standby redo logs creation

[Roshan]

source server: Oracle DB 12.1.0.2 RAC 2 nodes (A)
target server: Oracle DB 12.1.0.2 standalone. (B) standby database.

Hi Erman,

I am configuring a dataguard from source server to target. Oracle Golden Gate replication is configured from  another RAC database to the source server (A) using downstream replication.

From A:

1 ONLINE +DATA/DWARE1/ONLINELOG/group_1.339.1018688715 NO 0
2 ONLINE +DATA/DWARE1/ONLINELOG/group_2.340.1018688733 NO 0
3 ONLINE +DATA/DWARE1/ONLINELOG/group_3.347.1018688743 NO 0
4 ONLINE +DATA/DWARE1/ONLINELOG/group_4.348.1018688759 NO 0
16 ONLINE +DATA/DWARE1/ONLINELOG/group_16.542.1018688805 NO 0
17 ONLINE +DATA/DWARE1/ONLINELOG/group_17.543.1018688819 NO 0
18 ONLINE +DATA/DWARE1/ONLINELOG/group_18.544.1018688833 NO 0
19 ONLINE +DATA/DWARE1/ONLINELOG/group_19.545.1018688847 NO 0
21 STANDBY +DATA/DWARE1/ONLINELOG/group_21.334.1018650713 NO 0
22 STANDBY +DATA/DWARE1/ONLINELOG/group_22.333.1018650717 NO 0
23 STANDBY +DATA/DWARE1/ONLINELOG/group_23.352.1018650719 NO 0
24 STANDBY +DATA/DWARE1/ONLINELOG/group_24.332.1018650723 NO 0
25 STANDBY +DATA/DWARE1/ONLINELOG/group_25.331.1018650727 NO 0
26 STANDBY +DATA/DWARE1/ONLINELOG/group_26.330.1018650731 NO 0
27 STANDBY +DATA/DWARE1/ONLINELOG/group_27.329.1018650733 NO 0
28 STANDBY +DATA/DWARE1/ONLINELOG/group_28.328.1018650737 NO 0
29 STANDBY +DATA/DWARE1/ONLINELOG/group_29.327.1018650741 NO 0
30 STANDBY +DATA/DWARE1/ONLINELOG/group_30.326.1018650745 NO 0
31 STANDBY +DATA/DWARE1/ONLINELOG/group_31.325.1018650749 NO 0
32 STANDBY +DATA/DWARE1/ONLINELOG/group_32.324.1018650751 NO 0
33 STANDBY +DATA/DWARE1/ONLINELOG/group_33.323.1018650755 NO 0
34 STANDBY +DATA/DWARE1/ONLINELOG/group_34.322.1018650759 NO 0
35 STANDBY +DATA/DWARE1/ONLINELOG/group_35.321.1018650763 NO 0
36 STANDBY +DATA/DWARE1/ONLINELOG/group_36.320.1018650767 NO 0
37 STANDBY +DATA/DWARE1/ONLINELOG/group_37.319.1018650769 NO 0
38 STANDBY +DATA/DWARE1/ONLINELOG/group_38.318.1018650773 NO 0
39 STANDBY +DATA/DWARE1/ONLINELOG/group_39.317.1018650777 NO 0
40 STANDBY +DATA/DWARE1/ONLINELOG/group_40.316.1018650781 NO 0
41 STANDBY +DATA/DWARE1/ONLINELOG/group_41.315.1018650783 NO 0
42 STANDBY +DATA/DWARE1/ONLINELOG/group_42.312.1018650787 NO 0
5 ONLINE +DATA/DWARE1/ONLINELOG/group_5.512.1018688105 NO 0
6 ONLINE +DATA/DWARE1/ONLINELOG/group_6.511.1018688121 NO 0
7 ONLINE +DATA/DWARE1/ONLINELOG/group_7.534.1018688135 NO 0
8 ONLINE +DATA/DWARE1/ONLINELOG/group_8.533.1018688149 NO 0
9 ONLINE +DATA/DWARE1/ONLINELOG/group_9.535.1018688171 NO 0
10 ONLINE +DATA/DWARE1/ONLINELOG/group_10.536.1018688189 NO 0
11 ONLINE +DATA/DWARE1/ONLINELOG/group_11.537.1018688207 NO 0
12 ONLINE +DATA/DWARE1/ONLINELOG/group_12.538.1018688223 NO 0
13 ONLINE +DATA/DWARE1/ONLINELOG/group_13.539.1018688235 NO 0
14 ONLINE +DATA/DWARE1/ONLINELOG/group_14.540.1018688249 NO 0
15 ONLINE +DATA/DWARE1/ONLINELOG/group_15.541.1018688259 NO 0
20 ONLINE +DATA/DWARE1/ONLINELOG/group_20.546.1018688857 NO 0

