path: root/sshd_config.0

SSHD_CONFIG(5)              BSD File Formats Manual             SSHD_CONFIG(5)

^[[1mNAME^[[0m
     ^[[1msshd_config ^[[22mM-bMM-^R OpenSSH SSH daemon configuration file

^[[1mSYNOPSIS^[[0m
     ^[[4m/etc/ssh/sshd_config^[[0m

^[[1mDESCRIPTION^[[0m
     ^[[1msshd ^[[22mreads configuration data from ^[[4m/etc/ssh/sshd_config^[[24m (or the file
     specified with ^[[1mM-bMM-^Rf ^[[22mon the command line).  The file contains keywordM-bM-^@M-^ParguM-bM-^@M-^P
     ment pairs, one per line.  Lines starting with M-bM-^@M-^X#M-bM-^@M-^Y and empty lines are
     interpreted as comments.

     The possible keywords and their meanings are as follows (note that keyM-bM-^@M-^P
     words are caseM-bM-^@M-^Pinsensitive and arguments are caseM-bM-^@M-^Psensitive):

     ^[[1mAFSTokenPassing^[[0m
             Specifies whether an AFS token may be forwarded to the server.
             Default is M-bM-^@M-^\noM-bM-^@M-^].

     ^[[1mAllowGroups^[[0m
             This keyword can be followed by a list of group name patterns,
             separated by spaces.  If specified, login is allowed only for
             users whose primary group or supplementary group list matches one
             of the patterns.  M-bM-^@M-^X*M-bM-^@M-^Y and M-bM-^@M-^XM-bM-^@M-^Y?  can be used as wildcards in the
             patterns.  Only group names are valid; a numerical group ID is
             not recognized.  By default, login is allowed for all groups.

     ^[[1mAllowTcpForwarding^[[0m
             Specifies whether TCP forwarding is permitted.  The default is
             M-bM-^@M-^\yesM-bM-^@M-^].  Note that disabling TCP forwarding does not improve secuM-bM-^@M-^P
             rity unless users are also denied shell access, as they can
             always install their own forwarders.

     ^[[1mAllowUsers^[[0m
             This keyword can be followed by a list of user name patterns,
             separated by spaces.  If specified, login is allowed only for
             user names that match one of the patterns.  M-bM-^@M-^X*M-bM-^@M-^Y and M-bM-^@M-^XM-bM-^@M-^Y?  can be
             used as wildcards in the patterns.  Only user names are valid; a
             numerical user ID is not recognized.  By default, login is
             allowed for all users.  If the pattern takes the form USER@HOST
             then USER and HOST are separately checked, restricting logins to
             particular users from particular hosts.

     ^[[1mAuthorizedKeysFile^[[0m
             Specifies the file that contains the public keys that can be used
             for user authentication.  ^[[1mAuthorizedKeysFile ^[[22mmay contain tokens
             of the form %T which are substituted during connection setM-bM-^@M-^Pup.
             The following tokens are defined: %% is replaced by a literal
             M-bM-^@M-^Y%M-bM-^@M-^Y, %h is replaced by the home directory of the user being
             authenticated and %u is replaced by the username of that user.
             After expansion, ^[[1mAuthorizedKeysFile ^[[22mis taken to be an absolute
             path or one relative to the userM-bM-^@M-^Ys home directory.  The default
             is M-bM-^@M-^\.ssh/authorized_keysM-bM-^@M-^].

     ^[[1mBanner  ^[[22mIn some jurisdictions, sending a warning message before authentiM-bM-^@M-^P
             cation may be relevant for getting legal protection.  The conM-bM-^@M-^P
             tents of the specified file are sent to the remote user before
             authentication is allowed.  This option is only available for
             protocol version 2.  By default, no banner is displayed.

     ^[[1mChallengeResponseAuthentication^[[0m
             Specifies whether challenge response authentication is allowed.
             All authentication styles from login.conf(5) are supported.  The
             default is M-bM-^@M-^\yesM-bM-^@M-^].

