What Port 3002 Is
Port 3002 sits in the registered port range (1024–49151), the middle tier of the port number system. IANA formally assigned it to a service called EXLM Agent — an obscure enterprise application that left almost no trace on the modern Internet. The registration exists; the service, for practical purposes, does not.
In practice, this port belongs to two entirely different communities: developers running local servers, and a handful of enterprise telephony deployments using Miralix CSTA.
The Registered Service: EXLM Agent
IANA lists port 3002 (TCP and UDP) under the service name exlm-agent.1 Beyond the registration itself, documentation on what EXLM Agent actually was is sparse. This is not unusual: the registered port range accumulated many assignments over the decades, some from products that never achieved wide adoption, some from companies that no longer exist.
The registration means the port is technically "claimed" — other software is supposed to avoid it for default configurations. In practice, that constraint is largely ignored.
Unofficial Uses
Miralix CSTA
Miralix, an enterprise telephony software vendor, uses port 3002 for its CSTA (Computer Supported Telecommunications Applications) implementation.2 CSTA is a protocol standard for integrating computers with phone systems — the kind of plumbing that lets call center software see who's calling, initiate transfers, and log events. Miralix's use here is unofficial (not registered with IANA), layered on top of the existing EXLM assignment.
Development Server Overflow
More commonly than either of the above: port 3002 is where the third local development server lands.
Port 3000 is the default for React (Create React App), Next.js, and many Node.js frameworks. When 3000 is taken, servers often move to 3001. When 3001 is taken — or when you're running a frontend, a backend, and a mock API simultaneously — 3002 is the natural next stop.3 This happens millions of times a day on developer laptops. No specification requires it; it's just what the numbers suggest.
Elastic App Search has also used port 3002 as a default in certain configurations.4
How to Check What's Listening
If you see traffic on port 3002 and aren't sure what's using it:
macOS / Linux:
Linux (alternative):
Windows:
These commands show the process name and PID, which is usually enough to identify the owner.
Why Unassigned and Lightly-Used Ports Matter
The registered port range exists to reduce collisions. If every application chose a random port, two pieces of software would regularly conflict by default. The registration system — imperfect as it is — gives applications a way to claim a port number as their own, making default configurations more predictable.
Port 3002's situation (nominal registration, forgotten service, colonized by convention) is common. The registered range has thousands of ports in similar states: officially claimed, practically available. The result is a system where the rules and the reality don't quite match, but things generally work anyway — because developers, like packets, find the open path.
بۇ بەت پايدىلىق بولدىمۇ؟