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Port 2439 (sybasedbsynch)

IANA assigns port 2439 to sybasedbsynch: SybaseDBSynch.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
sybasedbsynch TCP SybaseDBSynch Dave Neudoerffer -
sybasedbsynch UDP SybaseDBSynch Dave Neudoerffer -

Check what is listening on port 2439

Linux: is anything listening on TCP 2439?
sudo ss -tlnp 'sport = :2439'
Linux: UDP 2439
sudo ss -ulnp 'sport = :2439'
Linux / macOS: which process owns the port
sudo lsof -nP -i :2439
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':2439 '
Windows (Command Prompt)
netstat -ano | findstr :2439
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 2439 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 2439
From Windows
Test-NetConnection HOST -Port 2439
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 2439

Block port 2439 in the firewall

ufw
sudo ufw deny 2439/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 2439 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 2439 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 2439' -Direction Inbound -Protocol TCP -LocalPort 2439 -Action Block
ufw
sudo ufw deny 2439/udp
iptables
sudo iptables -A INPUT -p udp --dport 2439 -j DROP
nftables
sudo nft add rule inet filter input udp dport 2439 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 2439' -Direction Inbound -Protocol UDP -LocalPort 2439 -Action Block

Related ports

2437unicontrol2438msp2440spearway2441pvsw-inet

All port numbers · Open port checker
Assignment data: IANA port number registry (public domain), retrieved 2026-11-10.