     ^[[1mCiphers^[[0m
             Specifies the ciphers allowed for protocol version 2.  Multiple
             ciphers must be commaM-bM-^@M-^Pseparated.  The default is

               M-bM-^@M-^XM-bM-^@M-^Xaes128M-bM-^@M-^Pcbc,3desM-bM-^@M-^Pcbc,blowfishM-bM-^@M-^Pcbc,cast128M-bM-^@M-^Pcbc,arcfour,
                 aes192M-bM-^@M-^Pcbc,aes256M-bM-^@M-^PcbcM-bM-^@M-^YM-bM-^@M-^Y

     ^[[1mClientAliveInterval^[[0m
             Sets a timeout interval in seconds after which if no data has
             been received from the client, ^[[1msshd ^[[22mwill send a message through
             the encrypted channel to request a response from the client.  The
             default is 0, indicating that these messages will not be sent to
             the client.  This option applies to protocol version 2 only.

     ^[[1mClientAliveCountMax^[[0m
             Sets the number of client alive messages (see above) which may be
             sent without ^[[1msshd ^[[22mreceiving any messages back from the client. If
             this threshold is reached while client alive messages are being
             sent, ^[[1msshd ^[[22mwill disconnect the client, terminating the session.
             It is important to note that the use of client alive messages is
             very different from ^[[1mKeepAlive ^[[22m(below). The client alive messages
             are sent through the encrypted channel and therefore will not be
             spoofable. The TCP keepalive option enabled by ^[[1mKeepAlive ^[[22mis
             spoofable. The client alive mechanism is valuable when the client
             or server depend on knowing when a connection has become inacM-bM-^@M-^P
             tive.

             The default value is 3. If ^[[1mClientAliveInterval ^[[22m(above) is set to
             15, and ^[[1mClientAliveCountMax ^[[22mis left at the default, unresponsive
             ssh clients will be disconnected after approximately 45 seconds.

     ^[[1mCompression^[[0m
             Specifies whether compression is allowed.  The argument must be
             M-bM-^@M-^\yesM-bM-^@M-^] or M-bM-^@M-^\noM-bM-^@M-^].  The default is M-bM-^@M-^\yesM-bM-^@M-^].

     ^[[1mDenyGroups^[[0m
             This keyword can be followed by a list of group name patterns,
             separated by spaces.  Login is disallowed for users whose primary
             group or supplementary group list matches one of the patterns.
             M-bM-^@M-^X*M-bM-^@M-^Y and M-bM-^@M-^XM-bM-^@M-^Y?  can be used as wildcards in the patterns.  Only
             group names are valid; a numerical group ID is not recognized.
             By default, login is allowed for all groups.

     ^[[1mDenyUsers^[[0m
             This keyword can be followed by a list of user name patterns,
             separated by spaces.  Login is disallowed for user names that
             match one of the patterns.  M-bM-^@M-^X*M-bM-^@M-^Y and M-bM-^@M-^XM-bM-^@M-^Y?  can be used as wildcards
             in the patterns.  Only user names are valid; a numerical user ID
             is not recognized.  By default, login is allowed for all users.
             If the pattern takes the form USER@HOST then USER and HOST are
             separately checked, restricting logins to particular users from
             particular hosts.

     ^[[1mGatewayPorts^[[0m
             Specifies whether remote hosts are allowed to connect to ports
             forwarded for the client.  By default, ^[[1msshd ^[[22mbinds remote port
             forwardings to the loopback address.  This prevents other remote
             hosts from connecting to forwarded ports.  ^[[1mGatewayPorts ^[[22mcan be
             used to specify that ^[[1msshd ^[[22mshould bind remote port forwardings to
             the wildcard address, thus allowing remote hosts to connect to
             forwarded ports.  The argument must be M-bM-^@M-^\yesM-bM-^@M-^] or M-bM-^@M-^\noM-bM-^@M-^].  The
             default is M-bM-^@M-^\noM-bM-^@M-^].

