Bugs With Backup Compression And TDE

Parikshit Savjani provides recommendations on combining backup compression with Transparent Data Encryption:

In past months, we discovered some edge scenarios related to backup compression for TDE databases causing backups or restores to fail, hence our recommendations have been

  • Avoid using striped backups with TDE and backup compression.

  • If your database has virtual log files (VLFs) larger than 4GB then do not use backup compression with TDE for your log backups. If you don’t know what a VLF is, start here.

  • Avoid using WITH INIT for now when working with TDE and backup compression. Instead, use WITH FORMAT.

  • Avoid using backup checksum with TDE and backup compression

Brent Ozar explains the risk:

When you install a new version of SQL Server, you get new features – and sometimes, you’re not told about them. For example, when 2016’s TDE compression came out, nobody told you, “If you back up across multiple files, your backups might suddenly be compressed.” You didn’t know that you had a new thing to test – after all, I don’t know a lot of DBAs who have the time to test that the new version of SQL Server successfully performs restores. They restore their production databases into the new version, test a few things, and declare victory – but testing restores FROM the new version’s backups isn’t usually on that list.

Keep up to date on those patches.

Related Posts

Access Violation Error In SQL Server 2016 SP2 CU4

Lonny Niederstadt tracked down an ugly bug in SQL Server 2016 SP2 CU4: When I started investigating, the error was known only as an access violation, preventing some operations related to data cleansing or fact table versioning. It occurred deep within a series of stored procedures.  The execution environment included cross-database DELETE statements, cross-database synonyms, […]

Read More

When Differential Backups Grow Larger Than Fulls

Kenneth Fisher notes that differential backups can end up being larger than full backups of the same database: The thing about DBA Myths is that they are generally widespread and widely believed. At least I believed this one until I posted What’s a differential Backup?and Randolph West (b/t) pointed out that my belief that differential backups […]

Read More

Categories

September 2017
MTWTFSS
« Aug Oct »
 123
45678910
11121314151617
18192021222324
252627282930