While I'm doing my own investigation, does anyone know why a database in
SIMPLE recovery model has
LOG_BACKUP for the
SQL Server 2012 SP1. Database created just a few weeks ago. No replication, no mirroring, no log shipping, and never has had any of those.
We did backup the database and restore to another instance, it shows
log_reuse_wait on the other instance. But I don't think restore to another instance is a good way to reproduce the problem as restore operation rolls-forward/rolls back transactions.