How do you Audit Login Failures? Solutions? How do you Audit Login Failures? Solutions?
For SQL Server, Brian Kelly did a great write up at MSSQLTips.com. You can find it here: https://www.mssqltips.com/sqlservertip/1735/auditing-failed-logins-in-sql-server/

You can enable login auditing (and specify the level of logging) on the Server Properties screen under 'Security.'

To view the logs, execute 'EXEC SP_ReadErrorLog.' There are some parameters that can be added to filter, and look at older than current logs as well. You can also view events in Windows Event Log Viewer. The 'Source' will be the SQL Server instance name on the machine.