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NAME | SYNOPSIS | DESCRIPTION | AUTHENTICATION | LOGIN PROCESS | SSHRC | AUTHORIZED_KEYS FILE FORMAT | SSH_KNOWN_HOSTS FILE FORMAT | FILES | SEE ALSO | AUTHORS | COLOPHON |
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SSHD(8) System Manager's Manual SSHD(8)
sshd — OpenSSH daemon
sshd [-46DdeGiqTtV] [-C connection_spec]
[-c host_certificate_file] [-E log_file] [-f config_file]
[-g login_grace_time] [-h host_key_file] [-o option] [-p port]
[-u len]
sshd (OpenSSH Daemon) is the daemon program for ssh(1). It
provides secure encrypted communications between two untrusted
hosts over an insecure network.
sshd listens for connections from clients. It is normally
started at boot from /etc/rc. It forks a new daemon for each
incoming connection. The forked daemons handle key exchange,
encryption, authentication, command execution, and data exchange.
sshd can be configured using command-line options or a
configuration file (by default sshd_config(5)); command-line
options override values specified in the configuration file.
sshd rereads its configuration file when it receives a hangup
signal, SIGHUP, by executing itself with the name and options it
was started with, e.g. /usr/sbin/sshd.
The options are as follows:
-4 Forces sshd to use IPv4 addresses only.
-6 Forces sshd to use IPv6 addresses only.
-C connection_spec
Specify the connection parameters to use for the -T
extended test mode. If provided, any Match directives in
the configuration file that would apply are applied
before the configuration is written to standard output.
The connection parameters are supplied as keyword=value
pairs and may be supplied in any order, either with
multiple -C options or as a comma-separated list. The
keywords are “addr”, “user”, “host”, “laddr”, “lport”,
and “rdomain” and correspond to source address, user,
resolved source host name, local address, local port
number and routing domain respectively.
-c host_certificate_file
Specifies a path to a certificate file to identify sshd
during key exchange. The certificate file must match a
host key file specified using the -h option or the
HostKey configuration directive.
-D When this option is specified, sshd will not detach and
does not become a daemon. This allows easy monitoring of
sshd.
-d Debug mode. The server sends verbose debug output to
standard error, and does not put itself in the
background. The server also will not fork(2) and will
only process one connection. This option is only
intended for debugging for the server. Multiple -d
options increase the debugging level. Maximum is 3.
-E log_file
Append debug logs to log_file instead of the system log.
-e Write debug logs to standard error instead of the system
log.
-f config_file
Specifies the name of the configuration file. The
default is /etc/ssh/sshd_config. sshd refuses to start
if there is no configuration file.
-G Parse and print configuration file. Check the validity
of the configuration file, output the effective
configuration to stdout and then exit. Optionally, Match
rules may be applied by specifying the connection
parameters using one or more -C options.
-g login_grace_time
Gives the grace time for clients to authenticate
themselves (default 120 seconds). If the client fails to
authenticate the user within this many seconds, the
server disconnects and exits. A value of zero indicates
no limit.
-h host_key_file
Specifies a file from which a host key is read. This
option must be given if sshd is not run as root (as the
normal host key files are normally not readable by anyone
but root). The default is /etc/ssh/ssh_host_ecdsa_key,
/etc/ssh/ssh_host_ed25519_key and
/etc/ssh/ssh_host_rsa_key. It is possible to have
multiple host key files for the different host key
algorithms.
-i Specifies that sshd is being run from inetd(8).
-o option
Can be used to give options in the format used in the
configuration file. This is useful for specifying
options for which there is no separate command-line flag.
For full details of the options, and their values, see
sshd_config(5).
-p port
Specifies the port on which the server listens for
connections (default 22). Multiple port options are
permitted. Ports specified in the configuration file
with the Port option are ignored when a command-line port
is specified. Ports specified using the ListenAddress
option override command-line ports.
-q Quiet mode. Nothing is sent to the system log. Normally
the beginning, authentication, and termination of each
connection is logged.
-T Extended test mode. Check the validity of the
configuration file, output the effective configuration to
stdout and then exit. Optionally, Match rules may be
applied by specifying the connection parameters using one
or more -C options. This is similar to the -G flag, but
it includes the additional testing performed by the -t
flag.
-t Test mode. Only check the validity of the configuration
file and sanity of the keys. This is useful for updating
sshd reliably as configuration options may change.
