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Port 383 (hp-alarm-mgr)

IANA assigns port 383 to hp-alarm-mgr: hp performance data alarm manager.

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

IANA assignment

Service nameProtoDescriptionAssigneeReference
hp-alarm-mgr TCP hp performance data alarm manager Frank Blakely -
hp-alarm-mgr UDP hp performance data alarm manager Frank Blakely -

Check what is listening on port 383

Linux: is anything listening on TCP 383?
sudo ss -tlnp 'sport = :383'
Linux: UDP 383
sudo ss -ulnp 'sport = :383'
Linux / macOS: which process owns the port
sudo lsof -nP -i :383
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':383 '
Windows (Command Prompt)
netstat -ano | findstr :383
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 383 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 383
From Windows
Test-NetConnection HOST -Port 383
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 383

Block port 383 in the firewall

ufw
sudo ufw deny 383/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 383 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 383 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 383' -Direction Inbound -Protocol TCP -LocalPort 383 -Action Block
ufw
sudo ufw deny 383/udp
iptables
sudo iptables -A INPUT -p udp --dport 383 -j DROP
nftables
sudo nft add rule inet filter input udp dport 383 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 383' -Direction Inbound -Protocol UDP -LocalPort 383 -Action Block

Related ports

381hp-collector382hp-managed-node384arns385ibm-app

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