Seeing that the recovery model is set to simple and msdn states that the simple recovery model does not support point-in-time recovery - Does this mean that I won't be able to use my transaction log backups to restore the database in a disaster to an hour before it happened?
Even taking a transaction log backup is not supported for databases using the SIMPLE
recovery model. This is a restriction of the database engine based on how this recovery model works, and the recovery features it doesn't support, as you mentioned.
A transaction log backup maintenance plan task automatically skips databases in SIMPLE
recovery to avoid causing errors.
Which backup should be done first, the database backup or the transaction log backups? Articles that I'm busy reading say I should do the database backup first and then the transaction log backup else I will get maintenance plan errors, but I'm currently first backing up my transaction logs and then data databases and I'm not getting any errors.
For the reasons I mentioned above, it won't matter for databases using SIMPLE
recovery, as they will be skipped by the transaction log backup task.
For databases in the other two recovery models, a full backup must exist before you start taking transaction log backups (just the first time), or you will get an error -- this is probably what the articles refer to.
Point-in-time recovery ability is normally driven by business need -- in other words, you determine how critical the data is and how much you can afford to lose, then set the appropriate recovery model to meet those needs, and finally create a backup solution.
Even though SIMPLE
recovery does not support point-in-time recovery, if an hour of data loss is okay, perhaps a differential backup solution could work for you. (There are far too many variables that go into developing this kind of solution to give you a complete picture with what was provided in the question.)
This KB isn't directly related but the quote in it is:
MSKB2615182: Windows Server Backup May Fail Because of the SQL VSS Writer:
When Windows Server Backup attempts to backup a disk volume, a Volume Shadow Copy Snapshot is created for the volume. When the snapshot is created any VSS writer associated with the volume is called.
If there are SQL Server VSS writer backups being taken then you will see records in the MSDB.dbo.BackupMediaFamily
table in the physical_device_name
column. You might want to look into disabling the SQL Writer Service
.
TechNet: SQL Writer Service
Best Answer
The problem was that i was doing a classic backup using windows server utility (nothing to have with DB backup) for some folder . I was doing backup for only 1 folder in the root of the C:\ drive .
But somehow when this backup starts it freezes the I/O on each database, then it resumes the I/O of all databases and finally all DB are backed up .