Why nmap skips ports?

All Hello again.
Lock the extra ports, proquanil with Nmap all ports are filtered. Run the web server 300'om port scanning using nmap and it says nothing at all about this port.
Why he "forgets"? So I began to doubt that he Prosonic all ports and I block superfluous.
July 8th 19 at 16:20
2 answers
July 8th 19 at 16:22
By the way the port udp or tcp ? - what settings for scanning in nmap ?
nmap-p 300 hostname - scan port 300
nmap-sT hostname - scan all tcp targeted Magin
and by the way what fairvilla ?
and very stupid question - but exactly the server on the external interface hanging and not on
of course on the outside. scan TCP and UDP? - Tony_Bergstrom18 commented on July 8th 19 at 16:25
July 8th 19 at 16:24
settings tinkering

by default only checks the standards, up to 1024

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