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SSH_CONFIG(5)		  FreeBSD File Formats Manual		 SSH_CONFIG(5)

NAME
     ssh_config	-- OpenSSH client configuration	file

DESCRIPTION
     ssh(1) obtains configuration data from the	following sources in the fol-
     lowing order:

	   1.	command-line options
	   2.	user's configuration file (~/.ssh/config)
	   3.	system-wide configuration file (/etc/ssh/ssh_config)

     For each parameter, the first obtained value will be used.	 The configu-
     ration files contain sections separated by	Host specifications, and that
     section is	only applied for hosts that match one of the patterns given in
     the specification.	 The matched host name is usually the one given	on the
     command line (see the CanonicalizeHostname	option for exceptions).

     Since the first obtained value for	each parameter is used,	more host-spe-
     cific declarations	should be given	near the beginning of the file,	and
     general defaults at the end.

     The file contains keyword-argument	pairs, one per line.  Lines starting
     with `#' and empty	lines are interpreted as comments.  Arguments may op-
     tionally be enclosed in double quotes (") in order	to represent arguments
     containing	spaces.	 Configuration options may be separated	by whitespace
     or	optional whitespace and	exactly	one `='; the latter format is useful
     to	avoid the need to quote	whitespace when	specifying configuration op-
     tions using the ssh, scp, and sftp	-o option.

     The possible keywords and their meanings are as follows (note that	key-
     words are case-insensitive	and arguments are case-sensitive):

     Host    Restricts the following declarations (up to the next Host or
	     Match keyword) to be only for those hosts that match one of the
	     patterns given after the keyword.	If more	than one pattern is
	     provided, they should be separated	by whitespace.	A single `*'
	     as	a pattern can be used to provide global	defaults for all
	     hosts.  The host is usually the hostname argument given on	the
	     command line (see the CanonicalizeHostname	keyword	for excep-
	     tions).

	     A pattern entry may be negated by prefixing it with an exclama-
	     tion mark (`!').  If a negated entry is matched, then the Host
	     entry is ignored, regardless of whether any other patterns	on the
	     line match.  Negated matches are therefore	useful to provide ex-
	     ceptions for wildcard matches.

	     See PATTERNS for more information on patterns.

     Match   Restricts the following declarations (up to the next Host or
	     Match keyword) to be used only when the conditions	following the
	     Match keyword are satisfied.  Match conditions are	specified us-
	     ing one or	more criteria or the single token all which always
	     matches.  The available criteria keywords are: canonical, final,
	     exec, host, originalhost, user, and localuser.  The all criteria
	     must appear alone or immediately after canonical or final.	 Other
	     criteria may be combined arbitrarily.  All	criteria but all,
	     canonical,	and final require an argument.	Criteria may be
	     negated by	prepending an exclamation mark (`!').

	     The canonical keyword matches only	when the configuration file is
	     being re-parsed after hostname canonicalization (see the
	     CanonicalizeHostname option).  This may be	useful to specify con-
	     ditions that work with canonical host names only.

	     The final keyword requests	that the configuration be re-parsed
	     (regardless of whether CanonicalizeHostname is enabled), and
	     matches only during this final pass.  If CanonicalizeHostname is
	     enabled, then canonical and final match during the	same pass.

	     The exec keyword executes the specified command under the user's
	     shell.  If	the command returns a zero exit	status then the	condi-
	     tion is considered	true.  Commands	containing whitespace charac-
	     ters must be quoted.  Arguments to	exec accept the	tokens de-
	     scribed in	the TOKENS section.

	     The other keywords' criteria must be single entries or comma-sep-
	     arated lists and may use the wildcard and negation	operators de-
	     scribed in	the PATTERNS section.  The criteria for	the host key-
	     word are matched against the target hostname, after any substitu-
	     tion by the Hostname or CanonicalizeHostname options.  The
	     originalhost keyword matches against the hostname as it was spec-
	     ified on the command-line.	 The user keyword matches against the
	     target username on	the remote host.  The localuser	keyword
	     matches against the name of the local user	running	ssh(1) (this
	     keyword may be useful in system-wide ssh_config files).

     AddKeysToAgent
	     Specifies whether keys should be automatically added to a running
	     ssh-agent(1).  If this option is set to yes and a key is loaded
	     from a file, the key and its passphrase are added to the agent
	     with the default lifetime,	as if by ssh-add(1).  If this option
	     is	set to ask, ssh(1) will	require	confirmation using the
	     SSH_ASKPASS program before	adding a key (see ssh-add(1) for de-
	     tails).  If this option is	set to confirm,	each use of the	key
	     must be confirmed,	as if the -c option was	specified to
	     ssh-add(1).  If this option is set	to no, no keys are added to
	     the agent.	 Alternately, this option may be specified as a	time
	     interval using the	format described in the	TIME FORMATS section
	     of	sshd_config(5) to specify the key's lifetime in	ssh-agent(1),
	     after which it will automatically be removed.  The	argument must
	     be	no (the	default), yes, confirm (optionally followed by a time
	     interval),	ask or a time interval.

     AddressFamily
	     Specifies which address family to use when	connecting.  Valid ar-
	     guments are any (the default), inet (use IPv4 only), or inet6
	     (use IPv6 only).

     BatchMode
	     If	set to yes, user interaction such as password prompts and host
	     key confirmation requests will be disabled.  This option is use-
	     ful in scripts and	other batch jobs where no user is present to
	     interact with ssh(1).  The	argument must be yes or	no (the	de-
	     fault).

     BindAddress
	     Use the specified address on the local machine as the source ad-
	     dress of the connection.  Only useful on systems with more	than
	     one address.

     BindInterface
	     Use the address of	the specified interface	on the local machine
	     as	the source address of the connection.

     CanonicalDomains
	     When CanonicalizeHostname is enabled, this	option specifies the
	     list of domain suffixes in	which to search	for the	specified des-
	     tination host.

     CanonicalizeFallbackLocal
	     Specifies whether to fail with an error when hostname canonical-
	     ization fails.  The default, yes, will attempt to look up the un-
	     qualified hostname	using the system resolver's search rules.  A
	     value of no will cause ssh(1) to fail instantly if
	     CanonicalizeHostname is enabled and the target hostname cannot be
	     found in any of the domains specified by CanonicalDomains.

     CanonicalizeHostname
	     Controls whether explicit hostname	canonicalization is performed.
	     The default, no, is not to	perform	any name rewriting and let the
	     system resolver handle all	hostname lookups.  If set to yes then,
	     for connections that do not use a ProxyCommand or ProxyJump,
	     ssh(1) will attempt to canonicalize the hostname specified	on the
	     command line using	the CanonicalDomains suffixes and
	     CanonicalizePermittedCNAMEs rules.	 If CanonicalizeHostname is
	     set to always, then canonicalization is applied to	proxied	con-
	     nections too.

