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ssh-add(1)

NAME

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

SYNOPSIS

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

DESCRIPTION

     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 -cert.pub 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
     work.

     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
         agent.

     -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.

ENVIRONMENT

     DISPLAY and SSH_ASKPASS
         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.)

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

FILES

     ~/.ssh/identity
         Contains the protocol version 1 RSA authentication identity of
         the user.

     ~/.ssh/id_dsa
         Contains the protocol version 2 DSA authentication identity of
         the user.

     ~/.ssh/id_ecdsa
         Contains the protocol version 2 ECDSA authentication identity of
         the user.

     ~/.ssh/id_ed25519
         Contains the protocol version 2 Ed25519 authentication identity
         of the user.

     ~/.ssh/id_rsa
         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

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

SEE ALSO

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

AUTHORS

     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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