HTTPfy

Port 2657 (sns-dispatcher)

IANA assigns port 2657 to sns-dispatcher: SNS Dispatcher.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
sns-dispatcher TCP SNS Dispatcher - -
sns-dispatcher UDP SNS Dispatcher - -

Check what is listening on port 2657

Linux: is anything listening on TCP 2657?
sudo ss -tlnp 'sport = :2657'
Linux: UDP 2657
sudo ss -ulnp 'sport = :2657'
Linux / macOS: which process owns the port
sudo lsof -nP -i :2657
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':2657 '
Windows (Command Prompt)
netstat -ano | findstr :2657
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 2657 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 2657
From Windows
Test-NetConnection HOST -Port 2657
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 2657

Block port 2657 in the firewall

ufw
sudo ufw deny 2657/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 2657 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 2657 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 2657' -Direction Inbound -Protocol TCP -LocalPort 2657 -Action Block
ufw
sudo ufw deny 2657/udp
iptables
sudo iptables -A INPUT -p udp --dport 2657 -j DROP
nftables
sudo nft add rule inet filter input udp dport 2657 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 2657' -Direction Inbound -Protocol UDP -LocalPort 2657 -Action Block

Related ports

2655unglue2656kana2658sns-admin2659sns-query

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