	     If	this option is enabled,	then the configuration files are pro-
	     cessed again using	the new	target name to pick up any new config-
	     uration in	matching Host and Match	stanzas.

     CanonicalizeMaxDots
	     Specifies the maximum number of dot characters in a hostname be-
	     fore canonicalization is disabled.	 The default, 1, allows	a sin-
	     gle dot (i.e. hostname.subdomain).

     CanonicalizePermittedCNAMEs
	     Specifies rules to	determine whether CNAMEs should	be followed
	     when canonicalizing hostnames.  The rules consist of one or more
	     arguments of source_domain_list:target_domain_list, where
	     source_domain_list	is a pattern-list of domains that may follow
	     CNAMEs in canonicalization, and target_domain_list	is a pattern-
	     list of domains that they may resolve to.

	     For example, "*.a.example.com:*.b.example.com,*.c.example.com"
	     will allow	hostnames matching "*.a.example.com" to	be canonical-
	     ized to names in the "*.b.example.com" or "*.c.example.com" do-
	     mains.

     CASignatureAlgorithms
	     Specifies which algorithms	are allowed for	signing	of certifi-
	     cates by certificate authorities (CAs).  The default is:

		   ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,
		   ssh-ed25519,rsa-sha2-512,rsa-sha2-256,ssh-rsa

	     ssh(1) will not accept host certificates signed using algorithms
	     other than	those specified.

     CertificateFile
	     Specifies a file from which the user's certificate	is read.  A
	     corresponding private key must be provided	separately in order to
	     use this certificate either from an IdentityFile directive	or -i
	     flag to ssh(1), via ssh-agent(1), or via a	PKCS11Provider or
	     SecurityKeyProvider.

	     Arguments to CertificateFile may use the tilde syntax to refer to
	     a user's home directory, the tokens described in the TOKENS sec-
	     tion and environment variables as described in the	ENVIRONMENT
	     VARIABLES section.

	     It	is possible to have multiple certificate files specified in
	     configuration files; these	certificates will be tried in se-
	     quence.  Multiple CertificateFile directives will add to the list
	     of	certificates used for authentication.

     ChallengeResponseAuthentication
	     Specifies whether to use challenge-response authentication.  The
	     argument to this keyword must be yes (the default)	or no.

     CheckHostIP
	     If	set to yes (the	default), ssh(1) will additionally check the
	     host IP address in	the known_hosts	file.  This allows it to de-
	     tect if a host key	changed	due to DNS spoofing and	will add ad-
	     dresses of	destination hosts to ~/.ssh/known_hosts	in the
	     process, regardless of the	setting	of StrictHostKeyChecking.  If
	     the option	is set to no, the check	will not be executed.

     Ciphers
	     Specifies the ciphers allowed and their order of preference.
	     Multiple ciphers must be comma-separated.	If the specified list
	     begins with a `+' character, then the specified ciphers will be
	     appended to the default set instead of replacing them.  If	the
	     specified list begins with	a `-' character, then the specified
	     ciphers (including	wildcards) will	be removed from	the default
	     set instead of replacing them.  If	the specified list begins with
	     a `^' character, then the specified ciphers will be placed	at the
	     head of the default set.

	     The supported ciphers are:

		   3des-cbc
		   aes128-cbc
		   aes192-cbc
		   aes256-cbc
		   aes128-ctr
		   aes192-ctr
		   aes256-ctr
		   aes128-gcm@openssh.com
		   aes256-gcm@openssh.com
		   chacha20-poly1305@openssh.com

	     The default is:

		   chacha20-poly1305@openssh.com,
		   aes128-ctr,aes192-ctr,aes256-ctr,
		   aes128-gcm@openssh.com,aes256-gcm@openssh.com

	     The list of available ciphers may also be obtained	using "ssh -Q
	     cipher".

     ClearAllForwardings
	     Specifies that all	local, remote, and dynamic port	forwardings
	     specified in the configuration files or on	the command line be
	     cleared.  This option is primarily	useful when used from the
	     ssh(1) command line to clear port forwardings set in configura-
	     tion files, and is	automatically set by scp(1) and	sftp(1).  The
	     argument must be yes or no	(the default).

     Compression
	     Specifies whether to use compression.  The	argument must be yes
	     or	no (the	default).

     ConnectionAttempts
	     Specifies the number of tries (one	per second) to make before ex-
	     iting.  The argument must be an integer.  This may	be useful in
	     scripts if	the connection sometimes fails.	 The default is	1.

     ConnectTimeout
	     Specifies the timeout (in seconds)	used when connecting to	the
	     SSH server, instead of using the default system TCP timeout.
	     This timeout is applied both to establishing the connection and
	     to	performing the initial SSH protocol handshake and key ex-
	     change.

     ControlMaster
	     Enables the sharing of multiple sessions over a single network
	     connection.  When set to yes, ssh(1) will listen for connections
	     on	a control socket specified using the ControlPath argument.
	     Additional	sessions can connect to	this socket using the same
	     ControlPath with ControlMaster set	to no (the default).  These
	     sessions will try to reuse	the master instance's network connec-
	     tion rather than initiating new ones, but will fall back to con-
	     necting normally if the control socket does not exist, or is not
	     listening.

	     Setting this to ask will cause ssh(1) to listen for control con-
	     nections, but require confirmation	using ssh-askpass(1).  If the
	     ControlPath cannot	be opened, ssh(1) will continue	without	con-
	     necting to	a master instance.

	     X11 and ssh-agent(1) forwarding is	supported over these multi-
	     plexed connections, however the display and agent forwarded will
	     be	the one	belonging to the master	connection i.e.	it is not pos-
	     sible to forward multiple displays	or agents.

	     Two additional options allow for opportunistic multiplexing: try
	     to	use a master connection	but fall back to creating a new	one if
	     one does not already exist.  These	options	are: auto and autoask.
	     The latter	requires confirmation like the ask option.

     ControlPath
	     Specify the path to the control socket used for connection	shar-
	     ing as described in the ControlMaster section above or the	string
	     none to disable connection	sharing.  Arguments to ControlPath may
	     use the tilde syntax to refer to a	user's home directory, the to-
	     kens described in the TOKENS section and environment variables as
	     described in the ENVIRONMENT VARIABLES section.  It is recom-
	     mended that any ControlPath used for opportunistic	connection
	     sharing include at	least %h, %p, and %r (or alternatively %C) and
	     be	placed in a directory that is not writable by other users.
	     This ensures that shared connections are uniquely identified.

