I’m briefly going to show you the recommended settings by both F5 and Oracle for a RAC Load Balancing setup. But it’s important to mention before implementing any configuration into production, always test since all environments are different, well most. It’s important to work with all teams who are in charge of the settings on the server side and Oracle side because there are buffer settings and timeouts that you will need. For example, see below for both Oracle 12c and the OS which in my case is RedHat 7:
Oracle 12c Defaults and Best Practice: TCP.CONNECT_TIMEOUT = 60 Seconds (F5 keeps mentioning that Oracle states this should be 10 seconds but I couldn’t find it anywhere. Even their best practice/tuning doc states 60) SQLNET.EXPIRE_TIME = 10 Minutes RECV_BUF_SIZE = OS Specific SEND_BUF_SIZE = OS Specific
From Oracle’s Best Practices for Database Performance and Scalability Guide:
Health Monitor: Interval = TCP.CONNECT_TIMEOUT x 3 + 1 (60 x 3 + 1= 181)
Work with your Oracle DB’s to get the Send, Receive, Connecting Strings.
Receive Row/Receive Column is used for returns from the SQL query that may have multiple results. I used 1.
Pool: Action On Service Down = Reject Load Balancing Method = Least Connection(node) Priority Group Activiation = Less Than Available Members = set to 1 :this is the minimum number of nodes at a specific Priority Level that should be available before the pool chooses a lower priority level
Add the member nodes and don’t forget to give them specific Priorities. In this case PRIMARY=100 STANDBY=50
There are two TCP Profiles, one for the Client and one for the Server.
Maximum Syn Retransmissions = TCP.CONNECT_TIMEOUT = 60 Seconds = DID NOT TOUCH Idle Timeout = SQLNET.EXPIRE_TIME = 10 Minutes = Changed to 660 which equals 11 Minutes since it needs to be slightly larger Send Buffer = SEND_BUF_SIZE = OS Dependent = For me I’m looking at RedHat Linux 7 which is 256K but I set the F5 to RedHat’s max Receive Window = RECV_BUF_SIZE = OS Dependent = For me I’m looking at RedHat Linux 7 which is 256K but I set the F5 to RedHat’s max