     ^[[1mHostbasedAuthentication^[[0m
             Specifies whether rhosts or /etc/hosts.equiv authentication
             together with successful public key client host authentication is
             allowed (hostbased authentication).  This option is similar to
             ^[[1mRhostsRSAAuthentication ^[[22mand applies to protocol version 2 only.
             The default is M-bM-^@M-^\noM-bM-^@M-^].

     ^[[1mHostKey^[[0m
             Specifies a file containing a private host key used by SSH.  The
             default is ^[[4m/etc/ssh/ssh_host_key^[[24m for protocol version 1, and
             ^[[4m/etc/ssh/ssh_host_rsa_key^[[24m and ^[[4m/etc/ssh/ssh_host_dsa_key^[[24m for proM-bM-^@M-^P
             tocol version 2.  Note that ^[[1msshd ^[[22mwill refuse to use a file if it
             is group/worldM-bM-^@M-^Paccessible.  It is possible to have multiple host
             key files.  M-bM-^@M-^\rsa1M-bM-^@M-^] keys are used for version 1 and M-bM-^@M-^\dsaM-bM-^@M-^] or M-bM-^@M-^\rsaM-bM-^@M-^]
             are used for version 2 of the SSH protocol.

     ^[[1mIgnoreRhosts^[[0m
             Specifies that ^[[4m.rhosts^[[24m and ^[[4m.shosts^[[24m files will not be used in
             ^[[1mRhostsAuthentication^[[22m, ^[[1mRhostsRSAAuthentication ^[[22mor
             ^[[1mHostbasedAuthentication^[[22m.

             ^[[4m/etc/hosts.equiv^[[24m and ^[[4m/etc/shosts.equiv^[[24m are still used.  The
             default is M-bM-^@M-^\yesM-bM-^@M-^].

     ^[[1mIgnoreUserKnownHosts^[[0m
             Specifies whether ^[[1msshd ^[[22mshould ignore the userM-bM-^@M-^Ys
             ^[[4m$HOME/.ssh/known_hosts^[[24m during ^[[1mRhostsRSAAuthentication ^[[22mor
             ^[[1mHostbasedAuthentication^[[22m.  The default is M-bM-^@M-^\noM-bM-^@M-^].

     ^[[1mKeepAlive^[[0m
             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 temM-bM-^@M-^P
             porarily, and some people find it annoying.  On the other hand,
             if keepalives are not sent, sessions may hang indefinitely on the
             server, leaving M-bM-^@M-^\ghostM-bM-^@M-^] users and consuming server resources.

             The default is M-bM-^@M-^\yesM-bM-^@M-^] (to send keepalives), and the server will
             notice if the network goes down or the client host crashes.  This
             avoids infinitely hanging sessions.

             To disable keepalives, the value should be set to M-bM-^@M-^\noM-bM-^@M-^].

     ^[[1mKerberosAuthentication^[[0m
             Specifies whether Kerberos authentication is allowed.  This can
             be in the form of a Kerberos ticket, or if ^[[1mPasswordAuthentication^[[0m
             is yes, the password provided by the user will be validated
             through the Kerberos KDC.  To use this option, the server needs a
             Kerberos servtab which allows the verification of the KDCM-bM-^@M-^Ys idenM-bM-^@M-^P
             tity.  Default is M-bM-^@M-^\noM-bM-^@M-^].

     ^[[1mKerberosOrLocalPasswd^[[0m
             If set then if password authentication through Kerberos fails
             then the password will be validated via any additional local
             mechanism such as ^[[4m/etc/passwd^[[24m.  Default is M-bM-^@M-^\yesM-bM-^@M-^].

     ^[[1mKerberosTgtPassing^[[0m
             Specifies whether a Kerberos TGT may be forwarded to the server.
             Default is M-bM-^@M-^\noM-bM-^@M-^], as this only works when the Kerberos KDC is
             actually an AFS kaserver.

     ^[[1mKerberosTicketCleanup^[[0m
             Specifies whether to automatically destroy the userM-bM-^@M-^Ys ticket
             cache file on logout.  Default is M-bM-^@M-^\yesM-bM-^@M-^].

