Hello,
Sorry for the English, I use GoogleTranslate to read the forum
It's not a problem. You could put your public key in "/root/.ssh". I 've done it like this :
my-login@computer:~/$ ssh-copy-id -i ~/.ssh/id_rsa.pub root@mld
/usr/bin/ssh-copy-id: INFO: Source of key(s) to be installed: "/home/my-login/.ssh/id_rsa.pub"
/usr/bin/ssh-copy-id: INFO: attempting to log in with the new key(s), to filter out any that are already installed
/usr/bin/ssh-copy-id: INFO: 1 key(s) remain to be installed -- if you are prompted now it is to install the new keys
root@mld's password:
Permission denied, please try again.
root@mld's password:
Number of key(s) added: 1
Now try logging into the machine, with: "ssh 'root@mld'"
and check to make sure that only the key(s) you wanted were added.
my-login@computer:~$ ssh root@mld
BusyBox v1.25.1 (2018-08-27 03:43:10 CEST) built-in shell (ash)
Enter 'help' for a list of built-in commands.
MLD>
I hope that this could help you.
For the usual "/etc/ssh" directory, it is necessary to manage the SSH access by user, group or other things ... And I don't know how to do that.