how nginx works i think, by holly:
so you have programs on your server that think they're talking to the internet. like my mastodon tihnks it's talking to the internet directly. but it's not because that would be bad. instead you have nginx sitting between them. the internet talks to nginx and then nginx tells mastodon what it said, and then whatever mastodon says back nginxs says to the internet
@monorail oh so it's kind of like using an rs232 to rs485 conversion thingy
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@Felthry yeah
only one thing can actually talk to the internet at a time, so you have to have nginx in the middle telling everything "oh yeah don't worry, i'm the internet, you're the only one talking to me"
but it says that to both my mastodon instance and to my phpbb board
also nginx knows how to serve files, too, so it itself is one of the things that the internet might be talking to
@monorail addressable buses are very handy when you need to have more than one thing in existence
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@Felthry i find that, quite often, you need more than one thing to exist
@monorail it tends to help yeah
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@monorail @Felthry also most of the first few hundred ports are reserved for services/programs or have been used by services/programs enough that everyone else just acknowledges that
port 666 is Doom's port, for example, they never formally requested that port but even Windows just labels it doom
there's a benefit to not running stuff on the default port, moving ssh to a different port than 22 means that your login service won't get attacked with dictionaries all the time
explainy
@Felthry @monorail one common reason is because nginx can run as root so your actual server that might have holes in it doesn't need to
root is the highest permission level on linux, and you typically need to use them to have a server that listens on ports browsers actually try to connect to
basically, nginx is heavily battle tested, so there's a smaller chance that someone can exploit it and gain root privileges than whatever random and less-tested thing you put behind it
@Felthry in general? ¯\_(ツ)_/¯
in my case, in addition to whatever other benefits it has: mastodon wants to be the only thing talking to the internet, but nginx knows how to talk to more than one thing, and it knows how to tell which thing any given request is for