     ControlPersist
	     When used in conjunction with ControlMaster, specifies that the
	     master connection should remain open in the background (waiting
	     for future	client connections) after the initial client connec-
	     tion has been closed.  If set to no (the default),	then the mas-
	     ter connection will not be	placed into the	background, and	will
	     close as soon as the initial client connection is closed.	If set
	     to	yes or 0, then the master connection will remain in the	back-
	     ground indefinitely (until	killed or closed via a mechanism such
	     as	the "ssh -O exit").  If	set to a time in seconds, or a time in
	     any of the	formats	documented in sshd_config(5), then the back-
	     grounded master connection	will automatically terminate after it
	     has remained idle (with no	client connections) for	the specified
	     time.

     DynamicForward
	     Specifies that a TCP port on the local machine be forwarded over
	     the secure	channel, and the application protocol is then used to
	     determine where to	connect	to from	the remote machine.

	     The argument must be [bind_address:]port.	IPv6 addresses can be
	     specified by enclosing addresses in square	brackets.  By default,
	     the local port is bound in	accordance with	the GatewayPorts set-
	     ting.  However, an	explicit bind_address may be used to bind the
	     connection	to a specific address.	The bind_address of localhost
	     indicates that the	listening port be bound	for local use only,
	     while an empty address or `*' indicates that the port should be
	     available from all	interfaces.

	     Currently the SOCKS4 and SOCKS5 protocols are supported, and
	     ssh(1) will act as	a SOCKS	server.	 Multiple forwardings may be
	     specified,	and additional forwardings can be given	on the command
	     line.  Only the superuser can forward privileged ports.

     EnableSSHKeysign
	     Setting this option to yes	in the global client configuration
	     file /etc/ssh/ssh_config enables the use of the helper program
	     ssh-keysign(8) during HostbasedAuthentication.  The argument must
	     be	yes or no (the default).  This option should be	placed in the
	     non-hostspecific section.	See ssh-keysign(8) for more informa-
	     tion.

     EscapeChar
	     Sets the escape character (default: `~').	The escape character
	     can also be set on	the command line.  The argument	should be a
	     single character, `^' followed by a letter, or none to disable
	     the escape	character entirely (making the connection transparent
	     for binary	data).

     ExitOnForwardFailure
	     Specifies whether ssh(1) should terminate the connection if it
	     cannot set	up all requested dynamic, tunnel, local, and remote
	     port forwardings, (e.g. if	either end is unable to	bind and lis-
	     ten on a specified	port).	Note that ExitOnForwardFailure does
	     not apply to connections made over	port forwardings and will not,
	     for example, cause	ssh(1) to exit if TCP connections to the ulti-
	     mate forwarding destination fail.	The argument must be yes or no
	     (the default).

     FingerprintHash
	     Specifies the hash	algorithm used when displaying key finger-
	     prints.  Valid options are: md5 and sha256	(the default).

     ForwardAgent
	     Specifies whether the connection to the authentication agent (if
	     any) will be forwarded to the remote machine.  The	argument may
	     be	yes, no	(the default), an explicit path	to an agent socket or
	     the name of an environment	variable (beginning with `$') in which
	     to	find the path.

	     Agent forwarding should be	enabled	with caution.  Users with the
	     ability to	bypass file permissions	on the remote host (for	the
	     agent's Unix-domain socket) can access the	local agent through
	     the forwarded connection.	An attacker cannot obtain key material
	     from the agent, however they can perform operations on the	keys
	     that enable them to authenticate using the	identities loaded into
	     the agent.

     ForwardX11
	     Specifies whether X11 connections will be automatically redi-
	     rected over the secure channel and	DISPLAY	set.  The argument
	     must be yes or no (the default).

	     X11 forwarding should be enabled with caution.  Users with	the
	     ability to	bypass file permissions	on the remote host (for	the
	     user's X11	authorization database)	can access the local X11 dis-
	     play through the forwarded	connection.  An	attacker may then be
	     able to perform activities	such as	keystroke monitoring if	the
	     ForwardX11Trusted option is also enabled.

     ForwardX11Timeout
	     Specify a timeout for untrusted X11 forwarding using the format
	     described in the TIME FORMATS section of sshd_config(5).  X11
	     connections received by ssh(1) after this time will be refused.
	     Setting ForwardX11Timeout to zero will disable the	timeout	and
	     permit X11	forwarding for the life	of the connection.  The	de-
	     fault is to disable untrusted X11 forwarding after	twenty minutes
	     has elapsed.

     ForwardX11Trusted
	     If	this option is set to yes, remote X11 clients will have	full
	     access to the original X11	display.

	     If	this option is set to no (the default),	remote X11 clients
	     will be considered	untrusted and prevented	from stealing or tam-
	     pering with data belonging	to trusted X11 clients.	 Furthermore,
	     the xauth(1) token	used for the session will be set to expire af-
	     ter 20 minutes.  Remote clients will be refused access after this
	     time.

	     See the X11 SECURITY extension specification for full details on
	     the restrictions imposed on untrusted clients.

     GatewayPorts
	     Specifies whether remote hosts are	allowed	to connect to local
	     forwarded ports.  By default, ssh(1) binds	local port forwardings
	     to	the loopback address.  This prevents other remote hosts	from
	     connecting	to forwarded ports.  GatewayPorts can be used to spec-
	     ify that ssh should bind local port forwardings to	the wildcard
	     address, thus allowing remote hosts to connect to forwarded
	     ports.  The argument must be yes or no (the default).

     GlobalKnownHostsFile
	     Specifies one or more files to use	for the	global host key	data-
	     base, separated by	whitespace.  The default is
	     /etc/ssh/ssh_known_hosts, /etc/ssh/ssh_known_hosts2.

     GSSAPIAuthentication
	     Specifies whether user authentication based on GSSAPI is allowed.
	     The default is no.

     GSSAPIDelegateCredentials
	     Forward (delegate)	credentials to the server.  The	default	is no.

     HashKnownHosts
	     Indicates that ssh(1) should hash host names and addresses	when
	     they are added to ~/.ssh/known_hosts.  These hashed names may be
	     used normally by ssh(1) and sshd(8), but they do not visually re-
	     veal identifying information if the file's	contents are dis-
	     closed.  The default is no.  Note that existing names and ad-
	     dresses in	known hosts files will not be converted	automatically,
	     but may be	manually hashed	using ssh-keygen(1).

