Beginning in Snort 2.9.2, if you are using an output method that is being depreciated in a future version of Snort, we are going to warn you on startup.
Examples of these depreciated output methods that you will be warned about are:
spo_database (Direct to database output method, or commonly referred to as the "database output method")
spo_aruba (Aruba output plugin)
spo_prelude (Prelude output plugin)
These output plugins will be totally removed in Snort version 2.9.3.
We are not depreciating "unified1" as an output method in 2.9.3, but we do have plans for it's EOL as well.
We suggest moving to unified2 as an output method, and also to barnyard2 (if you are still using the original barnyard)