Hi,
Splunk Cloud API url will be different but 8089 will only be used to access the API like below:
Use the following URL for single-instance managed deployments.
https://.cloud.splunk.com:8089
Use the following URL for clustered deployments. If necessary, submit a support case to open port 8089 on your deployment.
https://.splunkcloud.com:8089
Self-service Splunk Cloud deployments
https://input-.cloud.splunk.com:8089
Also there are limitations on using Cloud API, you can not do :
Modifying configuration of deployment servers and client configurations and distributed components (indexers, search heads, clustering)
Restarting a Splunk Cloud deployment
Executing debug commands
Installing apps and modifying app configurations
rest searches and queries can be run via cloud API of Splunk.
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