Again, well put, a good omission to mention, and in accordance with “Never
trust your career to a single piece of spinning rust or ribbon rust.” Thanks!
As for the path about quick business continuation of very massive sets, meeting
such a requirement with backups rather than switch-over targets of some sort
implicitly requires that the full backup itself, any incrementals, and at least
one copy of the archived redo logs is on fast media that in the case of the
full backup can merely be pointed to in place of the primary files as opposed
to being copied at all. I also recommend that the online logs and last good
control file be preserved somewhere fast as the first step of recovery,
preserving your ability to try again should they be modified during a recovery
that fails for any reason.
mwf
From: kathryn axelrod [mailto:kat.axe@xxxxxxxxx]
Sent: Sunday, November 22, 2015 8:30 PM
To: mwf@xxxxxxxx
Cc: sbecker6925@xxxxxxxxx; Brian.Zelli@xxxxxxxxxxxxxxx; oracle-l
Subject: diff between incremental and archive backups
There seem two paths on the topic.
Replying to the first one, I didn't see this mentioned, so apologize if it
was: i'd add the warning that, if the plan has only one copy of the logs backed
up and you lose just one of those many logs, you may lose a Lot of data. e.g.
you do a full on Sunday, Jan 1..lose one log on Monday, Jan 2 due to corruption
or other..and you decide you want to do a pitr on Saturday, January 7..you
can't. You'll be forced to go all the way back to right before the missing log.
On Friday, November 13, 2015, Mark W. Farnham <mwf@xxxxxxxx
<javascript:_e(%7B%7D,'cvml','mwf@xxxxxxxx');> > wrote:
Well put.
Consider also that if a given block is modified many times, then the size of
the deltas in the redo stream likely exceeds the size of the one current
version of the block that will need to be written to the incremental backup and
applied in the course of rolling forward from the full backup through any
incrementals.
Having the two possible recovery scenarios might allow you to minimize the
recovery time depending on the texture of updates to your database.
mwf
From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On
Behalf Of Sandra Becker
Sent: Friday, November 13, 2015 2:10 PM
To: Brian.Zelli@xxxxxxxxxxxxxxx
Cc: oracle-l (oracle-l@xxxxxxxxxxxxx)
Subject: Re: diff between incremental and archive backups
Depending on how many archivelogs your database writes in a week, that could be
a lot of logs to apply. Consider if you have the space to store them, or time
to restore them to disk, and the time to apply all the logs vs. doing
incremental backups and applying fewer logs. Just something to consider.
Sandy B.
On Fri, Nov 13, 2015 at 11:59 AM, Zelli, Brian <Brian.Zelli@xxxxxxxxxxxxxxx>
wrote:
So we were having a discussion about rman incremental backups. And the
question came up that if I do an rman full once a week and then rman back up of
the archive logs the rest of the week, that’s all I need to do a point in time
restore. I don’t have to do incremental backups. Is this an accurate
assumption?
Brian
This email message may contain legally privileged and/or confidential
information. If you are not the intended recipient(s), or the employee or agent
responsible for the delivery of this message to the intended recipient(s), you
are hereby notified that any disclosure, copying, distribution, or use of this
email message is prohibited. If you have received this message in error, please
notify the sender immediately by e-mail and delete this email message from your
computer. Thank you.
--
Sandy B.