-u len This option is used to specify the size of the field in
the utmp structure that holds the remote host name. If
the resolved host name is longer than len, the dotted
decimal value will be used instead. This allows hosts
with very long host names that overflow this field to
still be uniquely identified. Specifying -u0 indicates
that only dotted decimal addresses should be put into the
utmp file. -u0 may also be used to prevent sshd from
making DNS requests unless the authentication mechanism
or configuration requires it. Authentication mechanisms
that may require DNS include HostbasedAuthentication and
using a from="pattern-list" option in a key file.
Configuration options that require DNS include using a
USER@HOST pattern in AllowUsers or DenyUsers.
-V Display the version number and exit.
The OpenSSH SSH daemon supports SSH protocol 2 only. Each host
has a host-specific key, used to identify the host. Whenever a
client connects, the daemon responds with its public host key.
The client compares the host key against its own database to
verify that it has not changed. Forward secrecy is provided
through a Diffie-Hellman key agreement. This key agreement
results in a shared session key. The rest of the session is
encrypted using a symmetric cipher. The client selects the
encryption algorithm to use from those offered by the server.
Additionally, session integrity is provided through a
cryptographic message authentication code (MAC).
Finally, the server and the client enter an authentication
dialog. The client tries to authenticate itself using host-based
authentication, public key authentication, challenge-response
authentication, or password authentication.
Regardless of the authentication type, the account is checked to
ensure that it is accessible. An account is not accessible if it
is locked, listed in DenyUsers or its group is listed in
DenyGroups . The definition of a locked account is system
dependent. Some platforms have their own account database (eg
AIX) and some modify the passwd field ( ‘*LK*’ on Solaris and
UnixWare, ‘*’ on HP-UX, containing ‘Nologin’ on Tru64, a leading
‘*LOCKED*’ on FreeBSD and a leading ‘!’ on most Linuxes). If
there is a requirement to disable password authentication for the
account while allowing still public-key, then the passwd field
should be set to something other than these values (eg ‘NP’ or
‘*NP*’ ).
If the client successfully authenticates itself, a dialog for
preparing the session is entered. At this time the client may
request things like allocating a pseudo-tty, forwarding X11
connections, forwarding TCP connections, or forwarding the
authentication agent connection over the secure channel.
After this, the client either requests an interactive shell or
execution of a non-interactive command, which sshd will execute
via the user's shell using its -c option. The sides then enter
session mode. In this mode, either side may send data at any
time, and such data is forwarded to/from the shell or command on
the server side, and the user terminal in the client side.
When the user program terminates and all forwarded X11 and other
connections have been closed, the server sends command exit
status to the client, and both sides exit.
When a user successfully logs in, sshd does the following:
1. If the login is on a tty, and no command has been
specified, prints last login time and /etc/motd
(unless prevented in the configuration file or by
~/.hushlogin; see the “FILES” section).
2. If the login is on a tty, records login time.
3. Checks /etc/nologin; if it exists, prints contents and
quits (unless root).
4. Changes to run with normal user privileges.
5. Sets up basic environment.
6. Reads the file ~/.ssh/environment, if it exists, and
users are allowed to change their environment. See
the PermitUserEnvironment option in sshd_config(5).
7. Changes to user's home directory.
8. If ~/.ssh/rc exists and the sshd_config(5)
PermitUserRC option is set, runs it; else if
/etc/ssh/sshrc exists, runs it; otherwise runs
xauth(1). The “rc” files are given the X11
authentication protocol and cookie in standard input.
See “SSHRC”, below.
9. Runs user's shell or command. All commands are run
under the user's login shell as specified in the
system password database.
If the file ~/.ssh/rc exists, sh(1) runs it after reading the
environment files but before starting the user's shell or
command. It must not produce any output on stdout; stderr must
be used instead. If X11 forwarding is in use, it will receive
the "proto cookie" pair in its standard input (and DISPLAY in its
environment). The script must call xauth(1) because sshd will
not run xauth automatically to add X11 cookies.
The primary purpose of this file is to run any initialization
routines which may be needed before the user's home directory
becomes accessible; AFS is a particular example of such an
environment.
