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Port 515 (LPD / LPR)

Line Printer Daemon protocol, an old printing protocol still supported by many network printers.

Well-known (system) port, 0-1023 TCP Printing Localhost or LAN only

What port 515 is used for

Line Printer Daemon protocol, an old printing protocol still supported by many network printers.

Security: should port 515 be open?

Localhost or LAN only. LAN only; unauthenticated print jobs.

IANA assignment

Service nameProtoDescriptionAssigneeReference
printer TCP spooler - -
printer UDP spooler - -

Check what is listening on port 515

Linux: is anything listening on TCP 515?
sudo ss -tlnp 'sport = :515'
Linux / macOS: which process owns the port
sudo lsof -nP -i :515
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':515 '
Windows (Command Prompt)
netstat -ano | findstr :515
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 515 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 515
From Windows
Test-NetConnection HOST -Port 515

Block port 515 in the firewall

ufw
sudo ufw deny 515/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 515 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 515 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 515' -Direction Inbound -Protocol TCP -LocalPort 515 -Action Block

Related ports

631IPP / CUPS9100node_exporter / printer raw (JetDirect)513login, who514Syslog (UDP) / rsh (TCP)516videotex517talk

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