RMAN archivelog backup

Yesterday I encountered a problem with a RMAN backup. There were no backups of archivelogs, only datafile backups and archivelogs. So I investigated the issue and found the following backup script:

backup database archivelog all delete input;
delete noprompt obsolete;

Looks good at the first glance but what it does is not what I wanted it to do. The “redundancy” is configured to be 1. So what happens is this, first the database is being backued up and right after it the archivelogs are being backed up to. But only those archivelogs that existed at the time the backup command started. No archivelogs that were created during the database backup are being backed up. So the archivelog backups become obsolete immediately and are deleted by the following “delete obsolete” command.
The thing is, the script should look like this:

backup database plus archivelog delete input;
delete noprompt obsolete;

Minor change with a major impact.

Let’s see what happens in both cases

Case 1

Check what sequences are in the online logs and generate some more:

[oracle@oel6u4 ~]$ sqlplus / as sysdba

SQL*Plus: Release 12.1.0.2.0 Production on Wed Sep 13 10:45:04 2017

Copyright (c) 1982, 2014, Oracle.  All rights reserved.


Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing opt                                                                ions

SYS@db12cb> select group#, sequence#, status from v$log;

    GROUP#  SEQUENCE# STATUS
---------- ---------- ---------------
         1         16 CURRENT
         2         14 ACTIVE
         3         15 ACTIVE

SYS@db12cb> alter system switch logfile;

System altered.

SYS@db12cb> alter system switch logfile;

System altered.

SYS@db12cb> alter system switch logfile;

System altered.

SYS@db12cb> alter system checkpoint;

System altered.

SYS@db12cb> select group#, sequence#, status from v$log;

    GROUP#  SEQUENCE# STATUS
---------- ---------- ---------------
         1         19 CURRENT
         2         17 INACTIVE
         3         18 INACTIVE

At that point we have archivelogs until sequnce 18. Now we start the RMAN backup:

[oracle@oel6u4 ~]$ rman target /

Recovery Manager: Release 12.1.0.2.0 - Production on Wed Sep 13 10:48:07 2017

Copyright (c) 1982, 2014, Oracle and/or its affiliates.  All rights reserved.

connected to target database: DB12C (DBID=1357631873)

RMAN> backup database archivelog all delete input;

Starting backup at 13.09.2017 10:48:16
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=276 device type=DISK
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00005 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_example_d3lq5h14_.dbf
input datafile file number=00001 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_system_d3lq3d22_.dbf
input datafile file number=00003 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_sysaux_d3lq4lpd_.dbf
input datafile file number=00002 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_marco_d3qvwcwt_.dbf
input datafile file number=00004 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_undotbs1_d3lq5ctw_.dbf
input datafile file number=00006 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_users_d3lq6w0q_.dbf
channel ORA_DISK_1: starting piece 1 at 13.09.2017 10:48:17
channel ORA_DISK_1: finished piece 1 at 13.09.2017 10:51:02
piece handle=/u01/app/oracle/fra/DB12CB/backupset/2017_09_13/o1_mf_nnndf_TAG20170913T104816_dvkw6kls_.bkp tag=TAG20170913T104816 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:02:45
channel ORA_DISK_1: starting archived log backup set
channel ORA_DISK_1: specifying archived log(s) in backup set
input archived log thread=1 sequence=14 RECID=43 STAMP=954585900
input archived log thread=1 sequence=15 RECID=44 STAMP=954585901
input archived log thread=1 sequence=16 RECID=46 STAMP=954585995
input archived log thread=1 sequence=17 RECID=48 STAMP=954585996
input archived log thread=1 sequence=18 RECID=50 STAMP=954585998
channel ORA_DISK_1: starting piece 1 at 13.09.2017 10:51:02
channel ORA_DISK_1: finished piece 1 at 13.09.2017 10:51:05
piece handle=/u01/app/oracle/fra/DB12CB/backupset/2017_09_13/o1_mf_annnn_TAG20170913T104816_dvkwcpnp_.bkp tag=TAG20170913T104816 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:03
channel ORA_DISK_1: deleting archived log(s)
archived log file name=/u01/app/oracle/fra/DB12CB/archivelog/2017_09_13/o1_mf_1_14_dvkw0cm1_.arc RECID=43 STAMP=954585900
archived log file name=/u01/app/oracle/fra/DB12CB/archivelog/2017_09_13/o1_mf_1_15_dvkw0f1w_.arc RECID=44 STAMP=954585901
archived log file name=/u01/app/oracle/fra/DB12CB/archivelog/2017_09_13/o1_mf_1_16_dvkw3c38_.arc RECID=46 STAMP=954585995
archived log file name=/u01/app/oracle/fra/DB12CB/archivelog/2017_09_13/o1_mf_1_17_dvkw3d1f_.arc RECID=48 STAMP=954585996
archived log file name=/u01/app/oracle/fra/DB12CB/archivelog/2017_09_13/o1_mf_1_18_dvkw3g00_.arc RECID=50 STAMP=954585998
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
including current control file in backup set
including current SPFILE in backup set
channel ORA_DISK_1: starting piece 1 at 13.09.2017 10:51:09
channel ORA_DISK_1: finished piece 1 at 13.09.2017 10:51:10
piece handle=/u01/app/oracle/fra/DB12CB/backupset/2017_09_13/o1_mf_ncsnf_TAG20170913T104816_dvkwcx24_.bkp tag=TAG20170913T104816 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
Finished backup at 13.09.2017 10:51:10

