Day1

· toad's blog


How to print hello world using ruby lang.

ruby -e puts 'hello world'

```sh
[todd@nixos:~/git/ruby_koans/koans]$ ruby -e "puts 'hello, world.'"
hello, world.
```

how to list ssh keys in home dir

[todd@nixos:~]$ find ~/.ssh/id_*.pub -exec ssh-keygen -l -f {} ; 256 SHA256:x8u6W/iO4JjXDzyPml6LD2UTWmYLPdPGrngCGbM0wT4 prose@var.lol (ED25519) 3072 SHA256:QP4JSqJU3FmO1Q/Smfgt7ywz+UICMTyGctrgi3ukqM0 todd@butters.io (RSA)

https://pico.sh/faq#permission-denied-when-using-ssh

Can I use pico.sh dev tunnels to grant colleagues access to my local database without opening ports a la wireguard?

What should I do about this fingerprint change warning?

 1[todd@nixos:~]$ ssh toad@pico.sh
 2@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
 3@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
 4@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
 5IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
 6Someone could be eavesdropping on you right now (man-in-the-middle attack)!
 7It is also possible that a host key has just been changed.
 8The fingerprint for the ED25519 key sent by the remote host is
 9SHA256:jEf+VmhneNREXK3vXKDY65CsUjQoUU1iz4fjZgv71/o.
10Please contact your system administrator.
11Add correct host key in /home/todd/.ssh/known_hosts to get rid of this message.
12Offending ED25519 key in /home/todd/.ssh/known_hosts:28
13Host key for pico.sh has changed and you have requested strict checking.
14Host key verification failed.
15
16[todd@nixos:~]$ ssh sillybit@pico.sh -i .ssh/id_ed25519
17@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
18@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
19@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
20IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
21Someone could be eavesdropping on you right now (man-in-the-middle attack)!
22It is also possible that a host key has just been changed.
23The fingerprint for the ED25519 key sent by the remote host is
24SHA256:jEf+VmhneNREXK3vXKDY65CsUjQoUU1iz4fjZgv71/o.
25Please contact your system administrator.
26Add correct host key in /home/todd/.ssh/known_hosts to get rid of this message.
27Offending ED25519 key in /home/todd/.ssh/known_hosts:28
28Host key for pico.sh has changed and you have requested strict checking.
29Host key verification failed.