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Port 5456 (apc-5456)

IANA assigns port 5456 to apc-5456: APC 5456.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
apc-5456 TCP APC 5456 American Power Conve -
apc-5456 UDP APC 5456 American Power Conve -

Check what is listening on port 5456

Linux: is anything listening on TCP 5456?
sudo ss -tlnp 'sport = :5456'
Linux: UDP 5456
sudo ss -ulnp 'sport = :5456'
Linux / macOS: which process owns the port
sudo lsof -nP -i :5456
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':5456 '
Windows (Command Prompt)
netstat -ano | findstr :5456
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 5456 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 5456
From Windows
Test-NetConnection HOST -Port 5456
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 5456

Block port 5456 in the firewall

ufw
sudo ufw deny 5456/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 5456 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 5456 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 5456' -Direction Inbound -Protocol TCP -LocalPort 5456 -Action Block
ufw
sudo ufw deny 5456/udp
iptables
sudo iptables -A INPUT -p udp --dport 5456 -j DROP
nftables
sudo nft add rule inet filter input udp dport 5456 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 5456' -Direction Inbound -Protocol UDP -LocalPort 5456 -Action Block

Related ports

5454apc-54545455apc-54555461silkmeter5462ttl-publisher

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