Cannot listen on public address

Question

Hello,
I'm setting a Oracle Database inside an Amazon EC2 instance and I want it to be accessible from the outside. However, when I'm starting the listener, I've got this error :
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=TCP)(HOST=test-db)(PORT=1521)))
TNS-12543: TNS:destination host unreachable
TNS-12560: TNS:protocol adapter error
TNS-00513: Destination host unreachable
Linux Error: 113: No route to host
In my hosts file, I've added this line to correctly resolve the "test-db" host (x.x.x.x is the public IP of my EC2 instance). Pinging "test-db" does work properly
x.x.x.x test-db.fic-test-lab.com test-db
And finally, my listener.ora file looks like this:
LISTENER =
(DESCRIPTION_LIST =
(DESCRIPTION =
(ADDRESS_LIST =
(ADDRESS = (PROTOCOL = TCP)(HOST = test-db)(PORT = 1521))
SID_LIST_LISTENER=
(SID_LIST=
(SID_DESC=
(GLOBAL_DBNAME=orcl)
(ORACLE_HOME=/u01/app/oracle/product/11.2.0/dbhome_1)
(SID_NAME=orcl)
If I change "test-db" to "127.0.0.1", everything works perfectly, but the database is obviously not accessible from the outside. I can't find what step I'm missing...
Thanks,
jtellier

Answer 1

damorgan - I'm simply trying to set up a database that would be publicly accessible. The database version is 11gR2.
It was my understanding that if the address specified in listener.ora was 127.0.0.1, the listener would only accept connections from localhost, not from the outside. And that's what seems to be happening for me.
Pradeepan - When starting the listener without any listener.ora, I've got this error:
Listening on: (DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=test-db.fic-test-lab.com)(PORT=1521)))
Connecting to (ADDRESS=(PROTOCOL=tcp)(HOST=)(PORT=1521))
TNS-12543: TNS:destination host unreachable
TNS-12560: TNS:protocol adapter error
TNS-00513: Destination host unreachable
Linux Error: 113: No route to host
sb92075 - Yes, it would make sense... ifconfig shows that eth0 has a 10. address and it doesn't show any interface with the public address. After reading the page posted by jgarry regarding EC2 instances addressing, I understand that the public IP is only used by NAT and is not known by the OS. So yeah, the cause seems to be the OS...
jgarry - Yes, it's the same address.
So now, if I understand the problem correctly with the additional info in the page posted by jgarry, the problem is that I can't put the public address in my listener.ora file because the OS doesn't know about this address. On the other hand, if the listener listen on localhost, it wont accept connections from the outside. Does that make sense?
Thanks,
--jtellier