CentOS Linux 7.5
Oracle Database XE 18c
ORDS 18.3
APEX 18.2
My ORDS instance works perfectly fine if I use `basic` type of connection in my `defaults.xml`:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd">
<properties>
<entry key="db.connectionType">basic</entry>
<entry key="db.hostname">localhost</entry>
<entry key="db.port">1521</entry>
<entry key="db.servicename">XEPDB1</entry>
<entry key="security.requestValidationFunction">wwv_flow_epg_include_modules.authorize</entry>
<entry key="security.validationFunctionType">plsql</entry>
</properties>
However, if I change the connection type property to `tns` like this:
<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd">
<properties>
<entry key="db.connectionType">tns</entry>
<entry key="db.tnsDirectory">/opt/oracle/product/18c/dbhomeXE/network/admin</entry>
<entry key="db.tnsAliasName">pdb1</entry>
<entry key="security.requestValidationFunction">wwv_flow_epg_include_modules.authorize</entry>
<entry key="security.validationFunctionType">plsql</entry>
</properties>
And my tnsnames.ora looks as following:
# tnsnames.ora Network Configuration File: /opt/oracle/product/18c/dbhomeXE/network/admin/tnsnames.ora
# Generated by Oracle configuration tools.
XE =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
(CONNECT\_DATA =
(SERVER = DEDICATED)
(SERVICE\_NAME = XE)
)
)
PDB1 =
(DESCRIPTION =
(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
(CONNECT\_DATA =
(SERVER = DEDICATED)
(SERVICE\_NAME = XEPDB1)
)
)
LISTENER_XE =
(ADDRESS = (PROTOCOL = TCP)(HOST = localhost)(PORT = 1521))
ORDS won't resolve the descriptor and generates this exception:
IO Error: could not resolve the connect identifier "pdb1"
In my browser window:

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Is there anything I am doing wrong or is it a known ORDS issue?
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P.S. My tnsnames entry works fine in other places, in example with sqlplus:
# sqlplus sys@pdb1 as sysdba
SQL*Plus: Release 18.0.0.0.0 - Production on Tue Nov 20 00:01:06 2018
Version 18.4.0.0.0
Copyright (c) 1982, 2018, Oracle. All rights reserved.
Enter password:
Connected to:
Oracle Database 18c Express Edition Release 18.0.0.0.0 - Production
Version 18.4.0.0.0
SQL>