Port 2382: SQL Server's Directory Assistance

The registered port range

Port 2382 sits in the registered port range (1024–49151). IANA maintains this range for services that have claimed a port by registration — distinct from the well-known ports below 1024 (which require root/admin to bind) and the ephemeral ports above 49151 (assigned dynamically to outbound connections).

IANA lists 2382 as unassigned in its formal registry. In practice, Microsoft claimed it long ago.

What actually runs here

Port 2382 is used by the SQL Server Browser service as its TCP listener for SQL Server Analysis Services (SSAS) named instances.

Here's the problem it solves: SSAS default instances always listen on port 2383. But named instances — SERVER\Finance, SERVER\DWH, SERVER\PowerPivot — don't get a fixed port. They grab whatever's free when the service starts, and that number can change every time the service restarts.

So how does a client find a named instance? It asks SQL Server Browser. Browser listens on TCP port 2382, receives the named instance request, looks up the current dynamic port for that instance, and redirects the client there. Port 2382 never carries Analysis Services data directly — it carries only the redirect. ¹

Client: "I want SERVER\Finance"
Port 2382 (Browser): "That's on port 54321 today."
Client: *connects to port 54321*

This is different from Browser's other job: UDP port 1434 handles the same redirect function for the SQL Server Database Engine. Two services, two ports, same concept. ²

Power Pivot

Port 2382 appears specifically in Microsoft documentation for Power Pivot for SharePoint 2013, where the Analysis Services instance runs external to SharePoint as a named instance. Opening port 2382 in the Windows Firewall is required for Excel Services to reach it. ¹

Security

Port 2382 shows up in cloud security policies as a port that should not be open to unrestricted inbound access from the public Internet. SQL Server Browser provides instance discovery — useful inside a corporate network, unnecessary and risky when exposed publicly. ³

If you're seeing 2382 open on an Internet-facing server, that's a configuration problem worth fixing.

Check what's listening on this port

Linux/macOS:

# Show what process is bound to port 2382
sudo lsof -i :2382
sudo ss -tlnp sport = :2382

Windows:

# Show TCP listeners including PID
netstat -ano | findstr :2382

# Look up the process by PID
tasklist /fi "PID eq <pid>"

Quick probe from another machine:

# See if anything responds
nc -zv <host> 2382
nmap -p 2382 <host>

If you see sqlbrowser.exe bound to 2382 on a Windows server, that's SQL Server Browser doing its job. If you see something unexpected, that's worth investigating.

The neighbor