     ^[[1mKeyRegenerationInterval^[[0m
             In protocol version 1, the ephemeral server key is automatically
             regenerated after this many seconds (if it has been used).  The
             purpose of regeneration is to prevent decrypting captured sesM-bM-^@M-^P
             sions by later breaking into the machine and stealing the keys.
             The key is never stored anywhere.  If the value is 0, the key is
             never regenerated.  The default is 3600 (seconds).

     ^[[1mListenAddress^[[0m
             Specifies the local addresses ^[[1msshd ^[[22mshould listen on.  The followM-bM-^@M-^P
             ing forms may be used:

                   ^[[1mListenAddress ^[[4m^[[22mhost^[[24m|^[[4mIPv4_addr^[[24m|^[[4mIPv6_addr^[[0m
                   ^[[1mListenAddress ^[[4m^[[22mhost^[[24m|^[[4mIPv4_addr^[[24m:^[[4mport^[[0m
                   ^[[1mListenAddress ^[[22m[^[[4mhost^[[24m|^[[4mIPv6_addr^[[24m]:^[[4mport^[[0m

             If ^[[4mport^[[24m is not specified, ^[[1msshd ^[[22mwill listen on the address and all
             prior ^[[1mPort ^[[22moptions specified. The default is to listen on all
             local addresses.  Multiple ^[[1mListenAddress ^[[22moptions are permitted.
             Additionally, any ^[[1mPort ^[[22moptions must precede this option for non
             port qualified addresses.

     ^[[1mLoginGraceTime^[[0m
             The server disconnects after this time if the user has not sucM-bM-^@M-^P
             cessfully logged in.  If the value is 0, there is no time limit.
             The default is 120 seconds.

     ^[[1mLogLevel^[[0m
             Gives the verbosity level that is used when logging messages from
             ^[[1msshd^[[22m.  The possible values are: QUIET, FATAL, ERROR, INFO, VERM-bM-^@M-^P
             BOSE, DEBUG, DEBUG1, DEBUG2 and DEBUG3.  The default is INFO.
             DEBUG and DEBUG1 are equivalent.  DEBUG2 and DEBUG3 each specify
             higher levels of debugging output.  Logging with a DEBUG level
             violates the privacy of users and is not recommended.

     ^[[1mMACs    ^[[22mSpecifies the available MAC (message authentication code) algoM-bM-^@M-^P
             rithms.  The MAC algorithm is used in protocol version 2 for data
             integrity protection.  Multiple algorithms must be commaM-bM-^@M-^PsepaM-bM-^@M-^P
             rated.  The default is
             M-bM-^@M-^\hmacM-bM-^@M-^Pmd5,hmacM-bM-^@M-^Psha1,hmacM-bM-^@M-^Pripemd160,hmacM-bM-^@M-^Psha1M-bM-^@M-^P96,hmacM-bM-^@M-^Pmd5M-bM-^@M-^P96M-bM-^@M-^].

     ^[[1mMaxStartups^[[0m
             Specifies the maximum number of concurrent unauthenticated conM-bM-^@M-^P
             nections to the ^[[1msshd ^[[22mdaemon.  Additional connections will be
             dropped until authentication succeeds or the ^[[1mLoginGraceTime^[[0m
             expires for a connection.  The default is 10.

             Alternatively, random early drop can be enabled by specifying the
             three colon separated values M-bM-^@M-^\start:rate:fullM-bM-^@M-^] (e.g.,
             "10:30:60").  ^[[1msshd ^[[22mwill refuse connection attempts with a probaM-bM-^@M-^P
             bility of M-bM-^@M-^\rate/100M-bM-^@M-^] (30%) if there are currently M-bM-^@M-^\startM-bM-^@M-^] (10)
             unauthenticated connections.  The probability increases linearly
             and all connection attempts are refused if the number of unauM-bM-^@M-^P
             thenticated connections reaches M-bM-^@M-^\fullM-bM-^@M-^] (60).

