Port 9200 / TCP
Elasticsearch REST API
Port 9200 – Elasticsearch REST API Protocol Specification
Technical analysis, security advisories, vulnerability mitigation, and firewall syntax for TCP/UDP port 9200 (Elasticsearch REST API).
Port Number
9200
Transport Protocol
TCP
Port Range Type
Registered (1024-49151)
Default Status
Restricted / LAN
Service Description & Architectural Context
Elasticsearch HTTP search and analytics engine REST interface.
IANA / RFC Designation:
Port 9200 is assigned to Elasticsearch REST API under the Internet Assigned Numbers Authority (IANA) service name registry. In enterprise infrastructure and homelab setups, services listening on this port must follow the principle of least privilege.
Security Analysis & Attack Surface Assessment
Enable Elastic Security (TLS, role-based access) to prevent ransomware.
Hardening Recommendations:
- Do not expose port 9200 to public WAN interfaces unless authenticated TLS or VPN wrapping is strictly enforced.
- Enforce rate-limiting using Fail2ban, CrowdSec, or cloud edge DDoS protection.
- Audit active listening sockets locally:
ss -tulpn | grep :9200ornetstat -ano | findstr :9200.
Firewall Rule Snippets for Port 9200
UFW (Ubuntu / Debian Linux)
sudo ufw allow 9200/tcp
iptables (Standard Linux Kernel)
sudo iptables -A INPUT -p tcp --dport 9200 -j ACCEPT
Windows PowerShell (Defender Advanced Firewall)
New-NetFirewallRule -DisplayName "Allow Port 9200" -Direction Inbound -LocalPort 9200 -Protocol TCP -Action Allow