We see, that all archivelogs until and including sequence 18 are being backed up. No sign of sequence 19 or any sequence beyond that.

Case 2

Again, we check the sequences in the online logs. There is no change to what we had ad the beginning of Case-1-Backup. That’s why I create some more archivelogs.

[oracle@oel6u4 ~]$ sqlplus / as sysdba

SQL*Plus: Release 12.1.0.2.0 Production on Wed Sep 13 12:36:06 2017

Copyright (c) 1982, 2014, Oracle.  All rights reserved.


Connected to:
Oracle Database 12c Enterprise Edition Release 12.1.0.2.0 - 64bit Production
With the Partitioning, OLAP, Advanced Analytics and Real Application Testing options

SYS@db12cb> select group#, sequence#, status from v$log;

    GROUP#  SEQUENCE# STATUS
---------- ---------- ---------------
         1         19 CURRENT
         2         17 INACTIVE
         3         18 INACTIVE

SYS@db12cb> alter system switch logfile;

System altered.

SYS@db12cb> alter system switch logfile;

System altered.

SYS@db12cb> alter system checkpoint;

System altered.

SYS@db12cb> select group#, sequence#, status from v$log;

    GROUP#  SEQUENCE# STATUS
---------- ---------- ---------------
         1         19 INACTIVE
         2         20 INACTIVE
         3         21 CURRENT

Now we start the backup with the slightly modified command:

[oracle@oel6u4 ~]$ rman target /

Recovery Manager: Release 12.1.0.2.0 - Production on Wed Sep 13 12:36:41 2017

Copyright (c) 1982, 2014, Oracle and/or its affiliates.  All rights reserved.

connected to target database: DB12C (DBID=1357631873)

RMAN> backup database plus archivelog delete input;


Starting backup at 13.09.2017 12:36:49
current log archived
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=264 device type=DISK
channel ORA_DISK_1: starting archived log backup set
channel ORA_DISK_1: specifying archived log(s) in backup set
input archived log thread=1 sequence=19 RECID=52 STAMP=954592574
input archived log thread=1 sequence=20 RECID=54 STAMP=954592575
input archived log thread=1 sequence=21 RECID=56 STAMP=954592610
channel ORA_DISK_1: starting piece 1 at 13.09.2017 12:36:50
channel ORA_DISK_1: finished piece 1 at 13.09.2017 12:36:51
piece handle=/u01/app/oracle/fra/DB12CB/backupset/2017_09_13/o1_mf_annnn_TAG20170913T123650_dvl2l2o8_.bkp tag=TAG20170913T123650 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_1: deleting archived log(s)
archived log file name=/u01/app/oracle/fra/DB12CB/archivelog/2017_09_13/o1_mf_1_19_dvl2jx41_.arc RECID=52 STAMP=954592574
archived log file name=/u01/app/oracle/fra/DB12CB/archivelog/2017_09_13/o1_mf_1_20_dvl2jzhj_.arc RECID=54 STAMP=954592575
archived log file name=/u01/app/oracle/fra/DB12CB/archivelog/2017_09_13/o1_mf_1_21_dvl2l23m_.arc RECID=56 STAMP=954592610
Finished backup at 13.09.2017 12:36:51

