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Port 13721 (bpdbm)

IANA assigns port 13721 to bpdbm: BPDBM Protocol (VERITAS NetBackup).

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
bpdbm TCP BPDBM Protocol (VERITAS NetBackup) Jeff Holmbeck -
bpdbm UDP BPDBM Protocol (VERITAS NetBackup) Jeff Holmbeck -

Check what is listening on port 13721

Linux: is anything listening on TCP 13721?
sudo ss -tlnp 'sport = :13721'
Linux: UDP 13721
sudo ss -ulnp 'sport = :13721'
Linux / macOS: which process owns the port
sudo lsof -nP -i :13721
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':13721 '
Windows (Command Prompt)
netstat -ano | findstr :13721
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 13721 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 13721
From Windows
Test-NetConnection HOST -Port 13721
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 13721

Block port 13721 in the firewall

ufw
sudo ufw deny 13721/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 13721 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 13721 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 13721' -Direction Inbound -Protocol TCP -LocalPort 13721 -Action Block
ufw
sudo ufw deny 13721/udp
iptables
sudo iptables -A INPUT -p udp --dport 13721 -j DROP
nftables
sudo nft add rule inet filter input udp dport 13721 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 13721' -Direction Inbound -Protocol UDP -LocalPort 13721 -Action Block

Related ports

13400doip-data, doip-disc13720bprd13722bpjava-msvc13724vnetd

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