     HostbasedAuthentication
	     Specifies whether to try rhosts based authentication with public
	     key authentication.  The argument must be yes or no (the de-
	     fault).

     HostbasedKeyTypes
	     Specifies the key types that will be used for hostbased authenti-
	     cation as a comma-separated list of patterns.  Alternately	if the
	     specified list begins with	a `+' character, then the specified
	     key types will be appended	to the default set instead of replac-
	     ing them.	If the specified list begins with a `-'	character,
	     then the specified	key types (including wildcards)	will be	re-
	     moved from	the default set	instead	of replacing them.  If the
	     specified list begins with	a `^' character, then the specified
	     key types will be placed at the head of the default set.  The de-
	     fault for this option is:

		ecdsa-sha2-nistp256-cert-v01@openssh.com,
		ecdsa-sha2-nistp384-cert-v01@openssh.com,
		ecdsa-sha2-nistp521-cert-v01@openssh.com,
		sk-ecdsa-sha2-nistp256-cert-v01@openssh.com,
		ssh-ed25519-cert-v01@openssh.com,
		sk-ssh-ed25519-cert-v01@openssh.com,
		rsa-sha2-512-cert-v01@openssh.com,
		rsa-sha2-256-cert-v01@openssh.com,
		ssh-rsa-cert-v01@openssh.com,
		ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,
		sk-ecdsa-sha2-nistp256@openssh.com,
		ssh-ed25519,sk-ssh-ed25519@openssh.com,
		rsa-sha2-512,rsa-sha2-256,ssh-rsa

	     The -Q option of ssh(1) may be used to list supported key types.

     HostKeyAlgorithms
	     Specifies the host	key algorithms that the	client wants to	use in
	     order of preference.  Alternately if the specified	list begins
	     with a `+'	character, then	the specified key types	will be	ap-
	     pended to the default set instead of replacing them.  If the
	     specified list begins with	a `-' character, then the specified
	     key types (including wildcards) will be removed from the default
	     set instead of replacing them.  If	the specified list begins with
	     a `^' character, then the specified key types will	be placed at
	     the head of the default set.  The default for this	option is:

		ecdsa-sha2-nistp256-cert-v01@openssh.com,
		ecdsa-sha2-nistp384-cert-v01@openssh.com,
		ecdsa-sha2-nistp521-cert-v01@openssh.com,
		sk-ecdsa-sha2-nistp256-cert-v01@openssh.com,
		ssh-ed25519-cert-v01@openssh.com,
		sk-ssh-ed25519-cert-v01@openssh.com,
		rsa-sha2-512-cert-v01@openssh.com,
		rsa-sha2-256-cert-v01@openssh.com,
		ssh-rsa-cert-v01@openssh.com,
		ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,
		sk-ecdsa-sha2-nistp256@openssh.com,
		ssh-ed25519,sk-ssh-ed25519@openssh.com,
		rsa-sha2-512,rsa-sha2-256,ssh-rsa

	     If	hostkeys are known for the destination host then this default
	     is	modified to prefer their algorithms.

	     The list of available key types may also be obtained using	"ssh
	     -Q	HostKeyAlgorithms".

     HostKeyAlias
	     Specifies an alias	that should be used instead of the real	host
	     name when looking up or saving the	host key in the	host key data-
	     base files	and when validating host certificates.	This option is
	     useful for	tunneling SSH connections or for multiple servers run-
	     ning on a single host.

     Hostname
	     Specifies the real	host name to log into.	This can be used to
	     specify nicknames or abbreviations	for hosts.  Arguments to
	     Hostname accept the tokens	described in the TOKENS	section.  Nu-
	     meric IP addresses	are also permitted (both on the	command	line
	     and in Hostname specifications).  The default is the name given
	     on	the command line.

     IdentitiesOnly
	     Specifies that ssh(1) should only use the configured authentica-
	     tion identity and certificate files (either the default files, or
	     those explicitly configured in the	ssh_config files or passed on
	     the ssh(1)	command-line), even if ssh-agent(1) or a
	     PKCS11Provider or SecurityKeyProvider offers more identities.
	     The argument to this keyword must be yes or no (the default).
	     This option is intended for situations where ssh-agent offers
	     many different identities.

     IdentityAgent
	     Specifies the UNIX-domain socket used to communicate with the au-
	     thentication agent.

	     This option overrides the SSH_AUTH_SOCK environment variable and
	     can be used to select a specific agent.  Setting the socket name
	     to	none disables the use of an authentication agent.  If the
	     string "SSH_AUTH_SOCK" is specified, the location of the socket
	     will be read from the SSH_AUTH_SOCK environment variable.	Other-
	     wise if the specified value begins	with a `$' character, then it
	     will be treated as	an environment variable	containing the loca-
	     tion of the socket.

	     Arguments to IdentityAgent	may use	the tilde syntax to refer to a
	     user's home directory, the	tokens described in the	TOKENS section
	     and environment variables as described in the ENVIRONMENT
	     VARIABLES section.

     IdentityFile
	     Specifies a file from which the user's DSA, ECDSA,	authenticator-
	     hosted ECDSA, Ed25519, authenticator-hosted Ed25519 or RSA	au-
	     thentication identity is read.  The default is ~/.ssh/id_dsa,
	     ~/.ssh/id_ecdsa, ~/.ssh/id_ecdsa_sk, ~/.ssh/id_ed25519,
	     ~/.ssh/id_ed25519_sk and ~/.ssh/id_rsa.  Additionally, any	iden-
	     tities represented	by the authentication agent will be used for
	     authentication unless IdentitiesOnly is set.  If no certificates
	     have been explicitly specified by CertificateFile,	ssh(1) will
	     try to load certificate information from the filename obtained by
	     appending -cert.pub to the	path of	a specified IdentityFile.

	     Arguments to IdentityFile may use the tilde syntax	to refer to a
	     user's home directory or the tokens described in the TOKENS sec-
	     tion.

	     It	is possible to have multiple identity files specified in con-
	     figuration	files; all these identities will be tried in sequence.
	     Multiple IdentityFile directives will add to the list of identi-
	     ties tried	(this behaviour	differs	from that of other configura-
	     tion directives).

	     IdentityFile may be used in conjunction with IdentitiesOnly to
	     select which identities in	an agent are offered during authenti-
	     cation.  IdentityFile may also be used in conjunction with
	     CertificateFile in	order to provide any certificate also needed
	     for authentication	with the identity.

     IgnoreUnknown
	     Specifies a pattern-list of unknown options to be ignored if they
	     are encountered in	configuration parsing.	This may be used to
	     suppress errors if	ssh_config contains options that are unrecog-
	     nised by ssh(1).  It is recommended that IgnoreUnknown be listed
	     early in the configuration	file as	it will	not be applied to un-
	     known options that	appear before it.