Starting backup at 13.09.2017 12:36:51
using channel ORA_DISK_1
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
input datafile file number=00005 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_example_d3lq5h14_.dbf
input datafile file number=00001 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_system_d3lq3d22_.dbf
input datafile file number=00003 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_sysaux_d3lq4lpd_.dbf
input datafile file number=00002 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_marco_d3qvwcwt_.dbf
input datafile file number=00004 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_undotbs1_d3lq5ctw_.dbf
input datafile file number=00006 name=/u01/app/oracle/oradata/DB12CB/datafile/o1_mf_users_d3lq6w0q_.dbf
channel ORA_DISK_1: starting piece 1 at 13.09.2017 12:36:52
channel ORA_DISK_1: finished piece 1 at 13.09.2017 12:39:07
piece handle=/u01/app/oracle/fra/DB12CB/backupset/2017_09_13/o1_mf_nnndf_TAG20170913T123651_dvl2l435_.bkp tag=TAG20170913T123651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:02:15
channel ORA_DISK_1: starting full datafile backup set
channel ORA_DISK_1: specifying datafile(s) in backup set
including current control file in backup set
including current SPFILE in backup set
channel ORA_DISK_1: starting piece 1 at 13.09.2017 12:39:08
channel ORA_DISK_1: finished piece 1 at 13.09.2017 12:39:09
piece handle=/u01/app/oracle/fra/DB12CB/backupset/2017_09_13/o1_mf_ncsnf_TAG20170913T123651_dvl2pd9n_.bkp tag=TAG20170913T123651 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
Finished backup at 13.09.2017 12:39:09

Starting backup at 13.09.2017 12:39:09
current log archived
using channel ORA_DISK_1
channel ORA_DISK_1: starting archived log backup set
channel ORA_DISK_1: specifying archived log(s) in backup set
input archived log thread=1 sequence=22 RECID=58 STAMP=954592749
channel ORA_DISK_1: starting piece 1 at 13.09.2017 12:39:09
channel ORA_DISK_1: finished piece 1 at 13.09.2017 12:39:10
piece handle=/u01/app/oracle/fra/DB12CB/backupset/2017_09_13/o1_mf_annnn_TAG20170913T123909_dvl2pfxh_.bkp tag=TAG20170913T123909 comment=NONE
channel ORA_DISK_1: backup set complete, elapsed time: 00:00:01
channel ORA_DISK_1: deleting archived log(s)
archived log file name=/u01/app/oracle/fra/DB12CB/archivelog/2017_09_13/o1_mf_1_22_dvl2pflz_.arc RECID=58 STAMP=954592749
Finished backup at 13.09.2017 12:39:10

Looks different now. We have a logswitch at the very beginning of the backup. Then all the archivelogs that exists at that point are being backed up. Then there is the database backup. And finally another logswitch is done and all the logs that were created during the database backup are being backed up too.
That is, what I really want.

Conclusion

The effect of the “plus archivelog” syntax is completely different from the combined “backup” command for different file types. So be very careful which option you use and most important: check your backup strategy by doing test restores on a regular basis.

Advertisements

RMAN delete obsolete but keep archivelogs

When doing RMAN backups we typically have one strategy and one policy. But the deletion policy always considers not only backups and copies but also archivelogs. In some cases one might want to keep archivelogs for a longer period of time, for instance if you are running a non-Dataguard Standby database using DBVisit. Let’s say we want to keep two generations of backups, we would do the following:

RMAN> CONFIGURE RETENTION POLICY TO REDUNDANCY 2;

new RMAN configuration parameters:
CONFIGURE RETENTION POLICY TO REDUNDANCY 2;
new RMAN configuration parameters are successfully stored

Now let’s see what backups we have:

RMAN> list backup of database summary;


List of Backups
===============
Key     TY LV S Device Type Completion Time     #Pieces #Copies Compressed Tag
------- -- -- - ----------- ------------------- ------- ------- ---------- ---
23      B  F  A DISK        22.12.2016 09:19:14 1       1       NO         TAG20161222T091750
27      B  F  A DISK        22.12.2016 10:02:33 1       1       NO         TAG20161222T100145
28      B  F  A DISK        22.12.2016 10:02:57 1       1       NO         TAG20161222T100145
29      B  F  A DISK        22.12.2016 10:03:22 1       1       NO         TAG20161222T100145
33      B  F  A DISK        22.12.2016 10:17:14 1       1       NO         TAG20161222T101632
34      B  F  A DISK        22.12.2016 10:17:32 1       1       NO         TAG20161222T101632
35      B  F  A DISK        22.12.2016 10:18:00 1       1       NO         TAG20161222T101632


