
To create and edit admission rules, a user's role must have the
To create an admission rule using Splunk Web:
- In Splunk Web, click Settings > Workload Management.
- Click Add Admission Rule.
- Define the following fields to configure a new admission rule:
Field Action Name Specify the name of the admission rule. Predicate (Condition) Specify a predicate (condition) that must match to trigger this rule. The predicate syntax is <type>=<value> with optional AND, OR, NOT, (). For example,
app=search AND role=powertriggers all searches belonging to both the Search app and the power role.
Valid predicate types are
For supported predicate values, see Predicate type values on this page.
In complex predicates,
NOToperators must be upper case. Lower case is not supported.
Schedule (Optional) Set a schedule for the admission rule. The schedule determines the time period during which the rule is valid.
If set to
Always On(the default), the rule remains valid indefinitely and does not expire.
If set to
Time Range, the rule is valid during the specified time range only and expires when the time range ends.
If set to
Every Week, or
Every Month, the rule becomes valid on a recurring basis during the specified time range every day, on the specified days of the week, or on the specified days of the month.
The schedule time for an admission rule is based on the system timezone, regardless of the timezone set for an individual user in the UI.
Action Admission rules currently support the default
Filter searchaction only.
User Message Enter a custom message that notifies the end user when a search triggers the admission rule action. For example, "This search meets specified admission rule conditions. The search was not executed."
If an ad hoc search triggers the rule action, the custom message appears beneath the search bar in the Search and Reporting app. If a scheduled search triggers the action, a default message appears in
- Click Submit.
Enable admission rules
The admission rules feature must be enabled for any existing admission rules to apply to searches. In Splunk Cloud, the admission rules feature is enabled for the
sc_admin role by default and cannot be disabled.
Enable individual admission rules
You can enable or disable individual admission rules. This lets you create and save multiple different admission rules and deploy them as needed. Individual admission rules are enabled by default when you create them. Disabled admission rules are not evaluated and have no impact on search execution.
To enable or disable an individual admission rule:
- In Splunk Web, click Settings > Workload Management > Admission Rules.
- In the Status column, toggle the switch to enable or disable the individual admission rule.
Example admission rules
The following examples show how you can define admission rules to filter out searches based on your use case objectives.
Example 1: Stop wildcard searches
The following rule excludes data model acceleration searches that use
index=* from the filter:
index=* AND (NOT search_type=datamodel_acceleration)
Example 2: Stop all-time searches
Some monitoring searches use the
alltime time range. The following rule excludes those searches from the filter:
search_time_range=alltime AND (NOT role=sc_admin) AND (NOT app=splunk_instance_monitoring)
The "View index inheritance for roles" feature also uses an
alltime search. You can exclude users or roles that need to view indexes from the filter. The above rule excludes the
Example 3: Do not allow certain users to run ad hoc searches at peak hours
search_type=adhoc AND role=new_users
After you define the admission rule predicate, set the schedule for the rule, specifying the time range that corresponds to your peak hours.
For more admission rule use case examples, see Scenario 3: Create admission rules to prefilter searches.
Configure workload rules
Manually assign searches to workload pools
This documentation applies to the following versions of Splunk Cloud™: 8.1.2011, 8.1.2012 (latest FedRAMP release), 8.1.2101, 8.1.2103, 8.2.2104