HTTPfy

Port 3291 (sah-lm)

IANA assigns port 3291 to sah-lm: S A Holditch & Associates - LM.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
sah-lm TCP S A Holditch & Associates - LM Randy Hudgens -
sah-lm UDP S A Holditch & Associates - LM Randy Hudgens -

Check what is listening on port 3291

Linux: is anything listening on TCP 3291?
sudo ss -tlnp 'sport = :3291'
Linux: UDP 3291
sudo ss -ulnp 'sport = :3291'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3291
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3291 '
Windows (Command Prompt)
netstat -ano | findstr :3291
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3291 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3291
From Windows
Test-NetConnection HOST -Port 3291
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3291

Block port 3291 in the firewall

ufw
sudo ufw deny 3291/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3291 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3291 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3291' -Direction Inbound -Protocol TCP -LocalPort 3291 -Action Block
ufw
sudo ufw deny 3291/udp
iptables
sudo iptables -A INPUT -p udp --dport 3291 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3291 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3291' -Direction Inbound -Protocol UDP -LocalPort 3291 -Action Block

Related ports

3289enpc3290caps-lm3292cart-o-rama3293fg-fps

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