Port 4851

derby-repli · TCP/UDP

RangeRegistered port (1024–49151)
ProtocolTCP/UDP
Servicederby-repli
Registered2008-02-27

Frequently asked questions

What is port 4851 used for?

Port 4851 is registered with the IANA for derby-repli (TCP/UDP). Description: Apache Derby Replication.

Is port 4851 a well-known port?

No. Port 4851 is in the range 1024–49151 (registered or user ports). Ordinary programs may open it without root privileges.

How do I check whether port 4851 is open?

Locally on Linux with ss -tulpn | grep ':4851\b', on Windows with netstat -ano | findstr :4851. To test a remote host use Test-NetConnection <host> -Port 4851 in PowerShell or nc -zv <host> 4851 on Linux/macOS.

How do I open port 4851 in the firewall?

Ubuntu/Debian (ufw): sudo ufw allow 4851/tcp. Fedora/RHEL (firewalld): sudo firewall-cmd --add-port=4851/tcp --permanent, then firewall-cmd --reload. Windows (PowerShell as administrator): New-NetFirewallRule -DisplayName "Port 4851" -Direction Inbound -Protocol TCP -LocalPort 4851 -Action Allow.

IANA registry entries

ProtocolServiceDescription (IANA)
TCPderby-repliApache Derby Replication
UDPderby-repliApache Derby Replication

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