RMAN> list backup of archivelog all summary;


List of Backups
===============
Key     TY LV S Device Type Completion Time     #Pieces #Copies Compressed Tag
------- -- -- - ----------- ------------------- ------- ------- ---------- ---
24      B  A  A DISK        22.12.2016 09:19:30 1       1       NO         TAG20161222T091930
26      B  A  A DISK        22.12.2016 10:01:34 1       1       NO         TAG20161222T100127
30      B  A  A DISK        22.12.2016 10:03:35 1       1       NO         TAG20161222T100335
32      B  A  A DISK        22.12.2016 10:16:24 1       1       NO         TAG20161222T101615
36      B  A  A DISK        22.12.2016 10:18:16 1       1       NO         TAG20161222T101815

So we have two database backups and corresponding backups of archivelogs. And what archivelogs are still on disk?

RMAN> list archivelog all;

List of Archived Log Copies for database with db_unique_name OLTP
=====================================================================

Key     Thrd Seq     S Low Time
------- ---- ------- - -------------------
46      1    15      A 21.12.2016 12:56:40
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_15_d5q709b5_.arc

41      1    16      A 22.12.2016 09:17:31
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_16_d5q709x1_.arc

43      1    17      A 22.12.2016 09:19:29
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_17_d5q709oq_.arc

35      1    18      A 22.12.2016 10:01:26
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_18_d5q5q65p_.arc

36      1    19      A 22.12.2016 10:03:33
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_19_d5q6gtmj_.arc

38      1    20      A 22.12.2016 10:16:10
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_20_d5q6lm3q_.arc

45      2    11      A 21.12.2016 12:56:30
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_11_d5q709gs_.arc

42      2    12      A 22.12.2016 09:17:20
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_12_d5q709xo_.arc

44      2    13      A 22.12.2016 09:19:14
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_13_d5q709ln_.arc

40      2    14      A 22.12.2016 10:01:12
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_14_d5q709pq_.arc

37      2    15      A 22.12.2016 10:03:18
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_15_d5q6gg9k_.arc

39      2    16      A 22.12.2016 10:15:58
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_16_d5q6l6jm_.arc

That’s all archivelogs that would be needed for recovery of the older database backup. Now let’s see what is obsolete:

RMAN> report obsolete;

RMAN retention policy will be applied to the command
RMAN retention policy is set to redundancy 2
Report of obsolete backups and copies
Type                 Key    Completion Time    Filename/Handle
-------------------- ------ ------------------ --------------------
Backup Set           23     22.12.2016 09:19:16
  Backup Piece       23     22.12.2016 09:19:16 /u01/app/oracle/fra/OLTP/43C6AA13C2390666E0538D24100A09EF/backupset/2016_12_22/o1_mf_nnndf_TAG20161222T091750_d5q33orv_.bkp
Backup Set           24     22.12.2016 09:19:30
  Backup Piece       24     22.12.2016 09:19:30 /u01/app/oracle/fra/OLTP/backupset/2016_12_22/o1_mf_annnn_TAG20161222T091930_d5q34ljw_.bkp
Backup Set           25     22.12.2016 09:19:34
  Backup Piece       25     22.12.2016 09:19:34 /u01/app/oracle/fra/OLTP/autobackup/2016_12_22/o1_mf_s_931252772_d5q34ol5_.bkp
Backup Set           26     22.12.2016 10:01:36
  Backup Piece       26     22.12.2016 10:01:36 /u01/app/oracle/fra/OLTP/backupset/2016_12_22/o1_mf_annnn_TAG20161222T100127_d5q5m88s_.bkp
Archive Log          43     22.12.2016 10:25:30 /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_17_d5q709oq_.arc
Archive Log          41     22.12.2016 10:25:30 /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_16_d5q709x1_.arc
Archive Log          42     22.12.2016 10:25:30 /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_12_d5q709xo_.arc
Archive Log          44     22.12.2016 10:25:31 /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_13_d5q709ln_.arc
Archive Log          45     22.12.2016 10:25:35 /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_11_d5q709gs_.arc
Archive Log          46     22.12.2016 10:25:37 /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_15_d5q709b5_.arc

