Which two statements about the Single Client Access Name (SCAN) feature are correct?
A.
In typical Grid Infrastructure Installation, the SCAN name defaults to the cluster name
B.
A SCAN listener runs on every cluster node
C.
SCAN is available with any version of Oracle 11g RAC
D.
SCAN provides location Independence of Oracle RAC databases in the cluster
Explanation:
SCAN components in a cluster:
SCAN Name will represent the cluster in the network. SCAN Name needs to be registered in DNS
and resolved using round-robin algorithm. To test the round-robin algorithm, perform nslookup on
the SCAN Name. The DNS server should return those 3 set of IP Address in different order each
time
Incorrect:
Not C: Only from R2:
Prior to Oracle 11g R1 RAC, client connection to RAC Cluster will use each node VIP (virtual IP)
address. So each time a node is added to the cluster, the client tnsnames.ora file needs to be
updated with the new VIP addition.Oracle 11g R2 RAC introduces SCAN (Single Client Access Name) to handle that problem. SCAN
provides single name from clients to access the database running in the cluster.
Correct is B,D
My mistake. Correct is A,D.
By default Oracle runs only 3 SCAN listeners unless you add more.