[colug-432] nc replacement in RHEL7?

[Jeff Frontz]

traceroute -T uses TCP to send a SYN.  It doesn't exit with a non-zero, but
the output indicates success/failure -- I get a "!X" in the output.  Hmm,
that may only come out if the far end has a firewall that silently drops
packets destined for inaccessible ports-- according to the man page,
receiving a "reset" is considered a success (I guess since you were able to
reach the target host).



On Thu, May 28, 2015 at 5:03 PM, Rick Hornsby <richardjhornsby at gmail.com>
wrote:

> but is "traceroute -T -p 80 some host" roughly equivalent?
>
>
> Good thought but it does not appear so.  That command is successful
> regardless of which port I try, including ones known not to be listening.
> It should fail with connection refused or at least exit non-zero. I'm not
> really sure what the port flag is doing - sending some kind of an ICMP echo
> message to that port?
>
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