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Port 153 (sgmp)

IANA assigns port 153 to sgmp: SGMP.

Well-known (system) port, 0-1023 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
sgmp TCP SGMP Marty Schoffstahl -
sgmp UDP SGMP Marty Schoffstahl -

Check what is listening on port 153

Linux: is anything listening on TCP 153?
sudo ss -tlnp 'sport = :153'
Linux: UDP 153
sudo ss -ulnp 'sport = :153'
Linux / macOS: which process owns the port
sudo lsof -nP -i :153
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':153 '
Windows (Command Prompt)
netstat -ano | findstr :153
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 153 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 153
From Windows
Test-NetConnection HOST -Port 153
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 153

Block port 153 in the firewall

ufw
sudo ufw deny 153/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 153 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 153 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 153' -Direction Inbound -Protocol TCP -LocalPort 153 -Action Block
ufw
sudo ufw deny 153/udp
iptables
sudo iptables -A INPUT -p udp --dport 153 -j DROP
nftables
sudo nft add rule inet filter input udp dport 153 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 153' -Direction Inbound -Protocol UDP -LocalPort 153 -Action Block

Related ports

151hems152bftp154netsc-prod155netsc-dev

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