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Port 3709 (ca-idms)

IANA assigns port 3709 to ca-idms: CA-IDMS Server.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference
ca-idms TCP CA-IDMS Server Dave Ross -
ca-idms UDP CA-IDMS Server Dave Ross -

Check what is listening on port 3709

Linux: is anything listening on TCP 3709?
sudo ss -tlnp 'sport = :3709'
Linux: UDP 3709
sudo ss -ulnp 'sport = :3709'
Linux / macOS: which process owns the port
sudo lsof -nP -i :3709
Older Linux / BSD (net-tools)
sudo netstat -tlnp | grep ':3709 '
Windows (Command Prompt)
netstat -ano | findstr :3709
Windows (PowerShell)
Get-NetTCPConnection -LocalPort 3709 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine
nc -vz -w 5 HOST 3709
From Windows
Test-NetConnection HOST -Port 3709
UDP probe (no reply does not prove it is closed)
nc -vzu -w 5 HOST 3709

Block port 3709 in the firewall

ufw
sudo ufw deny 3709/tcp
iptables
sudo iptables -A INPUT -p tcp --dport 3709 -j DROP
nftables
sudo nft add rule inet filter input tcp dport 3709 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block TCP 3709' -Direction Inbound -Protocol TCP -LocalPort 3709 -Action Block
ufw
sudo ufw deny 3709/udp
iptables
sudo iptables -A INPUT -p udp --dport 3709 -j DROP
nftables
sudo nft add rule inet filter input udp dport 3709 drop
Windows Firewall
New-NetFirewallRule -DisplayName 'Block UDP 3709' -Direction Inbound -Protocol UDP -LocalPort 3709 -Action Block

Related ports

3707rt-event-s3708sun-as-iiops3710portgate-auth3711edb-server2

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