Duplication: divide et impera

Posted in: Technical Track

For me, every Monday morning starts with the same routine. I refresh some QA databases from PeopleSoft production one. Even though the process is almost fully automated (all commands are automatically generated) it takes several hours to perform the final steps because DUPLICATE FROM ACTIVE DATABASE performs image copies to the destination server.

I am so happy now because the DUPLICATE mechanism in #DB12C has been changed. It now uses PULL method and backup sets over the  network to perform duplication from an active database. This will shorten the time of the operation since “USING COMPRESSED BACKUPSET” and “SECTION SIZE” can now be used to optimize the process.

I wanted to start the post and provide results of duplicate and output for the operation. However, the real functionality of new features sometimes deviates from what is claimed. The reasons for the discrepancies can vary, from version restrictions to bugs, but the bottom line is that the results are not what’s expected.

That’s why many DBAs are very careful about new features. No, not afraid, just careful. They need to make 100% sure that what was claimed is working properly, without problems, so it can be properly implemented on the systems they support and care about. There are no plans that I am aware of yet to implement a 12c database on any servers; however, I decided to test duplication on an active database to see how compressed backup sets and section size clauses influence the process…in case I am asked about it one day…

I started with a 12c 2 nodes RAC database. The duplication without compression and usage of section size went well, but failed due to a missing log error with section size and compression. I thought it might be because I used an easy naming connection instead of TNS, but I tested it with TNS and got the same result. I decided to test it for a standalone database – got the same result. It was failing on recovery of the duplicated database every time I used either COMPRESSED BACKUPSET and/or SECTION SIZE clauses independent of the type of connection string I was using – ASM or file system – but duplication with the clauses worked without any issues.

Even though I haven’t resolved the issue, the story isn’t over. I created SR on MOS, uploaded the required trace and log files, and am waiting for their response. I hope someone made it work, but I have not heard yet that anyone has.  It will definitely work one day and the error I have been receiving will be overcome:

RMAN-06402: Oracle instance shut down
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03002: failure of Duplicate Db command at 09/08/2013 20:14:10
RMAN-05501: aborting duplication of target database
RMAN-03015: error occurred in stored script Memory Script
RMAN-06053: unable to perform media recovery because of missing log
RMAN-06025: no backup of archived log for thread 1 with sequence 67 and starting SCN of 2178389 found to restore

And I will be able to perform active duplication of 12c databases with compressed and section size to receive the output similar to the
one without the clauses:

