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TNS-12547: TNS:lost contact

AlbertoFaenzaApr 15 2017 — edited Apr 17 2017

Hi,

for a test I have installed in a Virtualbox machine Oracle Linux 7 and Oracle Database 12.2.0.1.

Installation was fine and within the virtual machine everything is working (listener, DBs).

I have created a container DB (CDB01) and a pluggable DB (PDB01).

Connecting with sqlplus  within the virtual machine works with no issues.

I have forwarded in Virtualbox port 1521 from host to guest (host port 1521, guest port 1521).

If I try to tnsping from Windows 10 (Virtualbox host) with Oracle client 12.2.0.1. I got the following error:

C:\> tnsping pdb01

TNS Ping Utility for 64-bit Windows: Version 12.2.0.1.0 - Production on 15-APR-2017 15:06:53

Copyright (c) 1997, 2016, Oracle.  All rights reserved.

Used parameter files:

C:\ProgramData\Oracle\product\12.2.0\client_1\network\admin\sqlnet.ora

Used TNSNAMES adapter to resolve the alias

Attempting to contact (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))) (CONNECT_DATA = (SERVER = DEDICATED) (SERVICE_NAME = PDB01)))

TNS-12547: TNS:lost contact

If I try to telnet from Windows host with the command:

C:\> telnet localhost 1521

I got no specific error and after a while the telnet will exit.

sqlnet.ora on windows is pretty simple:

SQLNET.AUTHENTICATION_SERVICES= (NTS)

NAMES.DIRECTORY_PATH= (TNSNAMES, EZCONNECT)

I have googled a bit but could not find how to troubleshoot this issue.

Please note that this problem happens only with remote connections. When connecting within Oracle Linux both tnsping and sqlplus works smoothly.

Do you have any suggestion to investigate this issue? Is there any log that provides additional information on the cause of this problem?

Regards,

Alberto

This post has been answered by Dude! on Apr 16 2017
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