This file will probably contain some initialization code followed
by something similar to:
if read proto cookie && [ -n "$DISPLAY" ]; then
if [ `echo $DISPLAY | cut -c1-10` = 'localhost:' ]; then
# X11UseLocalhost=yes
echo add unix:`echo $DISPLAY |
cut -c11-` $proto $cookie
else
# X11UseLocalhost=no
echo add $DISPLAY $proto $cookie
fi | xauth -q -
fi
If this file does not exist, /etc/ssh/sshrc is run, and if that
does not exist either, xauth is used to add the cookie.
AuthorizedKeysFile specifies the files containing public keys for
public key authentication; if this option is not specified, the
default is ~/.ssh/authorized_keys and ~/.ssh/authorized_keys2.
Each line of the file contains one key (empty lines and lines
starting with a ‘#’ are ignored as comments). Public keys
consist of the following space-separated fields: options,
keytype, base64-encoded key, comment. The options field is
optional. The supported key types are:
sk-ecdsa-sha2-nistp256@openssh.com
ecdsa-sha2-nistp256
ecdsa-sha2-nistp384
ecdsa-sha2-nistp521
sk-ssh-ed25519@openssh.com
ssh-ed25519
ssh-dss
ssh-rsa
The comment field is not used for anything (but may be convenient
for the user to identify the key).
Note that lines in this file can be several hundred bytes long
(because of the size of the public key encoding) up to a limit of
8 kilobytes, which permits RSA keys up to 16 kilobits. You don't
want to type them in; instead, copy the id_dsa.pub, id_ecdsa.pub,
id_ecdsa_sk.pub, id_ed25519.pub, id_ed25519_sk.pub, or the
id_rsa.pub file and edit it.
sshd enforces a minimum RSA key modulus size of 1024 bits.
The options (if present) consist of comma-separated option
specifications. No spaces are permitted, except within double
quotes. The following option specifications are supported (note
that option keywords are case-insensitive):
agent-forwarding
Enable authentication agent forwarding previously
disabled by the restrict option.
cert-authority
Specifies that the listed key is a certification
authority (CA) that is trusted to validate signed
certificates for user authentication.
Certificates may encode access restrictions similar to
these key options. If both certificate restrictions and
key options are present, the most restrictive union of
the two is applied.
command="command"
Specifies that the command is executed whenever this key
is used for authentication. The command supplied by the
user (if any) is ignored. The command is run on a pty if
the client requests a pty; otherwise it is run without a
tty. If an 8-bit clean channel is required, one must not
request a pty or should specify no-pty. A quote may be
included in the command by quoting it with a backslash.
This option might be useful to restrict certain public
keys to perform just a specific operation. An example
might be a key that permits remote backups but nothing
else. Note that the client may specify TCP and/or X11
forwarding unless they are explicitly prohibited, e.g.
using the restrict key option.
The command originally supplied by the client is
available in the SSH_ORIGINAL_COMMAND environment
variable. Note that this option applies to shell,
command or subsystem execution. Also note that this
command may be superseded by a sshd_config(5)
ForceCommand directive.
If a command is specified and a forced-command is
embedded in a certificate used for authentication, then
the certificate will be accepted only if the two commands
are identical.
environment="NAME=value"
Specifies that the string is to be added to the
environment when logging in using this key. Environment
variables set this way override other default environment
values. Multiple options of this type are permitted.
Environment processing is disabled by default and is
controlled via the PermitUserEnvironment option.
expiry-time="timespec"
Specifies a time after which the key will not be
accepted. The time may be specified as a YYYYMMDD[Z]
date or a YYYYMMDDHHMM[SS][Z] time. Dates and times will
be interpreted in the system time zone unless suffixed by
a Z character, in which case they will be interpreted in
the UTC time zone.
from="pattern-list"
Specifies that in addition to public key authentication,
either the canonical name of the remote host or its IP
address must be present in the comma-separated list of
patterns. See PATTERNS in ssh_config(5) for more
information on patterns.
In addition to the wildcard matching that may be applied
to hostnames or addresses, a from stanza may match IP
addresses using CIDR address/masklen notation.