[[email protected] ~]$ rman target sys/[email protected] auxiliary sys/[email protected]
Recovery Manager: Release 12.1.0.1.0 - Production on Fri Sep 6 11:47:06 2013
Copyright (c) 1982, 2013, Oracle and/or its affiliates.  All rights reserved.
connected to target database: T12 (DBID=1222223202)
connected to auxiliary database: T12 (not mounted)
RMAN> duplicate target database to c12 from active database
spfile
parameter_value_convert 't12', 'c12'
set db_file_name_convert 't12', 'c12'
set log_file_name_convert 't12', 'c12'
nofilenamecheck;2> 3> 4> 5> 6>
Starting Duplicate Db at 06-SEP-13
using target database control file instead of recovery catalog
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=21 device type=DISK
current log archived
contents of Memory Script:
{
   restore clone from service  't12' spfile to
 '/u01/app/oracle/product/12.1.0/dbhome_2/dbs/spfilec12.ora';
   sql clone "alter system set spfile= ''/u01/app/oracle/product/12.1.0/dbhome_2/dbs/spfilec12.ora''";
}
executing Memory Script
Starting restore at 06-SEP-13
using channel ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: using network backup set from service t12
channel ORA_AUX_DISK_1: restoring SPFILE
output file name=/u01/app/oracle/product/12.1.0/dbhome_2/dbs/spfilec12.ora
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:03
Finished restore at 06-SEP-13
sql statement: alter system set spfile= ''/u01/app/oracle/product/12.1.0/dbhome_2/dbs/spfilec12.ora''
contents of Memory Script:
{
   sql clone "alter system set  db_name =
 ''C12'' comment=
 ''duplicate'' scope=spfile";
   sql clone "alter system set  audit_file_dest =
 ''/u01/app/oracle/admin/c12/adump'' comment=
 '''' scope=spfile";
   sql clone "alter system set  control_files =
 ''/u01/oradata/c12/control01.ctl'', ''/u01/app/oracle/fast_recovery_area/c12/control02.ctl'' comment=
 '''' scope=spfile";
   sql clone "alter system set  dispatchers =
 ''(PROTOCOL=TCP) (SERVICE=c12XDB)'' comment=
 '''' scope=spfile";
   sql clone "alter system set  db_file_name_convert =
 ''t12'', ''c12'' comment=
 '''' scope=spfile";
   sql clone "alter system set  log_file_name_convert =
 ''t12'', ''c12'' comment=
 '''' scope=spfile";
   shutdown clone immediate;
   startup clone nomount;
}
executing Memory Script
sql statement: alter system set  db_name =  ''C12'' comment= ''duplicate'' scope=spfile
sql statement: alter system set  audit_file_dest =  ''/u01/app/oracle/admin/c12/adump'' comment= '''' scope=spfile
sql statement: alter system set  control_files =  ''/u01/oradata/c12/control01.ctl'', ''/u01/app/oracle/fast_recovery_area/c12/control02.ctl'' comment= '''' scope=spfile
sql statement: alter system set  dispatchers =  ''(PROTOCOL=TCP) (SERVICE=c12XDB)'' comment= '''' scope=spfile
sql statement: alter system set  db_file_name_convert =  ''t12'', ''c12'' comment= '''' scope=spfile
sql statement: alter system set  log_file_name_convert =  ''t12'', ''c12'' comment= '''' scope=spfile
Oracle instance shut down
connected to auxiliary database (not started)
Oracle instance started
Total System Global Area     626327552 bytes
Fixed Size                     2291472 bytes
Variable Size                507513072 bytes
Database Buffers             113246208 bytes
Redo Buffers                   3276800 bytes
contents of Memory Script:
{
   sql clone "alter system set  db_name =
 ''T12'' comment=
 ''Modified by RMAN duplicate'' scope=spfile";
   sql clone "alter system set  db_unique_name =
 ''C12'' comment=
 ''Modified by RMAN duplicate'' scope=spfile";
   shutdown clone immediate;
   startup clone force nomount
   restore clone from service  't12' primary controlfile;
   alter clone database mount;
}
executing Memory Script
sql statement: alter system set  db_name =  ''T12'' comment= ''Modified by RMAN duplicate'' scope=spfile
sql statement: alter system set  db_unique_name =  ''C12'' comment= ''Modified by RMAN duplicate'' scope=spfile
Oracle instance shut down
Oracle instance started
Total System Global Area     626327552 bytes
Fixed Size                     2291472 bytes
Variable Size                507513072 bytes
Database Buffers             113246208 bytes
Redo Buffers                   3276800 bytes
Starting restore at 06-SEP-13
allocated channel: ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: SID=19 device type=DISK
