Hi,
So there is no supported way to close /delete old alarms out of the SQL DB.
You can deactivate NAS then drop the NAS_* tables in the sql db and then activate nas.
This will clear out old alarms in the SQL DB. However if they are still present in NAS they will be re-synced to the database.
If you would like to get rid of all current alarms you can deactivate NAS
go to the nas folder on the primary and delete the *.db file
then drop the nas_* tables from the back end SQL server and then activate nas.
This will clear all current alarms in the system.
To trouble shoot snmptd you will need to increase the loglevel to 5 and logsize to 75000 then review the logs when the issue is seen again.
hope this helps.