Re: Backup on standby database

From: Powell, Mark <mark.powell2_at_dxc.com>
Date: Thu, 13 May 2021 17:18:39 +0000
Message-ID: <BN6PR01MB25476F59BC2FA9BCF9D6698FCE519_at_BN6PR01MB2547.prod.exchangelabs.com>

"You MUST restore the last full backup and all incremental backups taken after the last full. It is much simpler to restore only the last full backup and apply the logs."

Why is it simpler? You just issue recover database and rman takes care of the rest. it is not like you must manually figure out which incremental backups and archive logs you need to apply.

While I would prefer running level 0 backups daily where possible and may or may not use level 1 backups with them the only real cost of level 1 backups is the extra file space consumed by the level 1 backup that would not be consumed if you only ran archive logs backups to go along with your level 0 or full. On systems with high update to the same rows use of level 1 backups can save a log of recovery time and time to recover is important.

Mark Powell
Database Administration
(313) 592-5148

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From: oracle-l-bounce_at_freelists.org <oracle-l-bounce_at_freelists.org> on behalf of Mladen Gogala <gogala.mladen_at_gmail.com> Sent: Thursday, May 13, 2021 11:01 AM
To: Jared Still <jkstill_at_gmail.com>
Cc: Oracle-L Freelists <oracle-l_at_freelists.org> Subject: Re: Backup on standby database

Well, it is not possible to recover DB from an incremental backup alone. You MUST restore the last full backup and all incremental backups taken after the last full. It is much simpler to restore only the last full backup and apply the logs. That is possible if you have daily full backups w/o any incremental backups. The problem with such strategy is storage, not the duration of the full backup which takes longer than the incremental. That doesn't matter since the standby is not open and is not doing anything for the end users. Nobody will suffer because you're running backup from standby. The storage problem can be resolved by deduplication. If the OP's backup software supports deduplication, and pretty much every backup suite does support it, his subsequent full backups will take as much space as an incremental.

On 5/13/21 10:01 AM, Jared Still wrote:
Hi Mladen,

Please explain:

Also, if you plan on running incremental backups, which I don't consider a good idea,

Jared Still
Certifiable Oracle DBA and Part Time Perl Evangelist Principal Consultant at Pythian
Oracle ACE Alumni
Pythian Blog http://www.pythian.com/blog/author/still/<https://clicktime.symantec.com/a/1/mJVSISzEHH_JAKz4tadrbRlYlYaxeNAK2II35gDcTY8=?d=hLvgTrsk498zgqlutYWbrJKoENsE3eej5Vig62q94j0BZZlIBO_Yv1wM18JrdYtAcOouO6FH1gJrR8CtfGdV-FTfSpUzhC1jktpFxVfDUFDTe0w3-jWFl8rrmDXfFeBSqOy-SWgIt6Ldh4A6e-LM21aRfC2IEhAdR6e_mcmhVRvbtZVkGOCX2lCIemFLfDLzolwBiLi2jJ45vruLkGuh9j30Z3QlgZmCJU-E758oVP4qVAso9MAVW-au9bywxEkdzslpbOneuMflAsGAVFDrNzpmkbx1RCEkfAyNDPD2lUJKRsEUAQaY241Mo69DZS-05Qt4YWFjE4SmAqD_9M5NA908wX9qTXy8_CCaZkUcp1rL5g9syMU6G9eM3r88iX4G9l0_BsLCz6r77YAJrlNEmQ8fmzL95XHPic5upOGaxWQf_m-KKH-TFAhzbVJdpQgc_8Z_&u=http%3A%2F%2Fwww.pythian.com%2Fblog%2Fauthor%2Fstill%2F> Github: https://github.com/jkstill<https://clicktime.symantec.com/a/1/xVPUmQWc5I54MyvyOLlGVR4xucrp39n40JumOJDHzhI=?d=hLvgTrsk498zgqlutYWbrJKoENsE3eej5Vig62q94j0BZZlIBO_Yv1wM18JrdYtAcOouO6FH1gJrR8CtfGdV-FTfSpUzhC1jktpFxVfDUFDTe0w3-jWFl8rrmDXfFeBSqOy-SWgIt6Ldh4A6e-LM21aRfC2IEhAdR6e_mcmhVRvbtZVkGOCX2lCIemFLfDLzolwBiLi2jJ45vruLkGuh9j30Z3QlgZmCJU-E758oVP4qVAso9MAVW-au9bywxEkdzslpbOneuMflAsGAVFDrNzpmkbx1RCEkfAyNDPD2lUJKRsEUAQaY241Mo69DZS-05Qt4YWFjE4SmAqD_9M5NA908wX9qTXy8_CCaZkUcp1rL5g9syMU6G9eM3r88iX4G9l0_BsLCz6r77YAJrlNEmQ8fmzL95XHPic5upOGaxWQf_m-KKH-TFAhzbVJdpQgc_8Z_&u=https%3A%2F%2Fgithub.com%2Fjkstill>

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Mladen Gogala
Database Consultant
Tel: (347) 321-1217
https://dbwhisperer.wordpress.com<https://clicktime.symantec.com/a/1/z3OB4l0tHKYEqyX9dB5pwAtjADgiQgdf1usx1snB77o=?d=hLvgTrsk498zgqlutYWbrJKoENsE3eej5Vig62q94j0BZZlIBO_Yv1wM18JrdYtAcOouO6FH1gJrR8CtfGdV-FTfSpUzhC1jktpFxVfDUFDTe0w3-jWFl8rrmDXfFeBSqOy-SWgIt6Ldh4A6e-LM21aRfC2IEhAdR6e_mcmhVRvbtZVkGOCX2lCIemFLfDLzolwBiLi2jJ45vruLkGuh9j30Z3QlgZmCJU-E758oVP4qVAso9MAVW-au9bywxEkdzslpbOneuMflAsGAVFDrNzpmkbx1RCEkfAyNDPD2lUJKRsEUAQaY241Mo69DZS-05Qt4YWFjE4SmAqD_9M5NA908wX9qTXy8_CCaZkUcp1rL5g9syMU6G9eM3r88iX4G9l0_BsLCz6r77YAJrlNEmQ8fmzL95XHPic5upOGaxWQf_m-KKH-TFAhzbVJdpQgc_8Z_&u=https%3A%2F%2Fdbwhisperer.wordpress.com>

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http://www.freelists.org/webpage/oracle-l Received on Thu May 13 2021 - 19:18:39 CEST