Most network protocols are TCP based, so be aware ping uses ICMP and traceroute UDP
Posted by jpluimers on 2021/09/08
Interesting thread: [WayBack] SwiftOnSecurity sur Twitter : “I had this issue in my prev company network. QoS will drop ICMP and you’ll chase your tail. If you want to find out if a network service works, test the service. If you want to know if TCP works, use TCP.… “
So:
tcppingandtcptraceroutefor the win!- remember that some protocols, rely on ICMP or UDP, so ensure these work on your network tool (do not QoC them away!)
[WayBack] Zimmie on Twitter: “It is perhaps worth noting: traceroute does not generally use ICMP. Instead, it uses this horrific UDP port range with a different port for every probe at every hop. 30 hops? That’s 90 different UDP ports you just tried. Makes its value questionable at the best of times.…”
Related:
- [WayBack] tcptraceroute(1) – Linux man page
- [WayBack] traceroute(8) – Linux man page
- [WayBack] ping(8) – Linux man page
- [WayBack] tcpping/tcpping at master · deajan/tcpping · GitHub
–jeroen
The Wiert Corner - irregular stream of stuff 
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