HTTPfy

Port 35003 (rt-devicemapper)

IANA assigns port 35003 to rt-devicemapper: ReadyTech DeviceMapper Server.

Registered (user) port, 1024-49151 TCP

IANA assignment

Service nameProtoDescriptionAssigneeReference
rt-devicemapper TCP ReadyTech DeviceMapper Server ReadyTech Corporation -

Registry dates for this port: registered 2013-09-13.

Check what is listening on port 35003

Linux: is anything listening on TCP 35003?
sudo ss -tlnp 'sport = :35003'
Linux / macOS: which process owns the port
sudo lsof -nP -i :35003
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':35003 '
Windows (Command Prompt)
netstat -ano | findstr :35003
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 35003 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 35003
From Windows
Test-NetConnection HOST -Port 35003

Block port 35003 in the firewall

ufw
sudo ufw deny 35003/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 35003 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 35003 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 35003' -Direction Inbound -Protocol TCP -LocalPort 35003 -Action Block

Related ports

35001rt-viewer35002rt-sound35004rt-classmanager35005rt-labtracker

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