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SSH-ADD(1)		  BSD General Commands Manual		    SSH-ADD(1)

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

SYNOPSIS
     ssh-add [-cDdkLlXx] [-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 environ-
     ment 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 the SSH_ASKPASS program mentioned below.  Successful confirma-
	     tion is signaled by a zero exit status from the SSH_ASKPASS pro-
	     gram, 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 certifi-
	     cates to be removed from the agent.  If no public key is found at
	     a given path, ssh-add will append .pub and retry.

     -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 repre-
	     sented 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 speci-
	     fied 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 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.

     SSH_USE_STRONG_RNG
	     The reseeding of the OpenSSL random generator is usually done
	     from /dev/urandom.	 If the SSH_USE_STRONG_RNG environment vari-
	     able is set to value other than 0 the OpenSSL random generator is
	     reseeded from /dev/random.	 The number of bytes read is defined
	     by the SSH_USE_STRONG_RNG value.  Minimum is 14 bytes.  This set-
	     ting is not recommended on the computers without the hardware
	     random generator because insufficient entropy causes the connec-
	     tion to be blocked until enough entropy is available.

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-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 cre-
     ated OpenSSH.  Markus Friedl contributed the support for SSH protocol
     versions 1.5 and 2.0.

BSD				 July 1, 2016				   BSD