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Port 4601 (piranha2)

IANA assigns port 4601 to piranha2: Piranha2.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
piranha2 TCP Piranha2 Primark Corporation -
piranha2 UDP Piranha2 Primark Corporation -

Check what is listening on port 4601

Linux: is anything listening on TCP 4601?
sudo ss -tlnp 'sport = :4601'
Linux: UDP 4601
sudo ss -ulnp 'sport = :4601'
Linux / macOS: which process owns the port
sudo lsof -nP -i :4601
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':4601 '
Windows (Command Prompt)
netstat -ano | findstr :4601
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 4601 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 4601
From Windows
Test-NetConnection HOST -Port 4601
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 4601

Block port 4601 in the firewall

ufw
sudo ufw deny 4601/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 4601 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 4601 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 4601' -Direction Inbound -Protocol TCP -LocalPort 4601 -Action Block
ufw
sudo ufw deny 4601/udp
iptables
sudo iptables -A INPUT -p udp --dport 4601 -j DROP
nftables
sudo nft add rule inet filter input udp dport 4601 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 4601' -Direction Inbound -Protocol UDP -LocalPort 4601 -Action Block

Related ports

4599a17-an-an4600piranha14602mtsserver4603menandmice-upg

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