Re: backup and online reso logs question

Oracle RMAN will also skip the online redo's in a hot backup. Not sure about the control file.
Your backup scenario is ok. You don't need the redologs in a hot backup. Why? To prevent you from accidently restoring them, loosing the latest transactions that are in the current redolog.

When you restore you minimal need:
a. all database files
b. all archives generated between "alter tablespace ... begin backup" and "alter tablespace ... end backup" including the latest one that was created with the "switch log" after " ... end backup" c. a controlfile with at least the proper structure information, that is: database file names and redolog file names. When it was made is not important as long as it was made after any file structure change (rename, resize etc..)
All these come from your backup.
From this you can recover your backup with: "recover database using backup controlfile" and "alter database open resetlogs".
Note that redologs are NOT required in this scenario, they are recreated (with the info from the control file) when you do ".. open resetlogs".

In real live you most likely have at least one good control file with the latest db status making recovery easier. And when you have all archives and redologs you can even recover until the latest committed transaction.

I sometimes compare archived log and redolog files with that slow running tape recorder in alarm centrals that record any conversation. You can reconstruct anything from that tape until the first second you lost. From than on it's unreliable.

michael.cooke <michael.cooke_at_tinyworld.co.uk> schreef in berichtnieuws 3ccb28e1_1_at_mk-nntp-1.news.uk.worldonline.com...
> Oracle 7.3.3 NT4sp6a (Veritas backup exec 8.6)
> currently generating a hot backup nightly
> using alter tablespace ...... begin backup for all tablespaces at the same
> time
> running NTbackup to xcopy all datafiles, controlfile, online redolog files
> etc to another PC. alter tablespace ...... end backup, logswitch backup
> control to trace etc the backup copy is then copied to tape along with the
> archived redo logs.
> I then load the content of the tape to a sandalone test server open the
> database after using the recover database option and am able to use it for
> test purposes in the knowledge that I have a fully recoverable backup.
> I am going over to a new server soon and will be using veritas backup exec
> 8.6 with the oracle agent. I have tested the backup process using this
> option and notice it does not backup the online redo logs or controlfile
> (creates a copies a backup). To be able to carryout a full recovery (if
you
> lose the server completely) you need the online logfiles as well as all
the
> others else you cannot open the db. does anyone out there use veritas to
> create hot backups and have they had any problems recovering a full dbase
as
> I will still need to be able to restory onto my test server? how did you
> get around the online redologs not being backed up?
>
> sorry its a bit like war & peace and hope someone has the patients to read
> an answer it.
>
> regds
> Mick
>
>
Received on Sat Apr 27 2002 - 18:08:34 CDT