Oracle Network Configuration

Welcome to Oracle Network Configuration Management, the second in a two-course series introducing the networking tools and concepts built into Oracle's database software. Oracle Network Topology, the first course in this series, covers the general concepts behind:

1. Oracle networking
2. Oracle Net Services architecture
3. Client- and server-side configuration

This course, Network Configuration Management, goes deeper into actually configuring and using Oracle Net Services components, including:

1. Directory naming through Oracle Internet Directory and LDAP (the older Oracle Names service, also known as Oracle Names Server or ONAMES, was retired long ago in favor of Oracle Directory Naming)
2. Oracle Enterprise Manager Cloud Control and Oracle Net Manager, the two current tools for managing Net Services configuration
3. Oracle Shared Server
4. Oracle Connection Manager

This course also covers security and troubleshooting in the network environment.

After completing this course, you'll be able to:

1. Describe how directory naming works through Oracle Internet Directory and LDAP
2. Use Oracle Net Manager, and Oracle Enterprise Manager Cloud Control, to configure centralized naming
3. Store and manage your overall network topology
4. Explain why applications relying on an old-style Names Server for connect string resolution need to migrate to LDAP directory naming through Oracle Internet Directory instead
5. Configure Oracle Shared Server
6. Describe the features of Oracle Connection Manager, including its REST interface for administration
7. Use logging and tracing to troubleshoot the Oracle Net environment
8. Identify network security risks during data transmission
9. Identify the features of Oracle Advanced Security, a separately licensable product covering network encryption and related security capabilities

If you've already taken the first course in this series, some of this material will already be familiar. The next lesson outlines the prerequisites for this course.

Oracle Net Services, originally introduced as SQL*Net, is a core, inseparable part of the Oracle Database software stack, not a separately installed add-on. That's just as true in 26ai as it was in 11g R2 and every version in between. Where connectivity has genuinely moved on since the SQL*Net era is in how clients actually reach a database: modern applications increasingly connect through Easy Connect Plus and OCI-native connection methods rather than hand-building a classic tnsnames.ora-based setup for every client.

A few of the lower-level pieces worth knowing about before this course goes further:

• TCP/IP remains the primary transport protocol Oracle Net Services runs on top of, whether the database is on-premises or running in Oracle Cloud Infrastructure.
• TNS (Transparent Network Substrate) is Oracle's own abstraction layer that lets a client find and connect to a database without the application needing to know the specifics of the underlying transport protocol. Every time you use a TNS alias from a tnsnames.ora file, or an Easy Connect string, you're using TNS. This is still exactly as central to Oracle connectivity in 26ai as it's ever been.
• OPI (Oracle Program Interface) is the layer on the database side that answers requests sent from the client's Oracle Call Interface, in effect, the client's "OCI" (Oracle Call Interface, not to be confused with Oracle Cloud Infrastructure below) sends a request, and OPI provides the response. Developers today work through higher-level APIs, JDBC, ODP.NET, python-oracledb, which sit on top of this layer rather than calling it directly. You'll mostly encounter OPI and its lower-level counterpart by name when reading trace file output during network troubleshooting, later in this course, rather than as something you configure day to day.

It's worth being precise about "OCI" here, since the acronym does double duty in Oracle material: Oracle Call Interface is the client-side C API just described, part of Net Services' own architecture. Oracle Cloud Infrastructure is Oracle's public cloud platform. They're unrelated concepts that happen to share an abbreviation, and it's worth catching that collision now rather than getting confused by it later when reading Oracle's own documentation.

Easy Connect itself isn't new, it's been the zero-configuration naming method enabled by default since long before 26ai, letting a client connect using nothing but a hostname, with no repository or configuration file required at all. What's changed is how much that simple mechanism can now do. Starting with Oracle Database 19c, an enhancement called Easy Connect Plus extended the syntax considerably: applications still don't need tnsnames.ora, sqlnet.ora, or the TNS_ADMIN environment variable configured, but the connect string itself can now carry protocol selection (including TCPS, not just plain TCP, which matters for cloud services that require encrypted connections), multiple hosts or ports for load balancing, and a full set of name-value parameters, failover, load balancing, buffer sizes, retry counts, and TLS security attributes, appended directly to the connection string with ?parameter=value syntax.

26ai adds one more piece worth knowing specifically: you can now specify one or more address lists of protocol addresses that share common characteristics, directly within an Easy Connect Plus string, rather than needing a full tnsnames.ora entry to express that same grouping. For a lot of common connectivity scenarios, that's a meaningful reduction in what a client needs configured locally at all, which is exactly the kind of networking-layer change worth calling out in a course built around the Oracle Net Services architecture, rather than treating Easy Connect as a minor convenience feature.

Whatever naming method you use, adopting a predictable naming and distribution strategy for your connect identifiers pays off the first time something breaks. The TNSPING utility is the standard first step in that troubleshooting flow: it determines whether the listener for a given service can actually be reached, and if it succeeds, it reports the round-trip time in milliseconds it took to reach that listener.

tnsping net_service_name count

Here, net_service_name has to exist in your tnsnames.ora file, or whatever naming method is actually in use, and count, optional, controls how many times it tries. One nuance worth remembering before you trust the result too much: a successful TNSPING only confirms the listener is reachable, it does not confirm the database itself is actually up. For that, you still need an actual connection attempt through SQL*Plus or an application.

On the cloud side specifically: Oracle Cloud Infrastructure doesn't replace Oracle Net Services, it provides the network, compute, and storage that an Oracle AI Database instance runs on. Whether an application connects to a database on-premises, in OCI, or in another cloud entirely, Oracle Net Services is still the mechanism doing the actual connecting. OCI's own network features, virtual cloud networks, security lists, load balancers, work alongside Net Services rather than instead of it.

What might once have felt like a separate "networking branch" in older on-premises deployments was really just the distinct configuration and management of components like the listener and Connection Manager. Both are still very much part of Oracle Net Services today, and Connection Manager specifically has kept gaining capability: in current Oracle AI Database releases it has a REST interface (CMCTL's REST API) for administration, alongside its long-standing Traffic Director Mode for connection routing and pooling.

In short, Oracle Net Services is still the connective tissue underneath every Oracle Database connection. It has always been deeply integrated into the database software, and 26ai doesn't change that; it just gives you more ways, and better tooling, to manage it.

That's the shape the rest of this course follows: not a rewrite of the fundamentals from the first course in this series, but a deeper, more practical look at the specific components, directory naming, the administration tools, Shared Server, Connection Manager, security, and troubleshooting, that turn "Oracle Net Services exists" into "you can actually configure and operate it." The next lesson covers what you'll need in place before getting started.