Mostly, they not really something to worry about. I was going through the logs since my code had bugs and found the authorization attempts by accident.
If you have SELinux, audit.log shows all unauthorized attempts to do anything (log in, access a file, etc.). If not, auth.log is your friend.
@Sp3000 Nobody knows about the new server yet, so it can't be a directed attack. With only 2³² IP addresses, searching for ones that have port 22 open is easy.
I'm surprised so few distros have these security measures activated by default.
It's a big headache to get working, but when it does, it gives you very fine-grained control regarding what action can or cannot be performed in a certain context.
Some other distros have AppArmor which is supposedly easier to use. Haven't tried it though.
Having server-side interpreters is the whole idea of TIO. It can run a great deal of languages, and adding a new language doesn't usually doesn't require anything but cloning a repo and set up two configuration files. Also, in-browser JavaScript is very slow compared to what you can do with a server.
@Sp3000 There's actually a shorter domain already that I'm using with the new server. It's still secret though.
"This is a Ruby program that generates Scala program that generates Scheme program that generates ...(through 100 languages in total)... REXX program that generates the original Ruby code again."
Hm, there's an issue I hadn't considered yet. If somebody can edit all of his permalinks, he can "rage quit" can delete everything he posted. That would make the permalinks a lot less permanent...
I'm probably overthinking this anyway. Additional storage costs $0.10 per GB per month. If TIO becomes popular enough, I'll hopefully be able to cover that with donations.