The purpose of this option is to optionally increase
security: public key authentication by itself does not
trust the network or name servers or anything (but the
key); however, if somebody somehow steals the key, the
key permits an intruder to log in from anywhere in the
world. This additional option makes using a stolen key
more difficult (name servers and/or routers would have to
be compromised in addition to just the key).
no-agent-forwarding
Forbids authentication agent forwarding when this key is
used for authentication.
no-port-forwarding
Forbids TCP forwarding when this key is used for
authentication. Any port forward requests by the client
will return an error. This might be used, e.g. in
connection with the command option.
no-pty Prevents tty allocation (a request to allocate a pty will
fail).
no-user-rc
Disables execution of ~/.ssh/rc.
no-X11-forwarding
Forbids X11 forwarding when this key is used for
authentication. Any X11 forward requests by the client
will return an error.
permitlisten="[host:]port"
Limit remote port forwarding with the ssh(1) -R option
such that it may only listen on the specified host
(optional) and port. IPv6 addresses can be specified by
enclosing the address in square brackets. Multiple
permitlisten options may be applied separated by commas.
Hostnames may include wildcards as described in the
PATTERNS section in ssh_config(5). A port specification
of * matches any port. Note that the setting of
GatewayPorts may further restrict listen addresses. Note
that ssh(1) will send a hostname of “localhost” if a
listen host was not specified when the forwarding was
requested, and that this name is treated differently to
the explicit localhost addresses “127.0.0.1” and “::1”.
permitopen="host:port"
Limit local port forwarding with the ssh(1) -L option
such that it may only connect to the specified host and
port. IPv6 addresses can be specified by enclosing the
address in square brackets. Multiple permitopen options
may be applied separated by commas. No pattern matching
or name lookup is performed on the specified hostnames,
they must be literal host names and/or addresses. A port
specification of * matches any port.
port-forwarding
Enable port forwarding previously disabled by the
restrict option.
principals="principals"
On a cert-authority line, specifies allowed principals
for certificate authentication as a comma-separated list.
At least one name from the list must appear in the
certificate's list of principals for the certificate to
be accepted. This option is ignored for keys that are
not marked as trusted certificate signers using the
cert-authority option.
pty Permits tty allocation previously disabled by the
restrict option.
no-touch-required
Do not require demonstration of user presence for
signatures made using this key. This option only makes
sense for the FIDO authenticator algorithms ecdsa-sk and
ed25519-sk.
verify-required
Require that signatures made using this key attest that
they verified the user, e.g. via a PIN. This option only
makes sense for the FIDO authenticator algorithms
ecdsa-sk and ed25519-sk.
restrict
Enable all restrictions, i.e. disable port, agent and X11
forwarding, as well as disabling PTY allocation and
execution of ~/.ssh/rc. If any future restriction
capabilities are added to authorized_keys files, they
will be included in this set.
tunnel="n"
Force a tun(4) device on the server. Without this
option, the next available device will be used if the
client requests a tunnel.
user-rc
Enables execution of ~/.ssh/rc previously disabled by the
restrict option.
X11-forwarding
Permits X11 forwarding previously disabled by the
restrict option.
An example authorized_keys file:
# Comments are allowed at start of line. Blank lines are allowed.
# Plain key, no restrictions
ssh-rsa ...
# Forced command, disable PTY and all forwarding
restrict,command="dump /home" ssh-rsa ...
# Restriction of ssh -L forwarding destinations
permitopen="192.0.2.1:80",permitopen="192.0.2.2:25" ssh-rsa ...
# Restriction of ssh -R forwarding listeners
permitlisten="localhost:8080",permitlisten="[::1]:22000" ssh-rsa ...
# Configuration for tunnel forwarding
tunnel="0",command="sh /etc/netstart tun0" ssh-rsa ...
# Override of restriction to allow PTY allocation
restrict,pty,command="nethack" ssh-rsa ...
# Allow FIDO key without requiring touch
no-touch-required sk-ecdsa-sha2-nistp256@openssh.com ...
# Require user-verification (e.g. PIN or biometric) for FIDO key
verify-required sk-ecdsa-sha2-nistp256@openssh.com ...
# Trust CA key, allow touch-less FIDO if requested in certificate
cert-authority,no-touch-required,principals="user_a" ssh-rsa ...
The /etc/ssh/ssh_known_hosts and ~/.ssh/known_hosts files contain
host public keys for all known hosts. The global file should be
prepared by the administrator (optional), and the per-user file
is maintained automatically: whenever the user connects to an
unknown host, its key is added to the per-user file.
Each line in these files contains the following fields: marker
(optional), hostnames, keytype, base64-encoded key, comment. The
fields are separated by spaces.
