Before creating standby database, you need to consider where your standby database files will be located and make sure the filesystem has necessary paths available and pre-created.
Dbvisit will create standby database files regardless whether on ASM, Filesystem or ACFS according to the general Oracle rules and concept. The main consideration here is always whether you will do file path conversion or not.
If you don’t know which type of files your primary database is using, be sure to check https://dbvisit.atlassian.net/wiki/spaces/DSMP/pages/3806167060/Prerequisites#5.-Check-Primary-Database-Files-Naming-Structure
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1 OMF files
Location of OMF files on standby server is completely driven by OMF parameters db_create_file_dest , db_create_online_log_dest_[x] and db_recovery_file_dest. You may change it to place your files on different ASM diskgroup, different filesystem mountpoint etc … OMF parameters on primary and standby are needed even if you don’t make any type of name/path conversion.
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db_create_file_dest db_create_online_log_dest_1 db_create_online_log_dest_2 db_create_online_log_dest_3 db_create_online_log_dest_4 db_create_online_log_dest_5 |
If db_create_online_log_dest_[x] is not set, Oracle creates redo in db_create_file_dest and creates automatically mirror in db_recovery_file_dest
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Don’t forget that Oracle automatically adds db_unique_name to the OMF path. Never set OMF parameters to contain any actual name. For example if you would set db_create_online_log_dest_1 = /u02/app/oracle/oradata/DEV, you would end up with nonsense path: |
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You will need to set OMF parameters when creating standby database to the same values as on your primary (this is done automatically during create standby database wizard)
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OMF parameters db_create_file_dest, db_recovery_file_dest or db_create_online_log_dest_[x] are needed even if your standby file locations are the same as on primary. They will be automatically copied from your current primary database init parameters during create standby database process. |
If you would like to have different file paths on primary and standby or if you’re converting between ASM and filesystem (path conversion is done):
You will need to set OMF parameters when creating standby database to intended locations
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as described further
Following rules will apply for different types of files when standby database is created:
OMF datafiles and tempfiles
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db_unique_name is converted by oracle to capital letters uppercase for filesystem location. |
OMF redo logs
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During create standby database we would set OMF parameters like so:
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Unique db name for standby database is set during DDC configuration creation, cannot be set during create standby database process |
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db_file_name_convert and log_file_name_convert must not be set |
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control_files parameter is not set as controlfiles are OMFis not set as controlfiles are OMF |
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Unique db name for standby database is set during DDC configuration creation, cannot be set during create standby database process |
After standby database is created it will have following structure:
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Redo member locations will still point to ASM with primary db_unique_name on standby database. This is expected, the paths will be changed only during activation or graceful switchover |
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If you would like to have different file paths on primary and standby or if you’re converting between ASM and filesystem (path conversion is done):
Such conversion is possible, but you You need to set the convert parameters for your standby database during standby database creation. There are two convert parameters to set:
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db_file_name_convert = 'PATHA','PATHB','PATHC','PATHD',... log_file_name_convert = 'PATHA','PATHB','PATHC','PATHD',... |
The convert parameters have following properties:
They contain pair or pairs of strings which are used for path conversion when standby database is created
They are valid on standby database only. On primary, they are not effective.
They are For Dbvisit to work properly, tey need always set on primary and standby - (their values are reversed)
Primary filesystem to Standby filesystem conversion example with non-OMF files
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You will need to set OMF parameters when creating standby database to the same values as on your primary (this is done automatically during create standby database wizard)
There’s no need to set any specific parameters for non-OMF files
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