如何使用 LDAP 为 ORACLE 设置 C# 连接字符串以指定数据库？

Question

I have a connection string to a Oracle database that looks like this:

Data Source=myserver:1521/myservice;User ID=MY_SCHEMA;Password=mypassword

I understand this is basically a TNS-less way of specifying the database we are connecting too. It works, but normally we refer our databases as they are specified in LDAP. Especially useful if a database is moved to a new location, we only have to update the LDAP entry. I've tried it like this:

Data Source=MYLDAPENTRY;User ID=MY_SCHEMA;Password=mypassword

However, when I try to connect this way I get an

ORA-12154: TNS:could not resolve the connect identifier specified

A TNSPING of MYLDAPENTRY gives me back

Used LDAP adapter to resolve the alias
Attempting to contact (DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=myserver)(PORT=1521)))
(CONNECT_DATA=(SERVICE_NAME=myservice)))
OK (140 msec)

Which matches the TNS-less connection I'm able to get working.

Connecting with SQLPLUS on the same server/workstation works fine:

sqlplus MY_SCHEMA/mypassword@MYLDAPENTRY 

I would expect given the error, it's defaulting to searching TNSNames.ora instead of consulting LDAP.ora and querying the indicated LDAP server

Is there a different way to specify it when dealing with an LDAP server; or something I have to configure in OPT.NET?

Answer 1

This gave me a clue... https://stackoverflow.com/a/41571809/685

I am using the ODP.Net Managed Driver. It won't read the TNS_ADMIN environment variable nor the equivalent registry key. So you have two options to resolve this:

[1] You can specify the TNS_ADMIN value in one of your .config files (e,g, app.config, web.config, and machine.config)

<oracle.manageddataaccess.client>
    <version number="*">
        <settings>
            <setting name="TNS_ADMIN" value="C:\oracle\work"/>
        </settings>
    </version>
</oracle.manageddataaccess.client>

Your mileage may vary depending on where the Oracle client is installed on your server or workstation (I know the path can vary depending on the version installed in my shop)

Or

[2] You can specify the location of the LDAP server directly.

<oracle.manageddataaccess.client>
    <version number="*">
        <LDAPsettings>
            <LDAPsetting name="DIRECTORY_TYPE" value="AD" />
            <LDAPsetting name="DEFAULT_ADMIN_CONTEXT" value="DC=ad,DC=myDomain,DC=myTLD"/>
            <LDAPsetting name="DIRECTORY_SERVERS" value="(ad.myDomain.myTLD:PORTNUMBER)"/>
            <LDAPsetting name="DIRECTORY_SERVER_TYPE" value="AD"/>
        </LDAPsettings>
        <settings>
            <setting name="NAMES.DIRECTORY_PATH" value="(LDAP)"/>
            <setting name="NAMES.DEFAULT_DOMAIN" value="ad.myDomain.myTLD"/>
        </settings>
    </version>
</oracle.manageddataaccess.client>

In my case this is a LOT less likely to change between servers/workstations or over time as servers are replaced.