Is it possible to pull triggered alerts report for a duration of 12 months because i tried to do so but getting only triggered alerts for 1 month duration even when selected 12 months duration in time interval.
Mine only go back into November as well. Going forward you may want to schedule an end of the month report and save it off somewhere or log the alerts to an external file if you need to go back 12 months.
There a table called AlertHistory and AlertHistoryView. You can export these tables to CSV. You may also use the SQL query below to show you the oldest alerts you can put into a report.
SELECT * FROM [dbo].[AlertHistoryView]order by TimeStamp asc
Alerts are retained for the same amount of time as the events, which is 30 days by default but you can increase it over a year if you want.
https://support.solarwinds.com/SuccessCenter/s/article/Increase-Events-Retention?language=en_US
