Multi account with ssh keys on a device
https://www.techaddressed.com/tutorials/add-verify-ssh-keys-gitea/

- Linux
  The permissions have to be set like this
  This means that the permissions on that file are also set incorrectly, and can be adjusted with this:

	`sudo chmod 644 ~/.ssh/known_hosts` : it means read and write for user and read for group and others

	Finally, you may need to adjust the directory permissions as well:

	`sudo chmod 755 ~/.ssh` : it means read,write,execute for user, read,execute for group and others

	This should get you back up and running.
	 
	

	The keys need to be read-writable only by you:

	`chmod 600 ~/.ssh/id_rsa`

	Alternatively, the keys can be only readable by you (this also blocks your write access):

	`chmod 400 ~/.ssh/id_rsa`

	600 appears to be better in most cases, because you don't need to change file permissions later to edit it. (See the comments for more nuances)