     ^[[1mPAMAuthenticationViaKbdInt^[[0m
             Specifies whether PAM challenge response authentication is
             allowed. This allows the use of most PAM challenge response
             authentication modules, but it will allow password authentication
             regardless of whether ^[[1mPasswordAuthentication ^[[22mis enabled.

     ^[[1mPasswordAuthentication^[[0m
             Specifies whether password authentication is allowed.  The
             default is M-bM-^@M-^\yesM-bM-^@M-^].

     ^[[1mPermitEmptyPasswords^[[0m
             When password authentication is allowed, it specifies whether the
             server allows login to accounts with empty password strings.  The
             default is M-bM-^@M-^\noM-bM-^@M-^].

     ^[[1mPermitRootLogin^[[0m
             Specifies whether root can login using ssh(1).  The argument must
             be M-bM-^@M-^\yesM-bM-^@M-^], M-bM-^@M-^\withoutM-bM-^@M-^PpasswordM-bM-^@M-^], M-bM-^@M-^\forcedM-bM-^@M-^PcommandsM-bM-^@M-^PonlyM-bM-^@M-^] or M-bM-^@M-^\noM-bM-^@M-^].
             The default is M-bM-^@M-^\yesM-bM-^@M-^].

             If this option is set to M-bM-^@M-^\withoutM-bM-^@M-^PpasswordM-bM-^@M-^] password authenticaM-bM-^@M-^P
             tion is disabled for root.

             If this option is set to M-bM-^@M-^\forcedM-bM-^@M-^PcommandsM-bM-^@M-^PonlyM-bM-^@M-^] root login with
             public key authentication will be allowed, but only if the
             ^[[4mcommand^[[24m option has been specified (which may be useful for taking
             remote backups even if root login is normally not allowed). All
             other authentication methods are disabled for root.

             If this option is set to M-bM-^@M-^\noM-bM-^@M-^] root is not allowed to login.

     ^[[1mPermitUserEnvironment^[[0m
             Specifies whether ^[[4m~/.ssh/environment^[[24m and ^[[1menvironment= ^[[22moptions in
             ^[[4m~/.ssh/authorized_keys^[[24m are processed by ^[[1msshd^[[22m.  The default is
             M-bM-^@M-^\noM-bM-^@M-^].  Enabling environment processing may enable users to bypass
             access restrictions in some configurations using mechanisms such
             as LD_PRELOAD.

     ^[[1mPidFile^[[0m
             Specifies the file that contains the process ID of the ^[[1msshd ^[[22mdaeM-bM-^@M-^P
             mon.  The default is ^[[4m/var/run/sshd.pid^[[24m.

     ^[[1mPort    ^[[22mSpecifies the port number that ^[[1msshd ^[[22mlistens on.  The default is
             22.  Multiple options of this type are permitted.  See also
             ^[[1mListenAddress^[[22m.

     ^[[1mPrintLastLog^[[0m
             Specifies whether ^[[1msshd ^[[22mshould print the date and time when the
             user last logged in.  The default is M-bM-^@M-^\yesM-bM-^@M-^].

     ^[[1mPrintMotd^[[0m
             Specifies whether ^[[1msshd ^[[22mshould print ^[[4m/etc/motd^[[24m when a user logs in
             interactively.  (On some systems it is also printed by the shell,
             ^[[4m/etc/profile^[[24m, or equivalent.)  The default is M-bM-^@M-^\yesM-bM-^@M-^].

     ^[[1mProtocol^[[0m
             Specifies the protocol versions ^[[1msshd ^[[22msupports.  The possible valM-bM-^@M-^P
             ues are M-bM-^@M-^\1M-bM-^@M-^] and M-bM-^@M-^\2M-bM-^@M-^].  Multiple versions must be commaM-bM-^@M-^Pseparated.
             The default is M-bM-^@M-^\2,1M-bM-^@M-^].  Note that the order of the protocol list
             does not indicate preference, because the client selects among
             multiple protocol versions offered by the server.  Specifying
             M-bM-^@M-^\2,1M-bM-^@M-^] is identical to M-bM-^@M-^\1,2M-bM-^@M-^].

