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Port 2091 (prp)

IANA assigns port 2091 to prp: PRP.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
prp TCP PRP Amir Peless -
prp UDP PRP Amir Peless -

Check what is listening on port 2091

Linux: is anything listening on TCP 2091?
sudo ss -tlnp 'sport = :2091'
Linux: UDP 2091
sudo ss -ulnp 'sport = :2091'
Linux / macOS: which process owns the port
sudo lsof -nP -i :2091
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':2091 '
Windows (Command Prompt)
netstat -ano | findstr :2091
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 2091 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 2091
From Windows
Test-NetConnection HOST -Port 2091
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 2091

Block port 2091 in the firewall

ufw
sudo ufw deny 2091/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 2091 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 2091 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 2091' -Direction Inbound -Protocol TCP -LocalPort 2091 -Action Block
ufw
sudo ufw deny 2091/udp
iptables
sudo iptables -A INPUT -p udp --dport 2091 -j DROP
nftables
sudo nft add rule inet filter input udp dport 2091 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 2091' -Direction Inbound -Protocol UDP -LocalPort 2091 -Action Block

Related ports

2089sep2090lrp2092descent32093nbx-cc

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