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Port 3911 (prnstatus)

IANA assigns port 3911 to prnstatus: Printer Status Port.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
prnstatus TCP Printer Status Port Brett Green -
prnstatus UDP Printer Status Port Brett Green -

Registry dates for this port: registered 2003-11.

Check what is listening on port 3911

Linux: is anything listening on TCP 3911?
sudo ss -tlnp 'sport = :3911'
Linux: UDP 3911
sudo ss -ulnp 'sport = :3911'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3911
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3911 '
Windows (Command Prompt)
netstat -ano | findstr :3911
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3911 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3911
From Windows
Test-NetConnection HOST -Port 3911
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3911

Block port 3911 in the firewall

ufw
sudo ufw deny 3911/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3911 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3911 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3911' -Direction Inbound -Protocol TCP -LocalPort 3911 -Action Block
ufw
sudo ufw deny 3911/udp
iptables
sudo iptables -A INPUT -p udp --dport 3911 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3911 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3911' -Direction Inbound -Protocol UDP -LocalPort 3911 -Action Block

Related ports

3909surfcontrolcpa3910prnrequest3912gbmt-stars3913listcrt-port

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