title: using the same public ssh key on two different accounts
body: <p>here is the situation: i have one machine which lives at my house (lets call it house_machine) and i have another machine at my office (call this one office_machine). im using ssh with dsa key authentication and without password authentication to access home_machine from office_machine. i have set up an ssh server on home_machine and added the public key generated on office_machine to the authorized_keys file on home_machine. this works fine - i can ssh in to home_machine from office_machine just using the key and no password.</p>
  
  <p>now the question: i would like to be able to access home_machine when i visit other offices simply by using the public key belonging to office_machine. ie i would like to put the public key (id_dsa.pub) on a usb drive and just copy it to the .ssh directory at another office. from what i have read on this site, others seem to have been able to do this type of thing, however it isnt working. when i try simply placing id_dsa.pub on a new machine and doing <code>ssh -v user@home_machine</code> the debug message ends with:</p>
  
  <pre>debug1: Offering public key: .ssh/id_dsa
  debug1: Server accepts key: pkalg ssh-dss blen 433
  debug1: read PEM private key done: type DSA
  debug1: Authentications that can continue: publickey
  debug1: No more authentication methods to try.
  Permission denied (publickey).</pre>
  
  <p>my temporary solution has been to set "PasswordAuthentication yes" in sshd_config on home_machine, and just use a password to get to home_machine. however this voids the point of using key-authorisation.</p>
  
  <p>thanks in advance!</p>