ssh-add --- adds private key identities to the authentication agent


     ssh-add [-cDdkLlXx] [-E fingerprint_hash] [-t life] [file ...]
     ssh-add -s pkcs11
     ssh-add -e pkcs11


     ssh-add adds private key identities to the authentication agent,
     ssh-agent(1).  When run without arguments, it adds the files
     ~/.ssh/id_rsa, ~/.ssh/id_dsa, ~/.ssh/id_ecdsa, ~/.ssh/id_ed25519 and
     ~/.ssh/identity.  After loading a private key, ssh-add will try to load
     corresponding certificate information from the filename obtained by
     appending to the name of the private key file.  Alternative
     file names can be given on the command line.

     If any file requires a passphrase, ssh-add asks for the passphrase from
     the user.  The passphrase is read from the user's tty.  ssh-add retries
     the last passphrase if multiple identity files are given.

     The authentication agent must be running and the SSH_AUTH_SOCK
     environment variable must contain the name of its socket for ssh-add to

     The options are as follows:

     -c      Indicates that added identities should be subject to confirmation
         before being used for authentication.  Confirmation is performed
         by ssh-askpass(1).  Successful confirmation is signaled by a zero
         exit status from ssh-askpass(1), rather than text entered into
         the requester.

     -D      Deletes all identities from the agent.

     -d      Instead of adding identities, removes identities from the agent.
         If ssh-add has been run without arguments, the keys for the
         default identities and their corresponding certificates will be
         removed.  Otherwise, the argument list will be interpreted as a
         list of paths to public key files to specify keys and
         certificates to be removed from the agent.  If no public key is
         found at a given path, ssh-add will append .pub and retry.

     -E fingerprint_hash
         Specifies the hash algorithm used when displaying key
         fingerprints.  Valid options are: "md5" and "sha256".  The
         default is "sha256".

     -e pkcs11
         Remove keys provided by the PKCS#11 shared library pkcs11.

     -k      When loading keys into or deleting keys from the agent, process
         plain private keys only and skip certificates.

     -L      Lists public key parameters of all identities currently
         represented by the agent.

     -l      Lists fingerprints of all identities currently represented by the

     -s pkcs11
         Add keys provided by the PKCS#11 shared library pkcs11.

     -t life
         Set a maximum lifetime when adding identities to an agent.  The
         lifetime may be specified in seconds or in a time format
         specified in sshd_config(5).

     -X      Unlock the agent.

     -x      Lock the agent with a password.


         If ssh-add needs a passphrase, it will read the passphrase from
         the current terminal if it was run from a terminal.  If ssh-add
         does not have a terminal associated with it but DISPLAY and
         SSH_ASKPASS are set, it will execute the program specified by
         SSH_ASKPASS (by default "ssh-askpass") and open an X11 window to
         read the passphrase.  This is particularly useful when calling
         ssh-add from a .xsession or related script.  (Note that on some
         machines it may be necessary to redirect the input from /dev/null
         to make this work.)

         Identifies the path of a UNIX-domain socket used to communicate
         with the agent.


         Contains the protocol version 1 RSA authentication identity of
         the user.

         Contains the protocol version 2 DSA authentication identity of
         the user.

         Contains the protocol version 2 ECDSA authentication identity of
         the user.

         Contains the protocol version 2 Ed25519 authentication identity
         of the user.

         Contains the protocol version 2 RSA authentication identity of
         the user.

     Identity files should not be readable by anyone but the user.  Note that
     ssh-add ignores identity files if they are accessible by others.


     Exit status is 0 on success, 1 if the specified command fails, and 2 if
     ssh-add is unable to contact the authentication agent.


     ssh(1), ssh-agent(1), ssh-askpass(1), ssh-keygen(1), sshd(8)


     OpenSSH is a derivative of the original and free ssh 1.2.12 release by
     Tatu Ylonen.  Aaron Campbell, Bob Beck, Markus Friedl, Niels Provos, Theo
     de Raadt and Dug Song removed many bugs, re-added newer features and
     created OpenSSH.  Markus Friedl contributed the support for SSH protocol
     versions 1.5 and 2.0.


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