The marker is optional, but if it is present then it must be one
of “@cert-authority”, to indicate that the line contains a
certification authority (CA) key, or “@revoked”, to indicate that
the key contained on the line is revoked and must not ever be
accepted. Only one marker should be used on a key line.
Hostnames is a comma-separated list of patterns (‘*’ and ‘?’ act
as wildcards); each pattern in turn is matched against the host
name. When sshd is authenticating a client, such as when using
HostbasedAuthentication, this will be the canonical client host
name. When ssh(1) is authenticating a server, this will be the
host name given by the user, the value of the ssh(1) HostkeyAlias
if it was specified, or the canonical server hostname if the
ssh(1) CanonicalizeHostname option was used.
A pattern may also be preceded by ‘!’ to indicate negation: if
the host name matches a negated pattern, it is not accepted (by
that line) even if it matched another pattern on the line. A
hostname or address may optionally be enclosed within ‘[’ and ‘]’
brackets then followed by ‘:’ and a non-standard port number.
Alternately, hostnames may be stored in a hashed form which hides
host names and addresses should the file's contents be disclosed.
Hashed hostnames start with a ‘|’ character. Only one hashed
hostname may appear on a single line and none of the above
negation or wildcard operators may be applied.
The keytype and base64-encoded key are taken directly from the
host key; they can be obtained, for example, from
/etc/ssh/ssh_host_rsa_key.pub. The optional comment field
continues to the end of the line, and is not used.
Lines starting with ‘#’ and empty lines are ignored as comments.
When performing host authentication, authentication is accepted
if any matching line has the proper key; either one that matches
exactly or, if the server has presented a certificate for
authentication, the key of the certification authority that
signed the certificate. For a key to be trusted as a
certification authority, it must use the “@cert-authority” marker
described above.
The known hosts file also provides a facility to mark keys as
revoked, for example when it is known that the associated private
key has been stolen. Revoked keys are specified by including the
“@revoked” marker at the beginning of the key line, and are never
accepted for authentication or as certification authorities, but
instead will produce a warning from ssh(1) when they are
encountered.
It is permissible (but not recommended) to have several lines or
different host keys for the same names. This will inevitably
happen when short forms of host names from different domains are
put in the file. It is possible that the files contain
conflicting information; authentication is accepted if valid
information can be found from either file.
Note that the lines in these files are typically hundreds of
characters long, and you definitely don't want to type in the
host keys by hand. Rather, generate them by a script,
ssh-keyscan(1) or by taking, for example,
/etc/ssh/ssh_host_rsa_key.pub and adding the host names at the
front. ssh-keygen(1) also offers some basic automated editing
for ~/.ssh/known_hosts including removing hosts matching a host
name and converting all host names to their hashed
representations.
An example ssh_known_hosts file:
# Comments allowed at start of line
cvs.example.net,192.0.2.10 ssh-rsa AAAA1234.....=
# A hashed hostname
|1|JfKTdBh7rNbXkVAQCRp4OQoPfmI=|USECr3SWf1JUPsms5AqfD5QfxkM= ssh-rsa
AAAA1234.....=
# A revoked key
@revoked * ssh-rsa AAAAB5W...
# A CA key, accepted for any host in *.mydomain.com or *.mydomain.org
@cert-authority *.mydomain.org,*.mydomain.com ssh-rsa AAAAB5W...
~/.hushlogin
This file is used to suppress printing the last login
time and /etc/motd, if PrintLastLog and PrintMotd,
respectively, are enabled. It does not suppress printing
of the banner specified by Banner.
~/.rhosts
This file is used for host-based authentication (see
ssh(1) for more information). On some machines this file
may need to be world-readable if the user's home
directory is on an NFS partition, because sshd reads it
as root. Additionally, this file must be owned by the
user, and must not have write permissions for anyone
else. The recommended permission for most machines is
read/write for the user, and not accessible by others.
~/.shosts
This file is used in exactly the same way as .rhosts, but
allows host-based authentication without permitting login
with rlogin/rsh.
~/.ssh/
This directory is the default location for all user-
specific configuration and authentication information.
There is no general requirement to keep the entire
contents of this directory secret, but the recommended
permissions are read/write/execute for the user, and not
accessible by others.
