[plug] "strobe" the main ports plus specifc ports on all PC's within the network?

[Senectus .]

Back when I was an ignorant Windows user I had a really nice app that
would "strobe" or ports scan a whole subnet on request and dump out a
very nice report on What OS's each host that replied was plus what
ports they had open and other sometimes useful information (services
running etc).

Is there some tool *nix based tool for doing that out there that does
the same thing?

The end result is I want to be able to crank this thing off twice a
day for a few days over the next few weeks to get an idea of what's
out there on the network I'm at for the next few weeks.

Ideally it would work like the other app, via the network only and not
require any agents or clients to be installed other than on my PC.

Thanks
Marcus

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