     Include
	     Include the specified configuration file(s).  Multiple pathnames
	     may be specified and each pathname	may contain glob(7) wildcards
	     and, for user configurations, shell-like `~' references to	user
	     home directories.	Wildcards will be expanded and processed in
	     lexical order.  Files without absolute paths are assumed to be in
	     ~/.ssh if included	in a user configuration	file or	/etc/ssh if
	     included from the system configuration file.  Include directive
	     may appear	inside a Match or Host block to	perform	conditional
	     inclusion.

     IPQoS   Specifies the IPv4	type-of-service	or DSCP	class for connections.
	     Accepted values are af11, af12, af13, af21, af22, af23, af31,
	     af32, af33, af41, af42, af43, cs0,	cs1, cs2, cs3, cs4, cs5, cs6,
	     cs7, ef, le, lowdelay, throughput,	reliability, a numeric value,
	     or	none to	use the	operating system default.  This	option may
	     take one or two arguments,	separated by whitespace.  If one argu-
	     ment is specified,	it is used as the packet class uncondition-
	     ally.  If two values are specified, the first is automatically
	     selected for interactive sessions and the second for non-interac-
	     tive sessions.  The default is af21 (Low-Latency Data) for	inter-
	     active sessions and cs1 (Lower Effort) for	non-interactive	ses-
	     sions.

     KbdInteractiveAuthentication
	     Specifies whether to use keyboard-interactive authentication.
	     The argument to this keyword must be yes (the default) or no.

     KbdInteractiveDevices
	     Specifies the list	of methods to use in keyboard-interactive au-
	     thentication.  Multiple method names must be comma-separated.
	     The default is to use the server specified	list.  The methods
	     available vary depending on what the server supports.  For	an
	     OpenSSH server, it	may be zero or more of:	bsdauth, pam, and
	     skey.

     KexAlgorithms
	     Specifies the available KEX (Key Exchange)	algorithms.  Multiple
	     algorithms	must be	comma-separated.  If the specified list	begins
	     with a `+'	character, then	the specified methods will be appended
	     to	the default set	instead	of replacing them.  If the specified
	     list begins with a	`-' character, then the	specified methods (in-
	     cluding wildcards)	will be	removed	from the default set instead
	     of	replacing them.	 If the	specified list begins with a `^' char-
	     acter, then the specified methods will be placed at the head of
	     the default set.  The default is:

		   curve25519-sha256,curve25519-sha256@libssh.org,
		   ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,
		   diffie-hellman-group-exchange-sha256,
		   diffie-hellman-group16-sha512,
		   diffie-hellman-group18-sha512,
		   diffie-hellman-group14-sha256

	     The list of available key exchange	algorithms may also be ob-
	     tained using "ssh -Q kex".

     LocalCommand
	     Specifies a command to execute on the local machine after suc-
	     cessfully connecting to the server.  The command string extends
	     to	the end	of the line, and is executed with the user's shell.
	     Arguments to LocalCommand accept the tokens described in the
	     TOKENS section.

	     The command is run	synchronously and does not have	access to the
	     session of	the ssh(1) that	spawned	it.  It	should not be used for
	     interactive commands.

	     This directive is ignored unless PermitLocalCommand has been en-
	     abled.

     LocalForward
	     Specifies that a TCP port on the local machine be forwarded over
	     the secure	channel	to the specified host and port from the	remote
	     machine.  The first argument specifies the	listener and may be
	     [bind_address:]port or a Unix domain socket path.	The second ar-
	     gument is the destination and may be host:hostport	or a Unix do-
	     main socket path if the remote host supports it.

	     IPv6 addresses can	be specified by	enclosing addresses in square
	     brackets.	Multiple forwardings may be specified, and additional
	     forwardings can be	given on the command line.  Only the superuser
	     can forward privileged ports.  By default,	the local port is
	     bound in accordance with the GatewayPorts setting.	 However, an
	     explicit bind_address may be used to bind the connection to a
	     specific address.	The bind_address of localhost indicates	that
	     the listening port	be bound for local use only, while an empty
	     address or	`*' indicates that the port should be available	from
	     all interfaces.  Unix domain socket paths may use the tokens de-
	     scribed in	the TOKENS section and environment variables as	de-
	     scribed in	the ENVIRONMENT	VARIABLES section.

     LogLevel
	     Gives the verbosity level that is used when logging messages from
	     ssh(1).  The possible values are: QUIET, FATAL, ERROR, INFO, VER-
	     BOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3.  The default is INFO.
	     DEBUG and DEBUG1 are equivalent.  DEBUG2 and DEBUG3 each specify
	     higher levels of verbose output.

     MACs    Specifies the MAC (message	authentication code) algorithms	in or-
	     der of preference.	 The MAC algorithm is used for data integrity
	     protection.  Multiple algorithms must be comma-separated.	If the
	     specified list begins with	a `+' character, then the specified
	     algorithms	will be	appended to the	default	set instead of replac-
	     ing them.	If the specified list begins with a `-'	character,
	     then the specified	algorithms (including wildcards) will be re-
	     moved from	the default set	instead	of replacing them.  If the
	     specified list begins with	a `^' character, then the specified
	     algorithms	will be	placed at the head of the default set.

	     The algorithms that contain "-etm"	calculate the MAC after	en-
	     cryption (encrypt-then-mac).  These are considered	safer and
	     their use recommended.

	     The default is:

		   umac-64-etm@openssh.com,umac-128-etm@openssh.com,
		   hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,
		   hmac-sha1-etm@openssh.com,
		   umac-64@openssh.com,umac-128@openssh.com,
		   hmac-sha2-256,hmac-sha2-512,hmac-sha1

	     The list of available MAC algorithms may also be obtained using
	     "ssh -Q mac".

     NoHostAuthenticationForLocalhost
	     Disable host authentication for localhost (loopback addresses).
	     The argument to this keyword must be yes or no (the default).

     NumberOfPasswordPrompts
	     Specifies the number of password prompts before giving up.	 The
	     argument to this keyword must be an integer.  The default is 3.

     PasswordAuthentication
	     Specifies whether to use password authentication.	The argument
	     to	this keyword must be yes (the default) or no.

     PermitLocalCommand
	     Allow local command execution via the LocalCommand	option or us-
	     ing the !command escape sequence in ssh(1).  The argument must be
	     yes or no (the default).

