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_ecdsa_sk,
~/.ssh/id_ed25519, and ~/.ssh/id_ed25519_sk. 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
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
-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. If the argument list consists
of “-” then ssh-add will read public keys to be removed
from standard input.
Specifies the hash algorithm used when displaying key
fingerprints. Valid options are: “md5” and “sha256”. The
default is “sha256”.
Remove keys provided by the PKCS#11 shared library pkcs11.
-K Load resident keys from a FIDO authenticator.
-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.
-q Be quiet after a successful operation.
Specifies a path to a library that will be used when adding
FIDO authenticator-hosted keys, overriding the default of
using the internal USB HID support.
Add keys provided by the PKCS#11 shared library pkcs11.
-T pubkey ...
Tests whether the private keys that correspond to the
specified pubkey files are usable by performing sign and
verify operations on each.
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).
-v Verbose mode. Causes ssh-add to print debugging messages
about its progress. This is helpful in debugging problems.
Multiple -v options increase the verbosity. The maximum is
-X Unlock the agent.
-x Lock the agent with a password.
DISPLAY, SSH_ASKPASS and SSH_ASKPASS_REQUIRE
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.
SSH_ASKPASS_REQUIRE allows further control over the use of
an askpass program. If this variable is set to “never”
then ssh-add will never attempt to use one. If it is set
to “prefer”, then ssh-add will prefer to use the askpass
program instead of the TTY when requesting passwords.
Finally, if the variable is set to “force”, then the
askpass program will be used for all passphrase input
regardless of whether DISPLAY is set.
Identifies the path of a UNIX-domain socket used to
communicate with the agent.
Specifies a path to a library that will be used when
loading any FIDO authenticator-hosted keys, overriding the
default of using the built-in USB HID support.
Contains the DSA, ECDSA, authenticator-hosted ECDSA,
Ed25519, authenticator-hosted Ed25519 or 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
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.
This page is part of the openssh (Portable OpenSSH) project.
Information about the project can be found at
http://www.openssh.com/portable.html. If you have a bug report for
this manual page, see ⟨http://www.openssh.com/report.html⟩. This
page was obtained from the tarball openssh-8.7p1.tar.gz fetched
from ⟨http://ftp.eu.openbsd.org/pub/OpenBSD/OpenSSH/portable/⟩ on
2021-08-27. If you discover any rendering problems in this HTML
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BSD July 14, 2020 BSD