How many maximum Redo Logfiles one can have in a Database?

How many maximum Redo Logfiles one can have in a Database?
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1 Answer

Answer :

Maximum number of logfiles is limited by value of MAXLOGFILES parameter in the CREATE DATABASE statement.  Control file can be resized to allow more entries; ultimately an operating system limit. Maximum number of  logfiles per group - Unlimited
Consider the parameters that can limit the number of redo log files before setting up or altering the configuration  of an instance redo log.
The following parameters limit the number of redo log files that you can add to a database: MAXLOGFILES &  MAXLOGMEMBERS.
The MAXLOGFILES parameter used in the CREATE DATABASE statement determines the maximum number of  groups of redo log files for each database. Group values can range from 1 to MAXLOGFILES. When the compatibility level is set earlier than 10.2.0, the only way to override this upper limit is to re-create the  database or its control file. Therefore, it is important to consider this limit before creating a database. When compatibility is set to 10.2.0 or later, you can exceed the MAXLOGFILES limit, and the control files expand as  needed.
If MAXLOGFILES is not specified for the CREATE DATABASE statement, then the database uses an operating system  specific default value.
The MAXLOGMEMBERS parameter used in the CREATE DATABASE statement determines the maximum number of  members for each group. As with MAXLOGFILES, the only way to override this upper limit is to re-create the  database or control file. Therefore, it is important to consider this limit before creating a database. If no MAXLOGMEMBERS parameter is specified for the CREATE DATABASE statement, then the database uses an  operating system default value.
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