How do I know the size of my redo log block?

The easy way to find redo block size is to get trace of redolog and read that.

1. Below one is done on solaris platform: Dump redolog:
2. Now check generated trace (it will under the same location where alert log is present)
3. So redolog block size in this database is of 512 bytes.

Can I have redo log groups with different size?

All members of the same multiplexed redo log group must be the same size. Members of different groups can have different sizes. However, there is no advantage in varying file size between groups.

How to create redo log groups in Oracle?

Creating Redo Log Groups To create a new group of redo log files, use the SQL statement ALTER DATABASE with the ADD LOGFILE clause. The following statement adds a new group of redo logs to the database: ALTER DATABASE ADD LOGFILE (‘/oracle/dbs/log1c.rdo’, ‘/oracle/dbs/log2c.rdo’) SIZE 100M;

How to check redo log size in Oracle?

V$LOG_HISTORY is used to check history of redo log generation in Oracle. V$LOGFILE is used to check the file name and location of redo logs. V$LOG and V$LOGFILE view can be combined to get the detailed information like redo log size, redo log members, thread, groups, sequence, status etc.

What does inactive redo log file in Oracle mean?

Redo log files that are no longer required for instance recovery are called inactive redo log files. If you have enabled archiving (the database is in ARCHIVELOG mode), then the database cannot reuse or overwrite an active online log file until one of the archiver background processes (ARC n) has archived its contents.

How many redo log files does a database need?

The redo log of a database consists of two or more redo log files. The database requires a minimum of two files to guarantee that one is always available for writing while the other is being archived (if the database is in ARCHIVELOG mode).

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