====== SSH - Remote Logon with Public Key ======

<fc #008000>There a two different methods in order to configure a passwordless SSH logon on a remote HOME:</fc>

===== Passwordless SSH key =====

  - Create ssh key pair (private and public key) without password: e.g. ''ssh-keygen -b 4096 -t rsa -f [keyfile_name]'', type ''ENTER'' (empty passphrase) 
  - Configure logon to your remote HOME: Login to remote account and add content of ''[public_keyfile].pub'' (**be careful to choose the file ending in .pub and not the private keyfile!!!**) to the content of ''~/.ssh/authorized_keys''
  - **Please ensure that the folder ~./ssh and the file ~/.ssh/authorized_keys only have access rights for the owner (group and others should have no rwx)**
  - Then you are ready to do remote ssh logon without password :-)
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===== Using the SSH agent =====

  - Test if environment variables ''SSH_AGENT'' and ''SSH_AUTH_SOCK'' are defined; **if not** invoke a new ssh agent via ''eval $(ssh-agent)''
  - Create ssh key pair (private and public key) with password: e.g. ''ssh-keygen -b 4096 -t rsa -f [private_keyfile]'', type a passphrase and hit ''ENTER'' 
  - Add you private key to the ''ssh-agent'': ''ssh-add [private_keyfile]''
  - Configure logon to your remote HOME: Login to remote account and add content of ''[public_keyfile].pub'' (**be careful to choose the file ending in .pub and not the private keyfile!!!**) to the content of ''~/.ssh/authorized_keys''
  - **Please ensure that the folder ~./ssh and the file ~/.ssh/authorized_keys only have access rights for the owner (group and others should have no rwx)**
  - Then you are ready to do remote ssh logon without password :-)
  - BTW: The ssh-agent can be locked by password (''ssh-agent -x''; then type your password) and unlocked (''ssh-agent -X''; then type your password)
  - **''Attention:''** **The ssh-agent is not a permanent keystore! You have to add the private key manually for every new user session to the agent (e.g. on behalf of a script).**


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date of revision: 03-07-2019 © kraus
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