I think you are trying to dance on the head of pin here.
OPINION…….
There is nothing anywhere that determines from a contractual perspective when a
Standby Database exists.
We can look at it from a technical perspective and state a standby database
exists as soon as there is a complete database with a standby controlfile.
https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#SBYDB4722
Table 3-2 Creating a Physical Standby Database
Reference
Task
Database
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i70835>
Section 3.2.1
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i70835>
Create a Backup Copy of the Primary Database Datafiles
Primary
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i68937>
Section 3.2.2
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i68937>
Create a Control File for the Standby Database
Primary
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i70517>
Section 3.2.3
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i70517>
Create a Parameter File for the Standby Database
Primary
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i58318>
Section 3.2.4
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i58318>
Copy Files from the Primary System to the Standby System
Primary
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i72105>
Section 3.2.5
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i72105>
Set Up the Environment to Support the Standby Database
Standby
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i57454>
Section 3.2.6
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i57454>
Start the Physical Standby Database
Standbyç========
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i77231>
Section 3.2.7
<https://docs.oracle.com/cd/E11882_01/server.112/e41134/create_ps.htm#i77231>
Verify the Physical Standby Database Is Performing Properly
Standby
At section 3.2.6 we can say the physical standby exists using Oracle’s own
words as to when it is startable.
It is a little different when it is a previous primary. After failover
technically speaking it is not a standby until you do the role transition of
primary to standby and at that point then the byte is flipped in the
controlfile to be a standby controlfile and v$database shows STANDBY in the
controlfile_type column.
From a technical perspective I believe you are on fairly firm grounds that it
is not a standby any more until the role transition happens on that old primary
and the controlfile becomes a standby controlfile. At this point the database
looks no different than a recovered backup, except for the transactions in the
online redologs and it is a regular controlfile instead of a backup
controlfile. Also I have had production database with disabled standby
configurations and no standby exists anywhere to go with that configuration.
Assuming that to be true then as long as you disable BCT before the role
transition on the original primary to be a standby then you should be within
contractual compliance.
This is where you are really dancing on the head of the pin.
1. You have to argue and justify that you are within contractual
compliance instead of not using BCT and being in the clear.
2. You have to ensure that no DBA in your company ever makes a mistake
and misses removing the BCT before the role transition from primary to standby.
If it is ever removed after role transition then you are technically in
violation.
3. You have to ensure no one ever turns on full Data Guard automation
causing the role transition of primary to standby automatically.
4. You have to remember to enable it on the new primary side after
failover.
On a side note you would need to check that you can remove block change
tracking when the database is in the crashed state, before transitioning
primary to standby. I have never executed the command at that exact point.
I think you are simply setting yourself up for failure. You have limited
yourself in full use of the Data Guard features (full automation) and you are
expecting humans to be perfect. There are too many places where the human can
make a mistake and make your company in non-compliance of your Oracle licenses.
My opinion.
Matthew Parker
Chief Technologist
Dimensional DBA
425-891-7934 (cell)
D&B 047931344
CAGE 7J5S7
<mailto:Dimensional.dba@xxxxxxxxxxx> Dimensional.dba@xxxxxxxxxxx
<http://www.linkedin.com/pub/matthew-parker/6/51b/944/> View Matthew Parker's
profile on LinkedIn
<http://www.dimensionaldba.com/> www.dimensionaldba.com
From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On ;
Behalf Of Chirag Shah
Sent: Friday, February 19, 2016 2:54 AM
To: Oracle L
Subject: Block Change Tracking + Stand By DB and Switch Over
Hello Experts,
For BCT in standby, we need to have Active Data Guard License as per the Doc ID
468576.1 ,"You can only enable block change tracking at a physical standby
database if a license for the Oracle Active Data Guard option is enabled."
But what happen if we switch over role while having BCT file on Primary DB and
do not have Active Dataguard license ?
We don't use recovery catalogue and taking backups only from Primary DB with
control file as RMAN repository. If we switch over to standby then do we also
require to create BCT file to New primary DB ? then both the Primary and
Standby DBs would have BCT files..?? so in that case shall we need to disable
BCT before switch over ?
We are on 11g (11.2.0.3) with one Physical Standby DB
Any thoughts.. ? Thanks in advance..
Thanks & Regards,
CS
