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Port 3872 (oem-agent)

IANA assigns port 3872 to oem-agent: OEM Agent.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
oem-agent TCP OEM Agent Narain Jagathesan -
oem-agent UDP OEM Agent Narain Jagathesan -

Registry dates for this port: registered 2003-11.

Check what is listening on port 3872

Linux: is anything listening on TCP 3872?
sudo ss -tlnp 'sport = :3872'
Linux: UDP 3872
sudo ss -ulnp 'sport = :3872'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3872
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3872 '
Windows (Command Prompt)
netstat -ano | findstr :3872
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3872 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3872
From Windows
Test-NetConnection HOST -Port 3872
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3872

Block port 3872 in the firewall

ufw
sudo ufw deny 3872/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3872 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3872 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3872' -Direction Inbound -Protocol TCP -LocalPort 3872 -Action Block
ufw
sudo ufw deny 3872/udp
iptables
sudo iptables -A INPUT -p udp --dport 3872 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3872 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3872' -Direction Inbound -Protocol UDP -LocalPort 3872 -Action Block

Related ports

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