It seems to me someone is trying his luck by bruteforcing for
Yes, that's the likely cause. Any machine connected to the Internet and listening to SSH will be hammered with login attempts, especially for root.
AFAIK there's no recent SSH vulnerability in public knowledge.
Correct. They're just hoping you have a weak, guessable password.
It uses ephemeral (single use) Curve25519 points in X25519 (Curve25519 ECDH) for key agreement and static long term Ed25519 keys for authentication. Like basically every other protocol from around the same era.
If you want to know how some cipher suites for SSH work, you should read the RFCs or openssh documentation (for their extensions). For example:
They wouldn't (and shouldn't) share their private key. But, you can send them your public key, and they can add your public key to their authorized_keys file. This will allow you to authenticate (provided that you have the private key that corresponds to the public key that you gave them).
GPG and SSH are actually designed for different scenarios. GPG is typically used to identify the user so it would make sense for each user to only have one GPG keypair. However, SSH is typically designed to identify the client device - in other words you want each computer to have its its own SSH keypair.
Personally I use Lastpass to manage my GPG key, but ...
You can avoid setting the username there, moving it to the sh config.
On your .ssh/config file place:
And use just example.com above.
Moreover, you can even use a different name as an alias, such as blogmachine:
and it would actually connect to example.com
I really love the power and convenience of running SOCKS5 via ssh to my own server out in the data center (as the posted pointed out). TAhough I think I use the syntax "ssh -f -Nn -D $LOCAL:$LPORT -p $RPORT $USER@$HOST".
Not only does this securely tunnel my DNS requests and on line banking and DNS requests securely past my ISPs prying eyes (once you ...