     ^[[1mPubkeyAuthentication^[[0m
             Specifies whether public key authentication is allowed.  The
             default is M-bM-^@M-^\yesM-bM-^@M-^].  Note that this option applies to protocol verM-bM-^@M-^P
             sion 2 only.

     ^[[1mRhostsAuthentication^[[0m
             Specifies whether authentication using rhosts or /etc/hosts.equiv
             files is sufficient.  Normally, this method should not be permitM-bM-^@M-^P
             ted because it is insecure.  ^[[1mRhostsRSAAuthentication ^[[22mshould be
             used instead, because it performs RSAM-bM-^@M-^Pbased host authentication
             in addition to normal rhosts or /etc/hosts.equiv authentication.
             The default is M-bM-^@M-^\noM-bM-^@M-^].  This option applies to protocol version 1
             only.

     ^[[1mRhostsRSAAuthentication^[[0m
             Specifies whether rhosts or /etc/hosts.equiv authentication
             together with successful RSA host authentication is allowed.  The
             default is M-bM-^@M-^\noM-bM-^@M-^].  This option applies to protocol version 1 only.

     ^[[1mRSAAuthentication^[[0m
             Specifies whether pure RSA authentication is allowed.  The
             default is M-bM-^@M-^\yesM-bM-^@M-^].  This option applies to protocol version 1
             only.

     ^[[1mServerKeyBits^[[0m
             Defines the number of bits in the ephemeral protocol version 1
             server key.  The minimum value is 512, and the default is 768.

     ^[[1mStrictModes^[[0m
             Specifies whether ^[[1msshd ^[[22mshould check file modes and ownership of
             the userM-bM-^@M-^Ys files and home directory before accepting login.  This
             is normally desirable because novices sometimes accidentally
             leave their directory or files worldM-bM-^@M-^Pwritable.  The default is
             M-bM-^@M-^\yesM-bM-^@M-^].

     ^[[1mSubsystem^[[0m
             Configures an external subsystem (e.g., file transfer daemon).
             Arguments should be a subsystem name and a command to execute
             upon subsystem request.  The command sftpM-bM-^@M-^Pserver(8) implements
             the M-bM-^@M-^\sftpM-bM-^@M-^] file transfer subsystem.  By default no subsystems are
             defined.  Note that this option applies to protocol version 2
             only.

     ^[[1mSyslogFacility^[[0m
             Gives the facility code that is used when logging messages from
             ^[[1msshd^[[22m.  The possible values are: DAEMON, USER, AUTH, LOCAL0,
             LOCAL1, LOCAL2, LOCAL3, LOCAL4, LOCAL5, LOCAL6, LOCAL7.  The
             default is AUTH.

     ^[[1mUseLogin^[[0m
             Specifies whether login(1) is used for interactive login sesM-bM-^@M-^P
             sions.  The default is M-bM-^@M-^\noM-bM-^@M-^].  Note that login(1) is never used
             for remote command execution.  Note also, that if this is
             enabled, ^[[1mX11Forwarding ^[[22mwill be disabled because login(1) does not
             know how to handle xauth(1) cookies.  If ^[[1mUsePrivilegeSeparation^[[0m
             is specified, it will be disabled after authentication.

     ^[[1mUsePrivilegeSeparation^[[0m
             Specifies whether ^[[1msshd ^[[22mseparates privileges by creating an
             unprivileged child process to deal with incoming network traffic.
             After successful authentication, another process will be created
             that has the privilege of the authenticated user.  The goal of
             privilege separation is to prevent privilege escalation by conM-bM-^@M-^P
             taining any corruption within the unprivileged processes.  The
             default is M-bM-^@M-^\yesM-bM-^@M-^].

     ^[[1mVerifyReverseMapping^[[0m
             Specifies whether ^[[1msshd ^[[22mshould try to verify the remote host name
             and check that the resolved host name for the remote IP address
             maps back to the very same IP address.  The default is M-bM-^@M-^\noM-bM-^@M-^].