export.xlsx

Can you please advise if I should proceed to create the standby redo logs on A again or only B?

Thanks,

Roshan

[ErmanArslansOracleBlog]

Normally, you should create standby redo logs on both the standby and the primary database ( to be prepared for a future switch-over)

But, I guess you already know that? If so, please revise your question Roshan.

[Roshan]

source server ----downstream replication (golden gate) ---- server A (standby redo logs already created for downstream replication) ---- standby DB

As shown above, the standby redo logs were already created on primary node A (for golden gate downstream replication). Does this mean there is no need to create any additional standby redo logs?

[ErmanArslansOracleBlog]

The Dataguard role transition will occur between A and B. So if the required standby redologs in A are already created and configured to support this configuration, and yes. Yo don't need to create additional standby redologs in A.
You already know the requirements for standby redologs.. The size and the count.. So check accordingly and decide.

[Roshan]

Thanks Erman.

[ErmanArslansOracleBlog]

Read this -> https://docs.oracle.com/cd/B19306_01/server.102/b14239/create_ps.htm
This is for 10G but still okay.

Read the section 3.1.3 ->

Step 1   Ensure log file sizes are identical on the primary and standby databases.

Step 2   Determine the appropriate number of standby redo log file groups.

It is written there..
So you should ensure that the standby redolog setup can support a dataguard switchover between the related primary and standby databases.. (as I already told you)

[Roshan]

If after performing the restore/duplicate, should I recreate the standby redologs on target? Or should I only start replication?
run {
 allocate channel pri1 type disk;
 allocate channel pri2 type disk;
 allocate channel prmy4 type disk;
 allocate auxiliary channel stby type disk;
 duplicate target database for standby from active database
DORECOVER
  spfile
    set db_unique_name='hrsty'
    set control_files='/data/DATA/dware1/control01.ctl','/data/DATA/dware1/control02.ctl'
    set fal_client='dwaredr'
    set fal_server='dware1'
 set log_archive_max_processes='5'
    set standby_file_management='AUTO'
    set log_archive_config='dg_config=(dware1,dwaredr)'
 set db_file_name_convert='+DATA/DWARE1/DATAFILE','/data/DATA/dware1'
    set log_file_name_convert='+DATA/DWARE1/DATAFILE','/data/DATA/dware1/log'
set newname for tempfile 1 to '/archive/ARC/temp01.dbf'
set newname for tempfile 2 to '/archive/ARC/temp02.dbf'
set newname for tempfile 3 to '/archive/ARC/temp03.dbf'
set newname for tempfile 4 to '/archive/ARC/temp04.dbf'
    set log_archive_dest_1='LOCATION=/archive/ARC/ VALID_FOR=(ALL_LOGFILES,ALL_ROLES) DB_UNIQUE_NAME=dwaredr'
   
  }
 
 

[ErmanArslansOracleBlog]

If the standby redologs are not present (with the required size and count) then yes you need to recreate.
Do your restore and check the situation.