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: using network backup set from service t12
channel ORA_AUX_DISK_1: restoring control file
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:15
output file name=/u01/oradata/c12/control01.ctl
output file name=/u01/app/oracle/fast_recovery_area/c12/control02.ctl
Finished restore at 06-SEP-13
database mounted
contents of Memory Script:
{
   set newname for datafile  1 to
 "/u01/oradata/c12/system01.dbf";
   set newname for datafile  2 to
 "/u01/oradata/c12/test01.dbf";
   set newname for datafile  3 to
 "/u01/oradata/c12/sysaux01.dbf";
   set newname for datafile  4 to
 "/u01/oradata/c12/undotbs01.dbf";
   set newname for datafile  6 to
 "/u01/oradata/c12/users01.dbf";
   restore
   from service  't12'   clone database
   ;
   sql 'alter system archive log current';
}
executing Memory Script
executing command: SET NEWNAME
executing command: SET NEWNAME
executing command: SET NEWNAME
executing command: SET NEWNAME
executing command: SET NEWNAME
Starting restore at 06-SEP-13
using channel ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: using network backup set from service t12
channel ORA_AUX_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_1: restoring datafile 00001 to /u01/oradata/c12/system01.dbf
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:01:35
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: using network backup set from service t12
channel ORA_AUX_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_1: restoring datafile 00002 to /u01/oradata/c12/test01.dbf
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:03:55
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: using network backup set from service t12
channel ORA_AUX_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_1: restoring datafile 00003 to /u01/oradata/c12/sysaux01.dbf
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:01:16
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: using network backup set from service t12
channel ORA_AUX_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_1: restoring datafile 00004 to /u01/oradata/c12/undotbs01.dbf
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:07
channel ORA_AUX_DISK_1: starting datafile backup set restore
channel ORA_AUX_DISK_1: using network backup set from service t12
channel ORA_AUX_DISK_1: specifying datafile(s) to restore from backup set
channel ORA_AUX_DISK_1: restoring datafile 00006 to /u01/oradata/c12/users01.dbf
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:07
Finished restore at 06-SEP-13
sql statement: alter system archive log current
current log archived
contents of Memory Script:
{
   restore clone force from service  't12'
           archivelog from scn  2035520;
   switch clone datafile all;
}
executing Memory Script
Starting restore at 06-SEP-13
using channel ORA_AUX_DISK_1
channel ORA_AUX_DISK_1: starting archived log restore to default destination
channel ORA_AUX_DISK_1: using network backup set from service t12
channel ORA_AUX_DISK_1: restoring archived log
archived log thread=1 sequence=57
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:01
channel ORA_AUX_DISK_1: starting archived log restore to default destination
channel ORA_AUX_DISK_1: using network backup set from service t12
channel ORA_AUX_DISK_1: restoring archived log
archived log thread=1 sequence=58
channel ORA_AUX_DISK_1: restore complete, elapsed time: 00:00:01
Finished restore at 06-SEP-13
datafile 1 switched to datafile copy
input datafile copy RECID=6 STAMP=825422144 file name=/u01/oradata/c12/system01.dbf
datafile 2 switched to datafile copy
input datafile copy RECID=7 STAMP=825422144 file name=/u01/oradata/c12/test01.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=8 STAMP=825422145 file name=/u01/oradata/c12/sysaux01.dbf
datafile 4 switched to datafile copy
input datafile copy RECID=9 STAMP=825422145 file name=/u01/oradata/c12/undotbs01.dbf
datafile 6 switched to datafile copy
input datafile copy RECID=10 STAMP=825422145 file name=/u01/oradata/c12/users01.dbf
contents of Memory Script:
{
   set until scn  2035798;
   recover
   clone database
    delete archivelog
   ;
}
executing Memory Script
executing command: SET until clause
Starting recover at 06-SEP-13
using channel ORA_AUX_DISK_1
starting media recovery
