Fallback Strategy: Partial Offline Backup

Oh, I think it took us years to get rid of recommendations in MOS notes saying before this or that change you must take an offline backup. These recommendations dated back to times where not almost everybody was using RMAN for online backups. But the times have changed. Still, there are situations where the “Offline Backup” word can be mentioned. And in this blog post I will describe a Fallback Strategy: Partial Offline Backup. Usage Scenario This method will only protect you against failure during an upgrade. First of all, Offline Backup sounds really brutal and old-fashioned. But this method…

Guaranteed Restore Points and COMPATIBLE parameter

A while ago I blogged about Fallback Strategy: Flashback Database to Guaranteed Restore Points. I included a recommendation that you must not change the COMPATIBLE setting. But I should have been a bit more clear and precise about Guaranteed Restore Points and COMPATIBLE parameter settings. Guaranteed Restore Points and COMPATIBLE parameter First of all, you can’t use FLASHBACK DATABASE to a Guaranteed Restore Point when you changed to COMPATIBLE parameter. This was a common pitfall in older Oracle releases. But with Oracle Database 12.2.0.1 we add a tiny change which prevents you from accidentally changing COMPATIBLE while your fallback relies…

Fallback Strategies with Full Transportable Export/Import

I received an interesting question about how to implement Fallback Strategies with Full Transportable Export/Import several times within the past weeks. So it may be a good idea to showcase some possible scenarios. Full Transportable Export/Import is an Oracle 12c feature which allows you to do a transportable tablespace migration but Data Pump will take away all the manual steps with only one command. You may need to have markers to revert to in order to avoid restarting the entire operation from scratch again. And there are some special behaviors to know about, at first with Full Transportable Export/Import but…

Oracle 12.2 underscores appear in SPFILE – be aware when you flashback

I did blog in the past weeks about Fallback Strategies with Flashback Database. But two of my reference customers came across an interesting issue when they tried to fallback: Oracle 12.2 underscores appear in the SPFILE – magically – and prevent the fallback using the existing SPFILE. Oracle 12.2 underscores appear in SPFILE – be aware when you flashback In one case it happened during a test, in the other case it happened during a live fallback after the Data Guard Broker has interfered with the upgrade causing real trouble. In both cases the SPFILE sits in ASM. Both customers…

Fallback Strategy: Flashback Pluggable Database

Since Oracle Database 12.2 an important feature works now for pluggable databases as a Fallback Strategy: Flashback Pluggable Database in Oracle 12.2. This was missing in Oracle Database 12.1. Actually I missed this feature a lot as I use “Flashback” almost everyday. And you could only rewind the entire deployment with a FLASHBACK DATABASE command. Fallback Strategy: Flashback Pluggable Database Actually having the possibility to flashback a pluggable database without effecting the other PDBs is really important. Did you ever want to try out what happens if you TRUNCATE TABLE SYS.PROPS$? Give it a try – but set a Guaranteed…

Fallback Strategy: Flashback to Guaranteed Restore Points

You can attempt an Oracle database upgrade without having a fallback strategy. Of course you can. If you are brave enough. But I would recommend you this Fallback Strategy: Flashback to Guaranteed Restore Points. It is simple, easy, fast. And yes, it is an Enterprise Edition only feature. I have blogged about it in the past already but I realized it need some refresh. Fallback Strategy: Flashback to Guaranteed Restore Points One of the fastest way to revert from a big change (i.e. a database upgrade, an application upgrade, etc) is Flashback Database to a previously created Guaranted Restore Point….

Guaranteed Restore Points as Fallback Method

Thanks to the great audience yesterday in the Upgrade & Migration Workshop in Utrecht. That was really fun and I was amazed by our new facilities (and the  “wellness” lights surrounding the plenum room’s walls). And another reason why I like to do these workshops is that often I learn new things from you 🙂 So credits here to Rick van  Ek who has highlighted the following topic to me. Yesterday (and in some previous workshops) I did mention during the discussion about Fallback Strategies that you’ll have to switch on Flashback Database beforehand to create a guaranteed restore point…

Upgrade Fallback: Offline Backup??

When me an Roy talk about Fallback Scenarios in our Upgrade Workshop we cover first issues happening during the upgrade and second issues happening a few days (hours, weeks) after the upgrade. One of the fallback options for issues encountered during the upgrade is to take an offline backup. Ok, not a complete offline backup of your 24TB database. Take all data tablespaces into read-only mode, then shutdown the database. Take a backup of all datafiles for SYSTEM, SYSAUX and UNDO plus the controlfiles plus the redologs. TEMP files are not a requirement as you could also ALTER TABLESPACE TEMP…