Port 3019: Resource Manager — Registered, Forgotten

What Port 3019 Is

Port 3019 sits in the registered port range (1024–49151), the middle tier of the port number system. IANA lists it as resource-mgr on both TCP and UDP, registered by someone named Gary Glover for a service called Resource Manager.¹

That registration exists. The service does not — at least not in any documented, maintained, or publicly traceable form. No RFC. No specification. No software that identifies itself by this name on this port. Whatever Resource Manager was, it has left no footprint beyond the registry entry itself.

In practice, port 3019 behaves as unassigned.

The Registered Port Range

Ports 1024–49151 are the registered range. Unlike well-known ports (0–1023), you don't need root or administrator privileges to open them. IANA maintains a registry of assignments in this range, but the registry is not enforced — any application can bind to any port, registered or not.

The registry is a coordination mechanism, not a technical constraint. Registration means "we asked IANA to note that we use this port." It means nothing about whether the software still exists, whether anyone else respects the reservation, or whether the port is actually in use anywhere.

Port 3019 illustrates this gap. It's claimed on paper. It's open in practice.

What You'll Actually Find on Port 3019

Because the official assignment is defunct, port 3019 is fair game for any application that needs a port and happens to pick this one. Development servers, internal tools, games, and custom services all occasionally land here.

If you see port 3019 active on a machine you manage, it was put there by something local — not by any standard protocol.

How to Check What's Listening

Linux / macOS:

# Show which process is using port 3019
ss -tlnp | grep 3019

# Or with lsof
lsof -i :3019

Windows:

netstat -ano | findstr :3019

The process ID in the output can be matched against Task Manager or tasklist to identify the application.

Why Ghost Registrations Exist

The IANA port registry accumulated tens of thousands of entries over decades. Some registrations came from thriving software ecosystems. Others came from individual developers, internal tools, and products that never shipped widely or quietly went away. IANA doesn't remove entries when software dies — the registry grows, but it doesn't prune.

The result is a registry full of ghost registrations: ports with names attached to services that no longer exist. Port 3019 is one of them. The name resource-mgr sits in the official record, pointing at nothing.

It's a small archaeology lesson. Someone once built something, cared enough to register a port for it, and then it was gone.