archived log for thread 1 with sequence 57 is already on disk as file /u01/oradata/arch/1_57_825025894.dbf
archived log for thread 1 with sequence 58 is already on disk as file /u01/oradata/arch/1_58_825025894.dbf
archived log file name=/u01/oradata/arch/1_57_825025894.dbf thread=1 sequence=57
archived log file name=/u01/oradata/arch/1_58_825025894.dbf thread=1 sequence=58
media recovery complete, elapsed time: 00:00:01
Finished recover at 06-SEP-13
Oracle instance started
Total System Global Area     626327552 bytes
Fixed Size                     2291472 bytes
Variable Size                507513072 bytes
Database Buffers             113246208 bytes
Redo Buffers                   3276800 bytes
contents of Memory Script:
{
   sql clone "alter system set  db_name =
 ''C12'' comment=
 ''Reset to original value by RMAN'' scope=spfile";
   sql clone "alter system reset  db_unique_name scope=spfile";
}
executing Memory Script
sql statement: alter system set  db_name =  ''C12'' comment= ''Reset to original value by RMAN'' scope=spfile
sql statement: alter system reset  db_unique_name scope=spfile
Oracle instance started
Total System Global Area     626327552 bytes
Fixed Size                     2291472 bytes
Variable Size                507513072 bytes
Database Buffers             113246208 bytes
Redo Buffers                   3276800 bytes
sql statement: CREATE CONTROLFILE REUSE SET DATABASE "C12" RESETLOGS ARCHIVELOG
  MAXLOGFILES     16
  MAXLOGMEMBERS      3
  MAXDATAFILES      100
  MAXINSTANCES     8
  MAXLOGHISTORY      292
 LOGFILE
  GROUP   1 ( '/u01/oradata/c12/redo01.log' ) SIZE 50 M  REUSE,
  GROUP   2 ( '/u01/oradata/c12/redo02.log' ) SIZE 50 M  REUSE,
  GROUP   3 ( '/u01/oradata/c12/redo03.log' ) SIZE 50 M  REUSE
 DATAFILE
  '/u01/oradata/c12/system01.dbf'
 CHARACTER SET WE8MSWIN1252
contents of Memory Script:
{
   set newname for tempfile  1 to
 "/u01/oradata/c12/temp01.dbf";
   switch clone tempfile all;
   catalog clone datafilecopy  "/u01/oradata/c12/test01.dbf",
 "/u01/oradata/c12/sysaux01.dbf",
 "/u01/oradata/c12/undotbs01.dbf",
 "/u01/oradata/c12/users01.dbf";
   switch clone datafile all;
}
executing Memory Script
executing command: SET NEWNAME
renamed tempfile 1 to /u01/oradata/c12/temp01.dbf in control file
cataloged datafile copy
datafile copy file name=/u01/oradata/c12/test01.dbf RECID=1 STAMP=825422173
cataloged datafile copy
datafile copy file name=/u01/oradata/c12/sysaux01.dbf RECID=2 STAMP=825422173
cataloged datafile copy
datafile copy file name=/u01/oradata/c12/undotbs01.dbf RECID=3 STAMP=825422174
cataloged datafile copy
datafile copy file name=/u01/oradata/c12/users01.dbf RECID=4 STAMP=825422174
datafile 2 switched to datafile copy
input datafile copy RECID=1 STAMP=825422173 file name=/u01/oradata/c12/test01.dbf
datafile 3 switched to datafile copy
input datafile copy RECID=2 STAMP=825422173 file name=/u01/oradata/c12/sysaux01.dbf
datafile 4 switched to datafile copy
input datafile copy RECID=3 STAMP=825422174 file name=/u01/oradata/c12/undotbs01.dbf
datafile 6 switched to datafile copy
input datafile copy RECID=4 STAMP=825422174 file name=/u01/oradata/c12/users01.dbf
contents of Memory Script:
{
   Alter clone database open resetlogs;
}
executing Memory Script
database opened
Finished Duplicate Db at 06-SEP-13

As you can see, the duplication has been nicely done and PULL method was used to get backup sets over the network from the source database. I assume with SDU set to its maximum value of 2Mb in #DB12C it can increase the speed of duplication and decrease the time I need to wait to complete post clone steps.

Thank you for reading the post and I hope to update it soon with a response from Oracle Support.

On another note, how many of you who blog bring such “unresolved” issues to the public? Do you think it’s worth publishing or better to wait until the issue has been resolved, post successful solutions, and leave it for investigation on support sites and within communities?

Happy duplicating!

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1 Comment. Leave new

Andrey Goryunov
September 24, 2013 1:20 am

I got an update from Oracle that there is a bug 16020213 and it is going to be fixed in 12.1.0.2 and workaround for now is not to use SECTION SIZE

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