Checking Redo Log Switch and Redo Generating by Session

Focus of this article is to check the redo log switch frequency as well as the sessions causing huge redo logs generation. A sudden surge in archived log generation can make DBA look into the issue to find out since when redo log generation has spiked. Following is the query we can easily find everywhere on the internet to find out the redo logs switch frequency. Of course this is not written by me. I do not know who is the original writer of this query therefore I can refer to that great guy or website.

Dataguard out of sync OR Log shipping not working

 You can seek help from this (single node) and this (RAC) document for setting up dataguard. But if dataguard has become out of sync, there are several things that you might need to look at before you fix it. In the following I am providing a checklist that you can take a look to find out the issue and thus implement a solution.