My instance of Splunk currently has 9.4 TB of disk for indexing. We have 360GB per day being indexed and I can't increase the disk size to support this daily indexing.
I need to clean up indexed events from January 2019 through July 2019.
Can someone tell me how to do it and which command to use?
I would suggest you to read about archiving, this could be a better way to safely free some disk space, not losing permanently all data you have indexed before: https://docs.splunk.com/Documentation/Splunk/7.3.1/Indexer/Setaretirementandarchivingpolicy
Using a correct archiving and retirement policy can help you to remove or backup old indexed data, since you can choose to archive frozen buckets or to remove them. You just need to set when you want a bucket to turn to frozen.
If the size of your disk is a limiting factor then your indexes' retention should be based on size rather than time. Put your indexes in a volume and limit the size of the volume to the size of the disk minus 10-15%. As space grows tight, older buckets will be deleted to make room for new ones.
I would suggest you to read about archiving, this could be a better way to safely free some disk space, not losing permanently all data you have indexed before: https://docs.splunk.com/Documentation/Splunk/7.3.1/Indexer/Setaretirementandarchivingpolicy
Using a correct archiving and retirement policy can help you to remove or backup old indexed data, since you can choose to archive frozen buckets or to remove them. You just need to set when you want a bucket to turn to frozen.
I'm tempted to down-vote this answer. The splunk clean
command deletes the entire index, something the OP doesn't want.
I removed the splunk clean
command from my answer, thanks for the advice.