SSH(Secure Shell)の基礎知識

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% ssh hogehoge@123.456.78.9
The authenticity of host '123.456.78.9 (123.456.78.9)' can not be established.
ECDSA key fingerprint is SHA256:ghzvH/1TBjI0wvlYiRNDJvUsiYAX/R9eip5bw6+Rv10.
Are you sure you want to continue connecting (yes/no/[fingerprint])?
$ yes
Warning: Permanently added '123.456.78.9' (ECDSA) to the list of known hosts.
Password:
Last login: Thu Apr 11 04:16:45 2021

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% ssh ubuntu@12.3.4.56
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@    WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED!     @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@


@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!
It is also possible that a host key has just been changed.
The fingerprint for the ECDSA key sent by the remote host is
SHA256:tfZBzQ16o7O7SH6u4ixBmL061Sxz8DOo1cFZ9oMuGjE.
Please contact your system administrator.
Add correct host key in /home/hogehoge/.ssh/known_hosts to get rid of this message.
Offending ECDSA key in /home/hogehoge/.ssh/known_hosts:4
  remove with:
  ssh-keygen -f "/home/hogehoge/.ssh/known_hosts" -R "12.3.4.56"
ECDSA host key for 12.3.4.56 has changed and you have requested strict checking.
Host key verification failed.

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% ssh [option] <username>@<hostname>

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% ssh-keygen [option]

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% ssh-keygen -t ed25519                                           
Generating public/private ed25519 key pair.
Enter file in which to save the key (/home/hogehoge/.ssh/id_ed25519): hogehoge_ed25519
Enter passphrase (empty for no passphrase): 
Enter same passphrase again: 
Your identification has been saved in hogehoge_ed25519
Your public key has been saved in hogehoge_ed25519.pub
The key fingerprint is:
SHA256:MnM1r0IqwugnLCTEnSHjuPoTk7mdmSMExw+r5cOkrwQ hoge@foofoo
The key's randomart image is:
+--[ED25519 256]--+
|@+%.  o  o       |
|.o.Eo *  + S     |
|. o..oo +        |
|@+%.  o  o       |
| .oo=.= S =      |
|   ..B o + +     |
|    = * . o .    |
| o++o            |
|+B==.. ....      |
+----[SHA256]-----+

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% sudo chmod 400 id_ed25519

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% ssh DEDEDE
% ssh kirby_MBP@100.21.209.82 -p 1000 -i ~/.ssh/my_id_rsa -L 9999:localhost:9999

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% sudo apt install sshpass ## Ubuntu

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% wget http://sourceforge.net/projects/sshpass/files/latest/download -O sshpass.tar.gz
% tar -xvf sshpass.tar.gz
% cd sshpass-1.08
% ./configure
% sudo make install 
% which sshpass ##pathが通っているか確認

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% sshpass -h
Usage: sshpass [-f|-d|-p|-e] [-hV] command parameters
   -f filename   Take password to use from file
   -d number     Use number as file descriptor for getting password
   -p password   Provide password as argument (security unwise)
   -e            Password is passed as env-var "SSHPASS"
   With no parameters - password will be taken from stdin

   -P prompt     Which string should sshpass search for to detect a password prompt
   -v            Be verbose about what you're doing
   -h            Show help (this screen)
   -V            Print version information
At most one of -f, -d, -p or -e should be used

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% sshpass -p '<passphrase>' ssh username@host 

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% sshpass -f <configfilepath> ssh username@host

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% export SSHPASS='my_pass_here'
% echo $SSHPASS
% sshpass -e ssh username@host 

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## ファイルのコピー
% scp ~/tmp/file1 user@192.168.10.1:/home/user/tmp/ 

## ディレクトリのコピー
% scp -r ~/tmp user1@192.168.10.1:/home/user/tmp

## sshpassとの組合せ
% sshpass -f passwordFile scp ~/tmp/file1 user@192.168.10.1:/home/user/tmp/ 

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## ファイルのコピー
% scp user@192.168.10.1:/home/user/file1 ~/tmp
 
## ディレクトリのコピー
% scp -r user@192.168.10.1:/home/user/tmp ~/tmp
 
## 複数のファイルを、{}で囲んで「,」で区切り指定しコピーする例
% scp user@192.168.10.1:/home/user/{file1,file2,file3} ~/tmp

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% scp user1@192.168.10.1:/home/user/tmp/file1 user2@192.168.10.2:/home/user/tmp/