RMAN backup retention time

[symon_braunbaer]

Dear experts,

we want to switch to BRBACKUP backups using RMAN. The backups will be saved on disk.

How can I please set the retention of the backups, so that backups (and archivelogs), let's say

older than 30 days will be automatically purged ?

Using normal BRBACKUP, I have managed this by setting cleanup_disk_backup = 30 and

cleanup_disk_archive = 30 and scheduling the Cleanup Logs job in DB13.

Now after switching to RMAN, old backups are not being purged.

I know that in RMAN it is possible to configure a recovery window (of let's say 30 days) and all the

backups, which are older, are being declared as expired. But even after that it is necessary to schedule

a "delete obsolete" job in oracle.

So, is that the correct way to go, or it is possible to make it with the Cleanup Logs job ? Or

using some other BRTOOLS trick ?

Many thanks!

[stefan_koehler]

Hi Symon,

>> I know that in RMAN it is possible to configure a recovery window (of let's say 30 days) and all the backups, which are older, are being declared as expired. But even after that it is necessary to schedule a "delete obsolete" job in oracle.

No, it is not in case of FRA. (Obsolete) Backups are automatically purged in FRA, if space is needed.

>> So maybe there is really no such BRTOOLS feature and it has to be done directly in RMAN ?

Parameter "rman_keep" is for keeping the meta information in the control file (longer than init parameter control_file_record_keep_time) - see description ("<days>: retention period in days of an RMAN backup in the control file"). Otherwise the backup meta information may be overwritten / deleted, even if the physical backup file is still available - in consequence you would need to re-register it manually.

BR*Tools (for backup/restore/recovery) are good for 0815 procedures and should be used by SAP admins with less database knowledge, but if you got an Oracle DBA team with RMAN knowledge and special needs - go for native RMAN. (especially with a direct Oracle support contract)

Regards

Stefan

[symon_braunbaer]

Dear Stefan,

many thanks for your answer!

We are not making backups to the FRA (Flash Recovery Area), but to an EMC DataDomain device, via a special EMC DD library for RMAN and Solaris.

We have a support contract with Oracle (or at least I think so!), but it has been decided to stick to

BRTOOLS and I should be presented with VERY strong arguments against BRTOOLS in order to

give them up...

So please anyone let me know if it is possible to set the retention time and if yes, then how??

Many thanks!

[stefan_koehler]

Hi Symon,

this is an important detail as you are using a 3rd party MML (if i understand you right) and you do not take classic backup to disk.

>> So please anyone let me know if it is possible to set the retention time and if yes, then how??

It is getting even more complex in case of 3rd party MMLs as you need to know which is the driving retention source. For example the retention policy of RMAN is used with IBM TDPO and you need to delete obsolete backups via RMAN, on the other hand the leading retention with Symantec NetBackup is NetBackup itself and you need to run crosschecks via RMAN to keep the RMAN repository in sync (the backups are deleted by the NetBackup itself).

I don't know the EMC DataDomain library, but you can easily find this out by running some simple tests on your own. However in every case you need to delete obsolete or crosscheck the backups.

By the way there is a "hidden" functionality in BR*Tools (command line option "-RCC" in combination with parameters cleanup_disk_archive and cleanup_disk_backup) for cleaning up the RMAN repository for disk backups (crosscheck + delete expired), but if this is valid in your case depends on the MML implementation.

Regards

Stefan

[symon_braunbaer]

Hi Stefan and many thanks for your answer!

In the company there are many non-SAP databases and our DB colleagues have more

experience with that, as they have been using it for quite some time and we are going

to implement it now for SAP...

Yes, they are doing crosscheck and delete obsolete, they told me that they have setup

a simple job in the oracle DBMS scheduler. We can do the same for our SAP systems.

Thanks for pointing out the -RCC command line option. Do you think that there is some

documentation for it somewhere, or all that we know is just "-RCC" ?

Many thanks in advance!

[stefan_koehler]

Hi Symon,

the "-RCC" command line option was an enhancement request from me some time ago as the BR*Tools create backup control files, but they do not clean up the RMAN repository after deleting the files in file system by default (by cleanup run). In consequence this lead to issues with Oracle Data Guard.

However if you are just doing a simple crosscheck and delete expired (not obsolete) by a disk channel with EMC DataDomain - then you don't need any additional job for that as this is implemented into BR*Tools with option "-RCC". If you need to allocate some other or special channel for your RMAN maintenance with EMC DataDomain - then you need an additional job.

Regards

Stefan

P.S.: You can observe the exact RMAN behavior / commands by enabling BR_TRACE (15).

[fidel_vales]

Hi,

I have not used that feature.

Perhaps the parameter rman_keep is what you are looking for:

rman_keep - SAP Database Guide: Oracle - SAP Library

let us know if it works

[symon_braunbaer]

Dear Fidel,

I found the following sentence in the link you have sent me:

"It should only be used for special backups (monthly or yearly) that are not part of the standard retention strategy."

So maybe there is really no such BRTOOLS feature and it has to be done directly in RMAN ?

Thank you!