Hi,
I am trying to get clear in my mind if the rather loose use of the term Affinity means the same thing in most cases.
Q1. I have seen the various terms - RAC Affinity, Node Affinity, Instance Affinity, Application Affinity. Do these mean the same thing ?
To my mind they all basically mean associating a database connection ( be it a client connection, a mid tier connection or an application connection ) to a particular / preferred RAC Instance.
Q2. When we talk about Affinity in the context of Q1, is this effectively achieved / set up using Oracle Services ?
Q3. We we say Affinity do we mean Preference rather than Mandatory choice - since if it was a hard mandatory choice to use say a particular node / instance, then there would be little point in clustering in the first place ? ( i.e. are we saying - if the node / instance is available then use that, otherwise uise what is available ? )
Q4. I do not see any difference in the terms Node and Instance Affinity - since the Instance is inextricably linked with the node it runs on ? I guess it is possible that term Node Affinity could be used instead of Instance Affinity for those cluster resources eg SCAN Listener etc that are part of the cluster but not strictly part of the Database Instance ?
Q5. Resource affinity - I wasn't quite sure if this meant a Resource having an affinity to a node or something having an Affinity to a particular Resource ?
Any clarity greatly appreciated,
thanks - Jim