     PKCS11Provider
	     Specifies which PKCS#11 provider to use or	none to	indicate that
	     no	provider should	be used	(the default).	The argument to	this
	     keyword is	a path to the PKCS#11 shared library ssh(1) should use
	     to	communicate with a PKCS#11 token providing keys	for user au-
	     thentication.

     Port    Specifies the port	number to connect on the remote	host.  The de-
	     fault is 22.

     PreferredAuthentications
	     Specifies the order in which the client should try	authentication
	     methods.  This allows a client to prefer one method (e.g.
	     keyboard-interactive) over	another	method (e.g. password).	 The
	     default is:

		   gssapi-with-mic,hostbased,publickey,
		   keyboard-interactive,password

     ProxyCommand
	     Specifies the command to use to connect to	the server.  The com-
	     mand string extends to the	end of the line, and is	executed using
	     the user's	shell `exec' directive to avoid	a lingering shell
	     process.

	     Arguments to ProxyCommand accept the tokens described in the
	     TOKENS section.  The command can be basically anything, and
	     should read from its standard input and write to its standard
	     output.  It should	eventually connect an sshd(8) server running
	     on	some machine, or execute sshd -i somewhere.  Host key manage-
	     ment will be done using the Hostname of the host being connected
	     (defaulting to the	name typed by the user).  Setting the command
	     to	none disables this option entirely.  Note that CheckHostIP is
	     not available for connects	with a proxy command.

	     This directive is useful in conjunction with nc(1)	and its	proxy
	     support.  For example, the	following directive would connect via
	     an	HTTP proxy at 192.0.2.0:

		ProxyCommand /usr/bin/nc -X connect -x 192.0.2.0:8080 %h %p

     ProxyJump
	     Specifies one or more jump	proxies	as either [user@]host[:port]
	     or	an ssh URI.  Multiple proxies may be separated by comma	char-
	     acters and	will be	visited	sequentially.  Setting this option
	     will cause	ssh(1) to connect to the target	host by	first making a
	     ssh(1) connection to the specified	ProxyJump host and then	estab-
	     lishing a TCP forwarding to the ultimate target from there.

	     Note that this option will	compete	with the ProxyCommand option -
	     whichever is specified first will prevent later instances of the
	     other from	taking effect.

	     Note also that the	configuration for the destination host (either
	     supplied via the command-line or the configuration	file) is not
	     generally applied to jump hosts.  ~/.ssh/config should be used if
	     specific configuration is required	for jump hosts.

     ProxyUseFdpass
	     Specifies that ProxyCommand will pass a connected file descriptor
	     back to ssh(1) instead of continuing to execute and pass data.
	     The default is no.

     PubkeyAcceptedKeyTypes
	     Specifies the key types that will be used for public key authen-
	     tication as a comma-separated list	of patterns.  If the specified
	     list begins with a	`+' character, then the	key types after	it
	     will be appended to the default instead of	replacing it.  If the
	     specified list begins with	a `-' character, then the specified
	     key types (including wildcards) will be removed from the default
	     set instead of replacing them.  If	the specified list begins with
	     a `^' character, then the specified key types will	be placed at
	     the head of the default set.  The default for this	option is:

		ecdsa-sha2-nistp256-cert-v01@openssh.com,
		ecdsa-sha2-nistp384-cert-v01@openssh.com,
		ecdsa-sha2-nistp521-cert-v01@openssh.com,
		sk-ecdsa-sha2-nistp256-cert-v01@openssh.com,
		ssh-ed25519-cert-v01@openssh.com,
		sk-ssh-ed25519-cert-v01@openssh.com,
		rsa-sha2-512-cert-v01@openssh.com,
		rsa-sha2-256-cert-v01@openssh.com,
		ssh-rsa-cert-v01@openssh.com,
		ecdsa-sha2-nistp256,ecdsa-sha2-nistp384,ecdsa-sha2-nistp521,
		sk-ecdsa-sha2-nistp256@openssh.com,
		ssh-ed25519,sk-ssh-ed25519@openssh.com,
		rsa-sha2-512,rsa-sha2-256,ssh-rsa

	     The list of available key types may also be obtained using	"ssh
	     -Q	PubkeyAcceptedKeyTypes".

     PubkeyAuthentication
	     Specifies whether to try public key authentication.  The argument
	     to	this keyword must be yes (the default) or no.

     RekeyLimit
	     Specifies the maximum amount of data that may be transmitted be-
	     fore the session key is renegotiated, optionally followed a maxi-
	     mum amount	of time	that may pass before the session key is	rene-
	     gotiated.	The first argument is specified	in bytes and may have
	     a suffix of `K', `M', or `G' to indicate Kilobytes, Megabytes, or
	     Gigabytes,	respectively.  The default is between `1G' and `4G',
	     depending on the cipher.  The optional second value is specified
	     in	seconds	and may	use any	of the units documented	in the TIME
	     FORMATS section of	sshd_config(5).	 The default value for
	     RekeyLimit	is default none, which means that rekeying is per-
	     formed after the cipher's default amount of data has been sent or
	     received and no time based	rekeying is done.

     RemoteCommand
	     Specifies a command to execute on the remote machine after	suc-
	     cessfully connecting to the server.  The command string extends
	     to	the end	of the line, and is executed with the user's shell.
	     Arguments to RemoteCommand	accept the tokens described in the
	     TOKENS section.

     RemoteForward
	     Specifies that a TCP port on the remote machine be	forwarded over
	     the secure	channel.  The remote port may either be	forwarded to a
	     specified host and	port from the local machine, or	may act	as a
	     SOCKS 4/5 proxy that allows a remote client to connect to arbi-
	     trary destinations	from the local machine.	 The first argument is
	     the listening specification and may be [bind_address:]port	or, if
	     the remote	host supports it, a Unix domain	socket path.  If for-
	     warding to	a specific destination then the	second argument	must
	     be	host:hostport or a Unix	domain socket path, otherwise if no
	     destination argument is specified then the	remote forwarding will
	     be	established as a SOCKS proxy.

	     IPv6 addresses can	be specified by	enclosing addresses in square
	     brackets.	Multiple forwardings may be specified, and additional
	     forwardings can be	given on the command line.  Privileged ports
	     can be forwarded only when	logging	in as root on the remote ma-
	     chine.  Unix domain socket	paths may use the tokens described in
	     the TOKENS	section	and environment	variables as described in the
	     ENVIRONMENT VARIABLES section.

	     If	the port argument is 0,	the listen port	will be	dynamically
	     allocated on the server and reported to the client	at run time.

