Shrinking Log file in SQL Server 2008

Procedure of shrinking DB log file (transaction log file). In SQL Server Management Studio

Right click on a DB, Properties -> Options-> Recovery model -> change from 'Full' to 'Simple' -> OK
Right click on a DB -> Tasks -> Shrink -> Files ->  File type -> Log -> OK

The shrinking procedure should not take more than 3 s. It is not possible to change DB Recovery mode this way if a mirroring is setup. Now, some rules of shrinking and maintaining log file.

• By default Recovery model is set to FULL
• If you store in a DB crucial/important information, then recovery model should be set to FULL
• If recovery model is set to FULL, it means that there should be a backup in place, a backup that also includes a transaction log file
• When a backup for a transaction log file runs, the transaction log file is shrink. The truncation occurs after a Checkpoint process
• So if your transaction log is big, like 7 GB, it means that you:
  • Don't have a backup that includes transaction log fie. And it means that you don't need FULL recovery mode
  • Your backup is not working
  • You have a big and heavily used database