What is a 'cold bucket' in Splunk?

In Splunk, a cold bucket refers to a storage area for data that is no longer actively written to. When data first arrives in Splunk, it goes through several stages of storage: it initially resides in hot buckets, transitions to warm buckets as it is indexed, and eventually moves to cold buckets as it ages and is accessed less frequently. This process helps to manage storage efficiency and performance, as cold buckets are typically stored on less expensive, slower storage compared to hot and warm buckets. Cold buckets still retain the data and are searchable, but they are utilized for historical data access rather than real-time analysis. This helps organizations optimize their data storage strategies while still enabling the retrieval of older data when needed.