Scan listener is NOT starting up

Question

Hi,
I have installed 11gR2 two node RAC on OEL5.2, 64 bit.
When ever I start the node, in one of the node SCAN listener will NOT be running.
If I start the node one first then scan listener will run on node, if I start second node first then scan will run on second node.
How many scan listener should run ( on both the nodes or only one nodes ) ??? Is it okay with one SCAN listener ???
My /erc/hosts entry... I have configured ONLY one scan IP.
===================================================
[oracle@rac1 sampleXMLs]$ cat /etc/hosts
# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1 localhost.localdomain localhost
# Public Network - (eth0)
192.168.1.8 rac1.appsdba.info rac1
192.168.1.7 rac2.appsdba.info rac2
# Private Interconnect - (eth1)
192.168.0.100 rac1-priv.appsdba.info rac1-priv
192.168.0.101 rac2-priv.appsdba.info rac2-priv
# Public Virtual IP (VIP) addresses for - (eth0)
192.168.1.200 rac1-vip.appsdba.info rac1-vip
192.168.1.201 rac2-vip.appsdba.info rac2-vip
# Scan IP
192.168.1.187 racnode-cluster-scan
===================================================
Thanks.
-joy.

Answer 1

If I start the node one first then scan listener will run on node, if I start second node first then scan will run on second node.in your case ,the above result is expected.
My /erc/hosts entry... I have configured ONLY one scan IP.
192.168.1.187 racnode-cluster-scanActually this is not a way to configure the scan, please refer the below document.
normally we've 3 scan ip configured for SCAN.
http://www.oracle.com/technetwork/database/clustering/overview/scan-129069.pdf