Can’t connect to Oracle 12c Release 1 in docker container from host

Ultimately, this came down to a networking issue -- configuring the guest VM's network adapter (internal switch) with a static IP (this was the hard part), assigning a hosts file entry for that IP in both the Host and the Guest machines and then altering both tnsnames.ora files (host and guest) and listner.ora (guest) to use the mapped host name.

Then everything just worked.

I've pasted my internal switch config for both the host and guest and the listener and tnsnames.ora files below.

STEPS TO CONFIGURE THE GUEST VM / HOST:

Assuming that you've already created a guest VM, with a Windows Server OS, here are the networking steps...

1. Using Hyper-V manager, use the virtual switch manager add an "Internal" type switch
2. Using Hyper-V manager, open the settings dialog for the guest VM (right click on the VM). Add a network adapter using the internal switch you just created.
3. Here are my internal switch adapter settings for the host. Note that there is a baked in assumption here that you're outside the range of IP's that would otherwise appear on your network. I know that my home network uses this range (192.168.x.x), and I know I'm ok. Also, I know that my workplace uses 10.x.x.x for wireless, so I'm good there, too.

4 . And here's how I configured the guest VM:

5 . I added hosts file aliases for the guest VM on both the host and the guest:

# internal vm's
192.168.0.120    brettvm

6 . Here's the listner.ora on the guest vm (database server):

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
      (ADDRESS = (PROTOCOL = TCP)(HOST = brettvm)(PORT = 1521))
    )
  )

ADR_BASE_LISTENER = c:\oracle

7 . Here's the tnsnames.ora on the guest VM:

LISTENER_ORCL =
  (ADDRESS = (PROTOCOL = TCP)(HOST = brettvm)(PORT = 1521))


ORCL =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = brettvm)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl)
    )
  )

8 . Finally, here's the tnsnames on the client (host machine):

LISTENER_ORCL =
  (ADDRESS = (PROTOCOL = TCP)(HOST = brettvm)(PORT = 1521))


ORCL =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = brettvm)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl)
    )
  )

Bon appetit!

--Brett

I want to propose my findings as an answer. I have tested these procedures and they seem to work fine.

NOTE: The whole experiment was done on Windows Server 2012 R2, however based on my readings I would say most of it applies to Linux too.

Shutdown

1. Shutdown the Oracle Database Instance to ensure that everything close cleanly https://docs.oracle.com/database/121/ADMQS/instance.htm#ADMQS052 http://www.dummies.com/how-to/content/how-to-stop-an-oracle-12c-database.html
2. Shutdown Windows Server

Restart

1. Start Windows Server
2. Start the Listener https://docs.oracle.com/database/121/ADMQS/network.htm#ADMQS044
3. Start the Database instance https://docs.oracle.com/database/121/ADMQS/instance.htm#ADMQS052

Remarks

Restarting the Windows Server should do everything automatically but there are a couple of remarks.

1. Starting the Oracle Services on windows is not the same as starting the database instance. However they are configured by default to behave that way. Oracle Administration Assistant for Windows can be used to determine what exactly happens with the database instance when the Oracle Services are restarted. https://docs.oracle.com/database/121/NTQRF/admin.htm#i1006074

2. Linux can also be configured to start the Oracle Database automatically using scripts. Oracle Restart was recommend in previous versions to accomplish this but is now deprecated. https://docs.oracle.com/database/121/UNXAR/strt_stp.htm#UNXAR150 http://docs.oracle.com/database/121/ADMIN/restart.htm#ADMIN12708

3. This step is no longer necessary, see below: If a pluggable database was configured during installation it should be manually started after restarting the oracle services. https://web.archive.org/web/20180911225755/http://blog.contractoracle.com:80/2013/06/oracle-12c-need-to-start-container-and.html

Do note: The 12.1.0.2 patchset introduced the ability to preserve the startup state of PDBs through a CDB restart. This is done using the ALTER PLUGGABLE DATABASE command with the OPEN and SAVE STATE options. http://oracle-base.com/articles/12c/multitenant-startup-and-shutdown-cdb-and-pdb-12cr1.php