The oldest backup is obsolete which is fine since we already have three full backups. Also all the archivelogs are obsolete since they were already backuped up and can be restored from those backups in case of emergency. But what can we do if we want to keep the archivelogs on disk as long as possible? A “delete obsolete” would remove them along with the outdated database backup.
Let’s try to keep them using “change”:

RMAN> change archivelog all keep until time 'sysdate+3';

released channel: ORA_DISK_1
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=279 instance=oltp_1 device type=DISK
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of KEEP command at 12/22/2016 10:29:34
RMAN-06529: CHANGE ... KEEP not supported for ARCHIVELOG

So that is not an option. Maybe changing them to “unavailable” might do the job?

RMAN> change archivelog all unavailable;

RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of unavailable command on ORA_DISK_1 channel at 12/22/2016 10:30:43
ORA-19813: cannot have unavailable file /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_15_d5q709b5_.arc in DB_RECOVERY_FILE_DEST

It is not possible to mark archivelog files in FRA as unavailable. There must be another way to excempt the archivelogs from the retention policy. The policy applies to all files known to the database. So let’s get rid of the archivelogs:

RMAN> change archivelog all uncatalog;

uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_15_d5q709b5_.arc RECID=46 STAMP=931256737
uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_16_d5q709x1_.arc RECID=41 STAMP=931256730
uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_17_d5q709oq_.arc RECID=43 STAMP=931256730
uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_18_d5q5q65p_.arc RECID=35 STAMP=931255414
uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_19_d5q6gtmj_.arc RECID=36 STAMP=931256170
uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_20_d5q6lm3q_.arc RECID=38 STAMP=931256291
uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_11_d5q709gs_.arc RECID=45 STAMP=931256735
uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_12_d5q709xo_.arc RECID=42 STAMP=931256730
uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_13_d5q709ln_.arc RECID=44 STAMP=931256731
uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_14_d5q709pq_.arc RECID=40 STAMP=931256729
uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_15_d5q6gg9k_.arc RECID=37 STAMP=931256158
uncataloged archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_16_d5q6l6jm_.arc RECID=39 STAMP=931256278
Uncataloged 12 objects

That worked. The files are still there but the database does not know that anymore. Now we can apply the policy in the way we want it:

RMAN> report obsolete;

RMAN retention policy will be applied to the command
RMAN retention policy is set to redundancy 2
Report of obsolete backups and copies
Type                 Key    Completion Time    Filename/Handle
-------------------- ------ ------------------ --------------------
Backup Set           23     22.12.2016 09:19:16
  Backup Piece       23     22.12.2016 09:19:16 /u01/app/oracle/fra/OLTP/43C6AA13C2390666E0538D24100A09EF/backupset/2016_12_22/o1_mf_nnndf_TAG20161222T091750_d5q33orv_.bkp
Backup Set           24     22.12.2016 09:19:30
  Backup Piece       24     22.12.2016 09:19:30 /u01/app/oracle/fra/OLTP/backupset/2016_12_22/o1_mf_annnn_TAG20161222T091930_d5q34ljw_.bkp
Backup Set           25     22.12.2016 09:19:34
  Backup Piece       25     22.12.2016 09:19:34 /u01/app/oracle/fra/OLTP/autobackup/2016_12_22/o1_mf_s_931252772_d5q34ol5_.bkp
Backup Set           26     22.12.2016 10:01:36
  Backup Piece       26     22.12.2016 10:01:36 /u01/app/oracle/fra/OLTP/backupset/2016_12_22/o1_mf_annnn_TAG20161222T100127_d5q5m88s_.bkp

The oldest backup is still obsolete, but now archivelogs anymore. That’s want we wannted to achieve. I can now remove the old backup:

RMAN> delete noprompt obsolete;

