Correct, backup log with truncate_only does not work in 2008 and above, and bloody good riddance too. That was far too badly abused by people that didn't actually know what it did.
The replacement is to set the DB into simple recovery model.
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability
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