2 ms·
Perhaps a port knock. I don't know the mechanics, but a port knock is hitting pre-defined ports in a pre-defined order. When you "shave and a haircut" the port
by whartung 5y ago
Perhaps a port knock.
I don't know the mechanics, but a port knock is hitting pre-defined ports in a pre-defined order. When you "shave and a haircut" the ports properly, the server opens something up. In this case white listing (gray listing?) the IP that the knock came from.
You could add a layers to it to make it more complicated.
- tptacek 5y agoPlease don't use silly stuff like port knocking. Your SSH server already does a cryptographically sound authentication step. "Port knocking" is even more performative than fail2ban.