Oracle: Relocate Fast-Recovery-Area (FRA)

As our database grows and grows, here especially in respect of backupsize and daily generated archive-logs, we may sometime get to a point when we have to relocate our FRA to another device with more free space. This could also be the case in a situation when we have run out of FRA-space because of an unexpected sudden massive increase of archived redologs. I just had the latter when some developers had run an upgrade of their application.

Luckily it is no big fuss to change the FRAs destination directory. It’s just a matter of changing the location with

alter system set db_recovery_file_dest='/usr4/oracle/fast_recovery_area' scope=both;

and increasing the FRAs size with

alter system set db_recovery_file_dest_size=100g scope=both;

To test the new settings we can initiate a redolog-archiving:

alter system switch logfile;
alter system checkpoint;

After this we should see a new subdirectory in the new FRA-Location with our DB’s SID as name and some subfolders in there containing our archived redolog.

Beware not to move the existing/old FRA-Files to the new location using OS-Commands, as the DB would not notice this and couldn’t keep track of that files. We can just let the files stay in the old FRA-Location until they age out and get deleted automatically by our DB. The absolute path to each file is recorded in the DB, so that the change of the db_recovery_file_dest is no problem for existing files. But keep in mind, that the overall size of files in the old db_recovery_file_dest adds up to the total size of our FRA. The FRA is a mere virtual concept that has no necessary 1:1 relationship to a physical directory on disc. So if we create a backup outside of our db_recovery_file_dest, this adds up too to our FRA-Size.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: