HTTPfy

Port 3254 (pda-sys)

IANA assigns port 3254 to pda-sys: PDA System.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
pda-sys TCP PDA System Jian Fan -
pda-sys UDP PDA System Jian Fan -

Registry dates for this port: registered 2002-02.

Check what is listening on port 3254

Linux: is anything listening on TCP 3254?
sudo ss -tlnp 'sport = :3254'
Linux: UDP 3254
sudo ss -ulnp 'sport = :3254'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3254
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3254 '
Windows (Command Prompt)
netstat -ano | findstr :3254
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3254 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3254
From Windows
Test-NetConnection HOST -Port 3254
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3254

Block port 3254 in the firewall

ufw
sudo ufw deny 3254/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3254 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3254 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3254' -Direction Inbound -Protocol TCP -LocalPort 3254 -Action Block
ufw
sudo ufw deny 3254/udp
iptables
sudo iptables -A INPUT -p udp --dport 3254 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3254 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3254' -Direction Inbound -Protocol UDP -LocalPort 3254 -Action Block

Related ports

3252dhe3253pda-data3255semaphore3256cpqrpm-agent

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