~/.ssh/authorized_keys
Lists the public keys (DSA, ECDSA, Ed25519, RSA) that can
be used for logging in as this user. The format of this
file is described above. The content of the file is not
highly sensitive, but the recommended permissions are
read/write for the user, and not accessible by others.
If this file, the ~/.ssh directory, or the user's home
directory are writable by other users, then the file
could be modified or replaced by unauthorized users. In
this case, sshd will not allow it to be used unless the
StrictModes option has been set to “no”.
~/.ssh/environment
This file is read into the environment at login (if it
exists). It can only contain empty lines, comment lines
(that start with ‘#’), and assignment lines of the form
name=value. The file should be writable only by the
user; it need not be readable by anyone else.
Environment processing is disabled by default and is
controlled via the PermitUserEnvironment option.
~/.ssh/known_hosts
Contains a list of host keys for all hosts the user has
logged into that are not already in the systemwide list
of known host keys. The format of this file is described
above. This file should be writable only by root/the
owner and can, but need not be, world-readable.
~/.ssh/rc
Contains initialization routines to be run before the
user's home directory becomes accessible. This file
should be writable only by the user, and need not be
readable by anyone else.
/etc/hosts.equiv
This file is for host-based authentication (see ssh(1)).
It should only be writable by root.
/etc/moduli
Contains Diffie-Hellman groups used for the "Diffie-
Hellman Group Exchange" key exchange method. The file
format is described in moduli(5). If no usable groups
are found in this file then fixed internal groups will be
used.
/etc/motd
See motd(5).
/etc/nologin
If this file exists, sshd refuses to let anyone except
root log in. The contents of the file are displayed to
anyone trying to log in, and non-root connections are
refused. The file should be world-readable.
/etc/shosts.equiv
This file is used in exactly the same way as hosts.equiv,
but allows host-based authentication without permitting
login with rlogin/rsh.
/etc/ssh/ssh_host_ecdsa_key
/etc/ssh/ssh_host_ed25519_key
/etc/ssh/ssh_host_rsa_key
These files contain the private parts of the host keys.
These files should only be owned by root, readable only
by root, and not accessible to others. Note that sshd
does not start if these files are group/world-accessible.
/etc/ssh/ssh_host_ecdsa_key.pub
/etc/ssh/ssh_host_ed25519_key.pub
/etc/ssh/ssh_host_rsa_key.pub
These files contain the public parts of the host keys.
These files should be world-readable but writable only by
root. Their contents should match the respective private
parts. These files are not really used for anything;
they are provided for the convenience of the user so
their contents can be copied to known hosts files. These
files are created using ssh-keygen(1).
/etc/ssh/ssh_known_hosts
Systemwide list of known host keys. This file should be
prepared by the system administrator to contain the
public host keys of all machines in the organization.
The format of this file is described above. This file
should be writable only by root/the owner and should be
world-readable.
/etc/ssh/sshd_config
Contains configuration data for sshd. The file format
and configuration options are described in
sshd_config(5).
/etc/ssh/sshrc
Similar to ~/.ssh/rc, it can be used to specify machine-
specific login-time initializations globally. This file
should be writable only by root, and should be world-
readable.
/var/empty
chroot(2) directory used by sshd during privilege
separation in the pre-authentication phase. The
directory should not contain any files and must be owned
by root and not group or world-writable.
/var/run/sshd.pid
Contains the process ID of the sshd listening for
connections (if there are several daemons running
concurrently for different ports, this contains the
process ID of the one started last). The content of this
file is not sensitive; it can be world-readable.
scp(1), sftp(1), ssh(1), ssh-add(1), ssh-agent(1), ssh-keygen(1),
ssh-keyscan(1), chroot(2), login.conf(5), moduli(5),
sshd_config(5), inetd(8), sftp-server(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.
Niels Provos and Markus Friedl contributed support for privilege
separation.
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-9.7p1.tar.gz
fetched from
⟨http://ftp.eu.openbsd.org/pub/OpenBSD/OpenSSH/portable/⟩ on
2024-06-14. If you discover any rendering problems in this HTML
version of the page, or you believe there is a better or more up-
to-date source for the page, or you have corrections or
improvements to the information in this COLOPHON (which is not
part of the original manual page), send a mail to
man-pages@man7.org
GNU September 19, 2023 SSHD(8)
Pages that refer to this page: systemd-ssh-proxy(1), pts(4), environment.d(5), user@.service(5), systemd-ssh-generator(8)
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