Recovering a standby over the network in 12c

Martins Blog

Another one of the cool but underrated features in 12c is the possibility to recover a physical standby over the network with one line in RMAN.

Why do you need to perform this activity? Assume someone really clever created a segment “nologging” and the database was not in force logging mode. This operation cannot be replicated by redo apply on the standby, and you are bound to have a problem. Or, in my case, I had the standby shut down in my lab environment (intentionally) and created a few PDBs on my primary. For some reason I lost an archived redo log. This would of course not happen in a production environment, but my lab VM is limited when it comes to space and I may have moved my backup to a USB disk that I didn’t bring along.

So a long story short: you either recreate the standby-which is…

View original post 653 more words


Recreate the standby controlfile when using ASM

Martins Blog

This is in reply to some work I was supposed to carry out over the weekend on a DR database. It could have been really simple, but it turned out it wasn’t. As part of a major migration I moved a 2TB database from OCFS to ASM, which worked really nicely with a Data Guard switchover operation. Trouble now was that the standby databases still references online redo log files on the file system rather than ASM. I wanted to get rid of these annoying messages by updating the control file which was already rectified on the primary.

Under normal (non ASM) circumstances that doesn’t cause any trouble, but since ASM has the naming convention “+DISGROUPNAME/db_unique_name” the standby controlfile isn’t that easy to replace. Well actually it is but I needed some more careful thinking.

The steps are quite simple:

  • Create a standby controlfile on the primary: alter database create…

View original post 1,575 more words

4 out of 5 dentists recommend this site