Hi,
Oracle recommends to have one more standby redo log group per thread than total number of redo log groups per thread on primary. For example, if my primary database has one thread and total 4 redo log groups, my physical standby should have 5 standby redo log groups.
Oracle says that "it reduces the likelihood that the primary instance's log writer (LGWR) process will be blocked because a standby redo log file cannot be allocated on the standby database."
I really don't understand this statement that how LGWR on primary can get blocked because standby is not able to allocated standby redo log, and how one more group can avoid this problem?
Appreciate if someone can help to understand this scenario.
SAQ