Home » RDBMS Server » Backup & Recovery » Implications Of A Full Monthly Backup And Recovery Windows of 7 Days (11.2.0.1, RHEL 7.1)
Implications Of A Full Monthly Backup And Recovery Windows of 7 Days [message #644851] Wed, 18 November 2015 22:28 Go to next message
juniordbanewbie
Messages: 176
Registered: April 2014
Senior Member
Dear all,

my supervisor suggested monthly FULL DB Backup with a RECOVERY WINDOWS OF 7 DAYS, the first thing that come to my mind is the implication of DB Storage.

from https://docs.oracle.com/cd/E11882_01/backup.112/e10642/rcmcncpt.htm#BRADV89502

The FULL DB is taken fornightly, i.e biweekly,

Based on the current time of 30 JAN and point OF recovery of 23 JAN, a FULL BACKUP done at 15 Jan is required=> which means that a backup storage that can last two weeks of backup is required.

Based on my situation, of 30 days full backup, storage space is even more right? It needs to have a backup space that can store up to 30 days of backup since in my case I still need to keep my Dec 31 backup full backup.

To conclude if retention policy is based on recovery window of X days and a full backup is done every Y days, then the backup space required is X days of backup even though the Y days is < X days. I would say that it's a grand mismatch between recovery window and full backup frequency

many many thanks!
Re: Implications Of A Full Monthly Backup And Recovery Windows of 7 Days [message #644857 is a reply to message #644851] Thu, 19 November 2015 01:44 Go to previous messageGo to next message
John Watson
Messages: 7212
Registered: January 2010
Location: Global Village
Senior Member
I think you are confusing backups with archive logfiles.
Re: Implications Of A Full Monthly Backup And Recovery Windows of 7 Days [message #644890 is a reply to message #644851] Thu, 19 November 2015 06:41 Go to previous messageGo to next message
EdStevens
Messages: 887
Registered: September 2013
Senior Member
ALL recovery begins with a restore of the most recent full backup. So your most recent full backup will never be obsolete, no matter how old it is, and no matter what your retention policy is. And depending on the nature of your incremental backups, some of them (as well as some archivelogs) may not be considered obsolete, regardless of their age vs. your retention policy.

If your business determines that a seven day recovery window is sufficient, then you should be taking a full (incremental level 0) backup at least every 7 days.

Did you ask your supervisor what his reasoning was in specify a recovery window of 7 days with a monthly full backup? When he says (or you say) "full" backup, do you mean that in the strict definition of an rman "full backup", which has different implications than an rman "incremental level 0" backup?

You seem concerned about disk space. What's more expensive, sufficient disk to hold the backups required to protect the business, or the loss of the database or some days worth of transactions?
Re: Implications Of A Full Monthly Backup And Recovery Windows of 7 Days [message #644923 is a reply to message #644890] Thu, 19 November 2015 19:53 Go to previous message
juniordbanewbie
Messages: 176
Registered: April 2014
Senior Member
Did you ask your supervisor what his reasoning was in specify a recovery window of 7 days with a monthly full backup? =>most likely time taken to do full backup. Unfortunately, it also implicitly means that the backup space may store up to 30 days of backup including archivelog backup causing space constraint.=>customer is on budget.

When he says (or you say) "full" backup, do you mean that in the strict definition of an rman "full backup" =>we mean level 0 backup because it is more flexible. If more space available then u can immediately do a level 1 backup

which has different implications than an rman "incremental level 0" backup=> what implication does it have beside the one I mention previously?

What's more expensive, sufficient disk to hold the backups required to protect the business, or the loss of the database or some days worth of transactions? Of course I will say loss of the database or some days worth of transactions

If your business determines that a seven day recovery window is sufficient, then you should be taking a full (incremental level 0) backup at least every 7 days.
=>I will highlight this to my supervisor since there's a grand mismatch between backup frequency and retention policy
=>that's the whole purpose of my post to confirm that my understanding is correct.

thanks a lot!
Previous Topic: How Long Will A Full Rman Compressed Backup Take Given The Following Specs
Next Topic: The Data Unloader DUL utility
Goto Forum:
  


Current Time: Tue Jan 16 16:20:48 CST 2018

Total time taken to generate the page: 0.02473 seconds