The UDP port scan is part of the IP Tools range of network testing tools. The test uses the excellent Nmap Port Scanner to scan 5 of the most common UDP ports. Ports tested in the quick UDP scan are DNS 53 , TFTP 69 , NTP 123 , SNMP 161 , mDNS 5353 , UPNP 1900 and Memcached 11211 .
UDP Scan (-sU) | Nmap Network Scanning record, 53 is the only open UDP port on Scanme. While this version detection technique is the only way for Nmap to automatically disambiguate open|filteredports, there are a couple tricks that can be tried manually. Sometimes a DNS constraints and behaviors - Amazon Route 53 If the resolver supports EDNS0 (as defined in RFC 2671), and advertises the EDNS0 option to Amazon Route 53, Route 53 permits responses up to 4096 bytes over UDP, without truncation.
windows - Port 53 (UDP and TCP) gets blocked when OpenVPN
If the resolver supports EDNS0 (as defined in RFC 2671), and advertises the EDNS0 option to Amazon Route 53, Route 53 permits responses up to 4096 bytes over UDP, without truncation. VPN Ports & Port Forwarding: TCP/UDP 443, 80, 53, 25, 22 Apr 12, 2018 DNS issue open port 53 udp - Cisco Community
You can open (forward) some TCP or UDP ports for troubleshooting. Ports are endpoints between two connections. A port number is assigned to each end, like an address, to direct the flow of internet traffic.
[Question] OpenVPN over port 53 UDP : PFSENSE Fwiw DNS on udp 53 is occasionally being blocked to force you to use the local DNS for caching or security reasons, so using that for openvpn might get caught in same trap. Also DDOS and other anti abuse systems might flag that kind of heavy traffic on udp 53 anyway since DNS runs on it and otherwise considered 'sensitive' Why DNS Works On Both TCP and UDP - TechGenix Oct 31, 2009 Opening ports for connection issues - Electronic Arts Ports are endpoints between two connections. A port number is assigned to each end, like an address, to direct the flow of internet traffic. If you’re having trouble connecting to any of our online games — and you have tried basic connection troubleshooting — you may need to open some ports on your network connection.. Consoles