RMAN retention policy will be applied to the command
RMAN retention policy is set to redundancy 2
using channel ORA_DISK_1
Deleting the following obsolete backups and copies:
Type                 Key    Completion Time    Filename/Handle
-------------------- ------ ------------------ --------------------
Backup Set           23     22.12.2016 09:19:16
  Backup Piece       23     22.12.2016 09:19:16 /u01/app/oracle/fra/OLTP/43C6AA13C2390666E0538D24100A09EF/backupset/2016_12_22/o1_mf_nnndf_TAG20161222T091750_d5q33orv_.bkp
Backup Set           24     22.12.2016 09:19:30
  Backup Piece       24     22.12.2016 09:19:30 /u01/app/oracle/fra/OLTP/backupset/2016_12_22/o1_mf_annnn_TAG20161222T091930_d5q34ljw_.bkp
Backup Set           25     22.12.2016 09:19:34
  Backup Piece       25     22.12.2016 09:19:34 /u01/app/oracle/fra/OLTP/autobackup/2016_12_22/o1_mf_s_931252772_d5q34ol5_.bkp
Backup Set           26     22.12.2016 10:01:36
  Backup Piece       26     22.12.2016 10:01:36 /u01/app/oracle/fra/OLTP/backupset/2016_12_22/o1_mf_annnn_TAG20161222T100127_d5q5m88s_.bkp
deleted backup piece
backup piece handle=/u01/app/oracle/fra/OLTP/43C6AA13C2390666E0538D24100A09EF/backupset/2016_12_22/o1_mf_nnndf_TAG20161222T091750_d5q33orv_.bkp RECID=23 STAMP=931252741
deleted backup piece
backup piece handle=/u01/app/oracle/fra/OLTP/backupset/2016_12_22/o1_mf_annnn_TAG20161222T091930_d5q34ljw_.bkp RECID=24 STAMP=931252770
deleted backup piece
backup piece handle=/u01/app/oracle/fra/OLTP/autobackup/2016_12_22/o1_mf_s_931252772_d5q34ol5_.bkp RECID=25 STAMP=931252773
deleted backup piece
backup piece handle=/u01/app/oracle/fra/OLTP/backupset/2016_12_22/o1_mf_annnn_TAG20161222T100127_d5q5m88s_.bkp RECID=26 STAMP=931255288
Deleted 4 objects

Afterwards I can re-register the archivelogs.

RMAN> catalog recovery area noprompt;

searching for all files in the recovery area

List of Files Unknown to the Database
=====================================
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_20_d5q6lm3q_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_16_d5q6l6jm_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_15_d5q709b5_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_11_d5q709gs_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_13_d5q709ln_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_17_d5q709oq_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_14_d5q709pq_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_18_d5q5q65p_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_19_d5q6gtmj_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_15_d5q6gg9k_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_16_d5q709x1_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_12_d5q709xo_.arc
cataloging files...
cataloging done

List of Cataloged Files
=======================
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_20_d5q6lm3q_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_16_d5q6l6jm_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_15_d5q709b5_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_11_d5q709gs_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_13_d5q709ln_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_17_d5q709oq_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_14_d5q709pq_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_18_d5q5q65p_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_19_d5q6gtmj_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_15_d5q6gg9k_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_16_d5q709x1_.arc
File Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_12_d5q709xo_.arc

The archivelog files are back in the database catalog. Now I can handle them separately and apply any rule I want.

RMAN> delete noprompt archivelog until time 'sysdate-1/12';

released channel: ORA_DISK_1
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=279 instance=oltp_1 device type=DISK
List of Archived Log Copies for database with db_unique_name OLTP
=====================================================================

Key     Thrd Seq     S Low Time
------- ---- ------- - -------------------
49      1    15      A 21.12.2016 12:56:40
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_15_d5q709b5_.arc

50      2    11      A 21.12.2016 12:56:30
        Name: /u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_11_d5q709gs_.arc

deleted archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_1_15_d5q709b5_.arc RECID=49 STAMP=931257331
deleted archived log
archived log file name=/u01/app/oracle/fra/OLTP/archivelog/2016_12_22/o1_mf_2_11_d5q709gs_.arc RECID=50 STAMP=931257331
Deleted 2 objects

Not very straight forward, but it does the job.

Inspired by a comment on Twitter by Franck Pachot, the best way to keep a history of archivelogs is not to use “ALL” but “FROM”. So the approach the keep a history of three days would be the follwing:

RMAN> change archivelog from time 'sysdate-3' uncatalog;
RMAN> delete noprompt obsolete;
RMAN> catalog recovery area noprompt;

That way all archivelogs from the last three days are uncataloged. All other archivelogs are handled by the “delete obsolete” operation and there is no need to remove archivelogs manually.