PORT 8123 / TCPDatabase & CacheExposure Risk: High

Port 8123: ClickHouse HTTP / Home Assistant — ClickHouse OLAP HTTP SQL Interface & Home Assistant

Default HTTP query interface for ClickHouse analytical databases and Home Assistant dashboards.

Default Service

ClickHouse HTTP / Home Assistant

Process: clickhouse-server

Transport Protocol

TCP

IANA Registered Port 8123

Docker Port Flag

-p 8123:8123

Container to Host Mapping

How to Check & Kill Process on Port 8123 (EADDRINUSE Fix)

macOS & Linux (lsof / kill)

# Find process using port 8123
sudo lsof -i :8123

# Instantly kill process on port 8123
lsof -ti:8123 | xargs kill -9

Windows (PowerShell & CMD)

# Find PID listening on port 8123
netstat -ano | findstr :8123

# Force kill by PID
taskkill /PID <PID_NUMBER> /F

Cross-Platform Node.js One-Liner

# Kill port 8123 via npx
npx kill-port 8123

# Or diagnose via Castov CLI
npx castov fix "EADDRINUSE :::8123"

Linux Firewall (UFW) & Connectivity Test

# Test if port 8123 is reachable
nc -zv localhost 8123

# Allow or deny port 8123 in UFW
sudo ufw allow 8123/tcp

CLOUD & INFRASTRUCTURE PARTNER2 Slots Open

Deploying High-Availability Cloud Servers, VPCs, or Managed Databases?

Reach backend engineers and SREs actively debugging ports, CIDR subnets, and production infrastructure.

Try Team Env Vault Sponsor Castov

Frequently Asked Questions about Port 8123

What is Port 8123 used for?

Port 8123 is the standard network port for ClickHouse HTTP / Home Assistant (ClickHouse OLAP HTTP SQL Interface & Home Assistant) operating over TCP. The typical system daemon or process is clickhouse-server.

How do I kill a process running on Port 8123 (EADDRINUSE)?

On macOS and Linux, run: lsof -ti:8123 | xargs kill -9 (or npx kill-port 8123). On Windows PowerShell/CMD, run: netstat -ano | findstr :8123 and then taskkill /PID <PID> /F.