2024.12.23 create .ssh directory

$ ssh-keygen
Generating public/private ed25519 key pair.
Enter file in which to save the key (C:\Users\takahiko kondo/.ssh/id_ed25519): id_ed25519
Enter passphrase (empty for no passphrase):恵美あさひ
Enter same passphrase again:恵美あさひ
Your identification has been saved in id_ed25519
Your public key has been saved in id_ed25519.pub
The key fingerprint is:
SHA256:1CnVrWhrs6PiRM3u6U1VtBr2XuXoib63rdKH9heruCM takahiko kondo@LAPTOP-95SFRIEF
The key's randomart image is:
+--[ED25519 256]--+
|          .. ..  |
|         o ..... |
|        o o.o.o .|
|       + .o..= o.|
|      . S. .o o o|
|     . .  +. + + |
|      . ...o..+.o|
|     ... Eooo =oo|
|     ..o=.o+=*+=+|
+----[SHA256]-----+
$ ll
total 6
-rwx---r-x+ 1 takahiko kondo なし 113 Dec 23 13:19 id_ed25519.pub*
-rwx------+ 1 takahiko kondo なし 484 Dec 23 13:19 id_ed25519*
-rw-r--r--  1 takahiko kondo なし 709 Dec 23 13:20 memo.here

but 
A
$ ssh-copy-id -i ~/.ssh/id_ed25519 kondo@atlaspc7.kek.jp
-bash: ssh-copy-id: command not found

Following https://qiita.com/nanbuwks/items/47248b6ed2d37086e40d
B
 email to transfer id_ed25519
B
 then using FM2   login to atlaspc7 and copied
to .ssh/authoriszed_keys
removing ------    --------
-----BEGIN OPENSSH PRIVATE KEY-----
-----ENd OPENSSH PRIVATE KEY-----

OK with
$ ssh -oHostKeyAlgorithms=+ssh-dss kondo@130.87.243.80
(kondo@130.87.243.80) Password:

alias atlaspc7='ssh -Y -oHostKeyAlgorithms=+ssh-dss kondo@atlaspc7.kek.jp'

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For Ubuntu4

ssh-keygen -t dsa
----> .ssh/id_dsa id_dsa.pub
scp id_dsa.pub kondo@lxplus.cern.ch:  ==> cut&paste 
--> atlaspc7/.ssh/authorized_keysに追加 

alias atlaspc7='ssh -Y -oHostKeyAlgorithms=+ssh-dss kondo@atlaspc7.kek.jp'

Ubuntu4からでるとき保存すること。でもそこから再起動するとconnectionが切れる。
電源OFfにするとなぜかssh設定が失われる（Windows11, FM3）
今のところいちいちkeygenするのかなあ。
　
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Virtualboxからの起動
新しいubuntuXは設定で、