Port 4569 (iax)

IANA assigns port 4569 to iax: Inter-Asterisk eXchange.

Registered (user) port, 1024-49151 TCPUDP

IANA assignment

Service nameProtoDescriptionAssigneeReference

iax TCP Inter-Asterisk eXchange
Defined TXT keys: auth plaintext | md5 | rsakeys userid alphanumeric, additionally '_', '+', '-' secret any printable ASCII characters domain any DNS domain name or IP address extension alphanumeric, additionally '*', '#', '_', '+', '-' context alphanumeric, additionally '_', '+', '-' trunk yes | no | 0 | 1 welcome alphanumeric, additionally '*', '#', '_', '+', '-' voicemail alphanumeric, additionally '*', '#', '_', '+', '-' reception alphanumeric, additionally '*', '#', '_', '+', '-' echotest alphanumeric, additionally '*', '#', '_', '+', '-' ivrtest alphanumeric, additionally '*', '#', '_', '+', '-' All of these TXT record keys are optional, they may be omitted. Further keys may be added in the future. Benjamin Kowarsch RFC 5456

iax UDP Inter-Asterisk eXchange
Defined TXT keys: auth plaintext | md5 | rsakeys userid alphanumeric, additionally '_', '+', '-' secret any printable ASCII characters domain any DNS domain name or IP address extension alphanumeric, additionally '*', '#', '_', '+', '-' context alphanumeric, additionally '_', '+', '-' trunk yes | no | 0 | 1 welcome alphanumeric, additionally '*', '#', '_', '+', '-' voicemail alphanumeric, additionally '*', '#', '_', '+', '-' reception alphanumeric, additionally '*', '#', '_', '+', '-' echotest alphanumeric, additionally '*', '#', '_', '+', '-' ivrtest alphanumeric, additionally '*', '#', '_', '+', '-' All of these TXT record keys are optional, they may be omitted. Further keys may be added in the future. Benjamin Kowarsch RFC 5456

Check what is listening on port 4569

Linux: is anything listening on TCP 4569?

sudo ss -tlnp 'sport = :4569'

Linux: UDP 4569

sudo ss -ulnp 'sport = :4569'

Linux / macOS: which process owns the port

sudo lsof -nP -i :4569

Older Linux / BSD (net-tools)

sudo netstat -tlnp | grep ':4569 '

Windows (Command Prompt)

netstat -ano | findstr :4569

Windows (PowerShell)

Get-NetTCPConnection -LocalPort 4569 -State Listen | Select LocalAddress,OwningProcess

Test it from outside

From another machine

nc -vz -w 5 HOST 4569

From Windows

Test-NetConnection HOST -Port 4569

UDP probe (no reply does not prove it is closed)

nc -vzu -w 5 HOST 4569

Block port 4569 in the firewall

ufw

sudo ufw deny 4569/tcp

iptables

sudo iptables -A INPUT -p tcp --dport 4569 -j DROP

nftables

sudo nft add rule inet filter input tcp dport 4569 drop

Windows Firewall

New-NetFirewallRule -DisplayName 'Block TCP 4569' -Direction Inbound -Protocol TCP -LocalPort 4569 -Action Block

ufw

sudo ufw deny 4569/udp