Oracle Applications 11i Load Balancing does not work with RAC one Node

Question

Hi all,
Could you help me to resolve this issue.
Architecture environment is :
- One APPS tier node
- Two nodes Oracle Database Appliance (Primary node 1 holds INSTANCE_1 et Secondary node is configurured to holds INSTANCE_2), i.e RAC one Node.
- The primary node have instance_name SIGM_1 and the secondary node have instance_name SIGM_2, but in RAC one node, the secondary instance is not alive.
We convert our EBS 11i environment to RAC following note ID Using Oracle 11g Release 2 Real Application Clusters with Oracle E-Business Suite Release 11i [ID 823586.1].
When testing Database failover, Oracle Applications 11i load balancing does not work anymore.
The root cause is that, when the primary node of the Rac one node is down, the INSTANCE_NAME_1 is automaically relocating to the surviving node,.
During test failover, we imagine that when the primary node goes down, the secondary node start or relocate database with instance_name SIGM_2, and in that case the Oracle Applications load balancing works.
Currently, when the primary node goes down, the instance_name SIGM_1 is relocated on the secondary node, which cause failure of Oracle Applications Load Balancing.
Thank you for your advice.
Moussa

Answer 1

This is something I observed a long time ago for Safari (ie: around version 1). I'm not sure this is Safari, per se, but OpenSSL that is responsible for the behavior. I'm pretty sure Chrome does this and I've seen some Linux browsers do it.
What I have done at the last two companies I've worked for is recommend that our clients do not use SSL SessionID as the way of tracking sticky sessions on web servers, but instead using IP address. This works in nearly all cases and has few downsides. The other solution is to use some sort of session sharing on your web servers to mitigate the issue (which also means that your web servers aren't a point of failure for your users' sessions). (One of the products I supported had no session information stored on the web servers, so we could safely round-robin requests, the other product could be implemented with a Session State Server... but in most cases we just used IP address to load balance with). The other solution is to configure your load balancer to terminate the SSL tunnel. You get some other benefits from this, such as allowing your load balancer to reduce the number of actual connections to the web servers. I've seen many devices setup this way.
One thing to consider through this is that - due to the way internet standards work - this really can't be termed a bug on anyone's part. There is no guarantee in the SSL/TLS standards that a client will return the same SSL Session ID for each request and there is not requirement that subsequent requests will even use the same tunnel. Remember, HTTP is a stateless protocol. Each request is considered a new request by the web server and everything else is just trickery to try and get it to work the way you want. You can be annoyed at Safari's behavior, but it's been this way for over 5 years by my count, so I don't expect it to change.