	     If	the bind_address is not	specified, the default is to only bind
	     to	loopback addresses.  If	the bind_address is `*'	or an empty
	     string, then the forwarding is requested to listen	on all inter-
	     faces.  Specifying	a remote bind_address will only	succeed	if the
	     server's GatewayPorts option is enabled (see sshd_config(5)).

     RequestTTY
	     Specifies whether to request a pseudo-tty for the session.	 The
	     argument may be one of: no	(never request a TTY), yes (always re-
	     quest a TTY when standard input is	a TTY),	force (always request
	     a TTY) or auto (request a TTY when	opening	a login	session).
	     This option mirrors the -t	and -T flags for ssh(1).

     RevokedHostKeys
	     Specifies revoked host public keys.  Keys listed in this file
	     will be refused for host authentication.  Note that if this file
	     does not exist or is not readable,	then host authentication will
	     be	refused	for all	hosts.	Keys may be specified as a text	file,
	     listing one public	key per	line, or as an OpenSSH Key Revocation
	     List (KRL)	as generated by	ssh-keygen(1).	For more information
	     on	KRLs, see the KEY REVOCATION LISTS section in ssh-keygen(1).

     SecurityKeyProvider
	     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.

	     If	the specified value begins with	a `$' character, then it will
	     be	treated	as an environment variable containing the path to the
	     library.

     SendEnv
	     Specifies what variables from the local environ(7)	should be sent
	     to	the server.  The server	must also support it, and the server
	     must be configured	to accept these	environment variables.	Note
	     that the TERM environment variable	is always sent whenever	a
	     pseudo-terminal is	requested as it	is required by the protocol.
	     Refer to AcceptEnv	in sshd_config(5) for how to configure the
	     server.  Variables	are specified by name, which may contain wild-
	     card characters.  Multiple	environment variables may be separated
	     by	whitespace or spread across multiple SendEnv directives.

	     See PATTERNS for more information on patterns.

	     It	is possible to clear previously	set SendEnv variable names by
	     prefixing patterns	with -.	 The default is	not to send any	envi-
	     ronment variables.

     ServerAliveCountMax
	     Sets the number of	server alive messages (see below) which	may be
	     sent without ssh(1) receiving any messages	back from the server.
	     If	this threshold is reached while	server alive messages are be-
	     ing sent, ssh will	disconnect from	the server, terminating	the
	     session.  It is important to note that the	use of server alive
	     messages is very different	from TCPKeepAlive (below).  The	server
	     alive messages are	sent through the encrypted channel and there-
	     fore will not be spoofable.  The TCP keepalive option enabled by
	     TCPKeepAlive is spoofable.	 The server alive mechanism is valu-
	     able when the client or server depend on knowing when a connec-
	     tion has become unresponsive.

	     The default value is 3.  If, for example, ServerAliveInterval
	     (see below) is set	to 15 and ServerAliveCountMax is left at the
	     default, if the server becomes unresponsive, ssh will disconnect
	     after approximately 45 seconds.

     ServerAliveInterval
	     Sets a timeout interval in	seconds	after which if no data has
	     been received from	the server, ssh(1) will	send a message through
	     the encrypted channel to request a	response from the server.  The
	     default is	0, indicating that these messages will not be sent to
	     the server.

     SetEnv  Directly specify one or more environment variables	and their con-
	     tents to be sent to the server.  Similarly	to SendEnv, the	server
	     must be prepared to accept	the environment	variable.

     StreamLocalBindMask
	     Sets the octal file creation mode mask (umask) used when creating
	     a Unix-domain socket file for local or remote port	forwarding.
	     This option is only used for port forwarding to a Unix-domain
	     socket file.

	     The default value is 0177,	which creates a	Unix-domain socket
	     file that is readable and writable	only by	the owner.  Note that
	     not all operating systems honor the file mode on Unix-domain
	     socket files.

     StreamLocalBindUnlink
	     Specifies whether to remove an existing Unix-domain socket	file
	     for local or remote port forwarding before	creating a new one.
	     If	the socket file	already	exists and StreamLocalBindUnlink is
	     not enabled, ssh will be unable to	forward	the port to the	Unix-
	     domain socket file.  This option is only used for port forwarding
	     to	a Unix-domain socket file.

	     The argument must be yes or no (the default).

     StrictHostKeyChecking
	     If	this flag is set to yes, ssh(1)	will never automatically add
	     host keys to the ~/.ssh/known_hosts file, and refuses to connect
	     to	hosts whose host key has changed.  This	provides maximum pro-
	     tection against man-in-the-middle (MITM) attacks, though it can
	     be	annoying when the /etc/ssh/ssh_known_hosts file	is poorly
	     maintained	or when	connections to new hosts are frequently	made.
	     This option forces	the user to manually add all new hosts.

	     If	this flag is set to "accept-new" then ssh will automatically
	     add new host keys to the user known hosts files, but will not
	     permit connections	to hosts with changed host keys.  If this flag
	     is	set to "no" or "off", ssh will automatically add new host keys
	     to	the user known hosts files and allow connections to hosts with
	     changed hostkeys to proceed, subject to some restrictions.	 If
	     this flag is set to ask (the default), new	host keys will be
	     added to the user known host files	only after the user has	con-
	     firmed that is what they really want to do, and ssh will refuse
	     to	connect	to hosts whose host key	has changed.  The host keys of
	     known hosts will be verified automatically	in all cases.

     SyslogFacility
	     Gives the facility	code that is used when logging messages	from
	     ssh(1).  The possible values are: DAEMON, USER, AUTH, LOCAL0, LO-
	     CAL1, LOCAL2, LOCAL3, LOCAL4, LOCAL5, LOCAL6, LOCAL7.  The	de-
	     fault is USER.

     TCPKeepAlive
	     Specifies whether the system should send TCP keepalive messages
	     to	the other side.	 If they are sent, death of the	connection or
	     crash of one of the machines will be properly noticed.  However,
	     this means	that connections will die if the route is down tempo-
	     rarily, and some people find it annoying.

	     The default is yes	(to send TCP keepalive messages), and the
	     client will notice	if the network goes down or the	remote host
	     dies.  This is important in scripts, and many users want it too.

	     To	disable	TCP keepalive messages,	the value should be set	to no.
	     See also ServerAliveInterval for protocol-level keepalives.

     Tunnel  Request tun(4) device forwarding between the client and the
	     server.  The argument must	be yes,	point-to-point (layer 3),
	     ethernet (layer 2), or no (the default).  Specifying yes requests
	     the default tunnel	mode, which is point-to-point.

     TunnelDevice
	     Specifies the tun(4) devices to open on the client	(local_tun)
	     and the server (remote_tun).

