HTTPfy

Port 1817 (rkb-oscs)

IANA assigns port 1817 to rkb-oscs: RKB-OSCS.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
rkb-oscs TCP RKB-OSCS Robert Kevin Breton -
rkb-oscs UDP RKB-OSCS Robert Kevin Breton -

Check what is listening on port 1817

Linux: is anything listening on TCP 1817?
sudo ss -tlnp 'sport = :1817'
Linux: UDP 1817
sudo ss -ulnp 'sport = :1817'
Linux / macOS: which process owns the port
sudo lsof -nP -i :1817
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':1817 '
Windows (Command Prompt)
netstat -ano | findstr :1817
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 1817 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 1817
From Windows
Test-NetConnection HOST -Port 1817
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 1817

Block port 1817 in the firewall

ufw
sudo ufw deny 1817/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 1817 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 1817 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 1817' -Direction Inbound -Protocol TCP -LocalPort 1817 -Action Block
ufw
sudo ufw deny 1817/udp
iptables
sudo iptables -A INPUT -p udp --dport 1817 -j DROP
nftables
sudo nft add rule inet filter input udp dport 1817 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 1817' -Direction Inbound -Protocol UDP -LocalPort 1817 -Action Block

Related ports

1815mmpft1816harp1818etftp1819plato-lm

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