	     The argument must be local_tun[:remote_tun].  The devices may be
	     specified by numerical ID or the keyword any, which uses the next
	     available tunnel device.  If remote_tun is	not specified, it de-
	     faults to any.  The default is any:any.

     UpdateHostKeys
	     Specifies whether ssh(1) should accept notifications of addi-
	     tional hostkeys from the server sent after	authentication has
	     completed and add them to UserKnownHostsFile.  The	argument must
	     be	yes, no	or ask.	 This option allows learning alternate
	     hostkeys for a server and supports	graceful key rotation by al-
	     lowing a server to	send replacement public	keys before old	ones
	     are removed.  Additional hostkeys are only	accepted if the	key
	     used to authenticate the host was already trusted or explicitly
	     accepted by the user.

	     UpdateHostKeys is enabled by default if the user has not overrid-
	     den the default UserKnownHostsFile	setting, otherwise
	     UpdateHostKeys will be set	to ask.

	     If	UpdateHostKeys is set to ask, then the user is asked to	con-
	     firm the modifications to the known_hosts file.  Confirmation is
	     currently incompatible with ControlPersist, and will be disabled
	     if	it is enabled.

	     Presently,	only sshd(8) from OpenSSH 6.8 and greater support the
	     "hostkeys@openssh.com" protocol extension used to inform the
	     client of all the server's	hostkeys.

     User    Specifies the user	to log in as.  This can	be useful when a dif-
	     ferent user name is used on different machines.  This saves the
	     trouble of	having to remember to give the user name on the	com-
	     mand line.

     UserKnownHostsFile
	     Specifies one or more files to use	for the	user host key data-
	     base, separated by	whitespace.  Each filename may use tilde nota-
	     tion to refer to the user's home directory, the tokens described
	     in	the TOKENS section and environment variables as	described in
	     the ENVIRONMENT VARIABLES section.	 The default is
	     ~/.ssh/known_hosts, ~/.ssh/known_hosts2.

     VerifyHostKeyDNS
	     Specifies whether to verify the remote key	using DNS and SSHFP
	     resource records.	If this	option is set to yes, the client will
	     implicitly	trust keys that	match a	secure fingerprint from	DNS.
	     Insecure fingerprints will	be handled as if this option was set
	     to	ask.  If this option is	set to ask, information	on fingerprint
	     match will	be displayed, but the user will	still need to confirm
	     new host keys according to	the StrictHostKeyChecking option.  The
	     default is	no.

	     See also VERIFYING	HOST KEYS in ssh(1).

     VisualHostKey
	     If	this flag is set to yes, an ASCII art representation of	the
	     remote host key fingerprint is printed in addition	to the finger-
	     print string at login and for unknown host	keys.  If this flag is
	     set to no (the default), no fingerprint strings are printed at
	     login and only the	fingerprint string will	be printed for unknown
	     host keys.

     XAuthLocation
	     Specifies the full	pathname of the	xauth(1) program.  The default
	     is	/usr/X11R6/bin/xauth.

PATTERNS
     A pattern consists	of zero	or more	non-whitespace characters, `*' (a
     wildcard that matches zero	or more	characters), or	`?' (a wildcard	that
     matches exactly one character).  For example, to specify a	set of decla-
     rations for any host in the ".co.uk" set of domains, the following	pat-
     tern could	be used:

	   Host	*.co.uk

     The following pattern would match any host	in the 192.168.0.[0-9] network
     range:

	   Host	192.168.0.?

     A pattern-list is a comma-separated list of patterns.  Patterns within
     pattern-lists may be negated by preceding them with an exclamation	mark
     (`!').  For example, to allow a key to be used from anywhere within an
     organization except from the "dialup" pool, the following entry (in au-
     thorized_keys) could be used:

	   from="!*.dialup.example.com,*.example.com"

     Note that a negated match will never produce a positive result by itself.
     For example, attempting to	match "host3" against the following pattern-
     list will fail:

	   from="!host1,!host2"

     The solution here is to include a term that will yield a positive match,
     such as a wildcard:

	   from="!host1,!host2,*"

TOKENS
     Arguments to some keywords	can make use of	tokens,	which are expanded at
     runtime:

	   %%	 A literal `%'.
	   %C	 Hash of %l%h%p%r.
	   %d	 Local user's home directory.
	   %h	 The remote hostname.
	   %i	 The local user	ID.
	   %k	 The host key alias if specified, otherwise the	orignal	remote
		 hostname given	on the command line.
	   %L	 The local hostname.
	   %l	 The local hostname, including the domain name.
	   %n	 The original remote hostname, as given	on the command line.
	   %p	 The remote port.
	   %r	 The remote username.
	   %T	 The local tun(4) or tap(4) network interface assigned if tun-
		 nel forwarding	was requested, or "NONE" otherwise.
	   %u	 The local username.

     CertificateFile, ControlPath, IdentityAgent, IdentityFile,	LocalForward,
     Match exec, RemoteCommand,	RemoteForward, and UserKnownHostsFile accept
     the tokens	%%, %C,	%d, %h,	%i, %L,	%l, %n,	%p, %r,	and %u.

     Hostname accepts the tokens %% and	%h.

     LocalCommand accepts all tokens.

     ProxyCommand accepts the tokens %%, %h, %n, %p, and %r.

ENVIRONMENT VARIABLES
     Arguments to some keywords	can be expanded	at runtime from	environment
     variables on the client by	enclosing them in ${}, for example
     ${HOME}/.ssh would	refer to the user's .ssh directory.  If	a specified
     environment variable does not exist then an error will be returned	and
     the setting for that keyword will be ignored.

     The keywords CertificateFile, ControlPath,	IdentityAgent, IdentityFile
     and UserKnownHostsFile support environment	variables.  The	keywords
     LocalForward and RemoteForward support environment	variables only for
     Unix domain socket	paths.

FILES
     ~/.ssh/config
	     This is the per-user configuration	file.  The format of this file
	     is	described above.  This file is used by the SSH client.	Be-
	     cause of the potential for	abuse, this file must have strict per-
	     missions: read/write for the user,	and not	writable by others.

     /etc/ssh/ssh_config
	     Systemwide	configuration file.  This file provides	defaults for
	     those values that are not specified in the	user's configuration
	     file, and for those users who do not have a configuration file.
	     This file must be world-readable.

SEE ALSO
     ssh(1)

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.

FreeBSD	13.0			August 11, 2020			  FreeBSD 13.0

NAME | DESCRIPTION | PATTERNS | TOKENS | ENVIRONMENT VARIABLES | FILES | SEE ALSO | AUTHORS

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