     ^[[1mX11DisplayOffset^[[0m
             Specifies the first display number available for ^[[1msshd^[[22mM-bM-^@M-^Ys X11 forM-bM-^@M-^P
             warding.  This prevents ^[[1msshd ^[[22mfrom interfering with real X11
             servers.  The default is 10.

     ^[[1mX11Forwarding^[[0m
             Specifies whether X11 forwarding is permitted.  The argument must
             be M-bM-^@M-^\yesM-bM-^@M-^] or M-bM-^@M-^\noM-bM-^@M-^].  The default is M-bM-^@M-^\noM-bM-^@M-^].

             When X11 forwarding is enabled, there may be additional exposure
             to the server and to client displays if the ^[[1msshd ^[[22mproxy display is
             configured to listen on the wildcard address (see ^[[1mX11UseLocalhost^[[0m
             below), however this is not the default.  Additionally, the
             authentication spoofing and authentication data verification and
             substitution occur on the client side.  The security risk of
             using X11 forwarding is that the clientM-bM-^@M-^Ys X11 display server may
             be exposed to attack when the ssh client requests forwarding (see
             the warnings for ^[[1mForwardX11 ^[[22min ssh_config(5) ). A system adminisM-bM-^@M-^P
             trator may have a stance in which they want to protect clients
             that may expose themselves to attack by unwittingly requesting
             X11 forwarding, which can warrant a M-bM-^@M-^\noM-bM-^@M-^] setting.

             Note that disabling X11 forwarding does not prevent users from
             forwarding X11 traffic, as users can always install their own
             forwarders.  X11 forwarding is automatically disabled if ^[[1mUseLogin^[[0m
             is enabled.

     ^[[1mX11UseLocalhost^[[0m
             Specifies whether ^[[1msshd ^[[22mshould bind the X11 forwarding server to
             the loopback address or to the wildcard address.  By default,
             ^[[1msshd ^[[22mbinds the forwarding server to the loopback address and sets
             the hostname part of the DISPLAY environment variable to
             M-bM-^@M-^\localhostM-bM-^@M-^].  This prevents remote hosts from connecting to the
             proxy display.  However, some older X11 clients may not function
             with this configuration.  ^[[1mX11UseLocalhost ^[[22mmay be set to M-bM-^@M-^\noM-bM-^@M-^] to
             specify that the forwarding server should be bound to the wildM-bM-^@M-^P
             card address.  The argument must be M-bM-^@M-^\yesM-bM-^@M-^] or M-bM-^@M-^\noM-bM-^@M-^].  The default
             is M-bM-^@M-^\yesM-bM-^@M-^].

     ^[[1mXAuthLocation^[[0m
             Specifies the full pathname of the xauth(1) program.  The default
             is ^[[4m/usr/X11R6/bin/xauth^[[24m.

   ^[[1mTime Formats^[[0m

     ^[[1msshd ^[[22mcommandM-bM-^@M-^Pline arguments and configuration file options that specify
     time may be expressed using a sequence of the form: ^[[4mtime^[[24m[^[[4mqualifier^[[24m],
     where ^[[4mtime^[[24m is a positive integer value and ^[[4mqualifier^[[24m is one of the folM-bM-^@M-^P
     lowing:

           ^[[1m<none>  ^[[22mseconds
           ^[[1ms ^[[22m| ^[[1mS   ^[[22mseconds
           ^[[1mm ^[[22m| ^[[1mM   ^[[22mminutes
           ^[[1mh ^[[22m| ^[[1mH   ^[[22mhours
           ^[[1md ^[[22m| ^[[1mD   ^[[22mdays
           ^[[1mw ^[[22m| ^[[1mW   ^[[22mweeks

     Each member of the sequence is added together to calculate the total time
     value.

     Time format examples:

           600     600 seconds (10 minutes)
           10m     10 minutes
           1h30m   1 hour 30 minutes (90 minutes)

^[[1mFILES^[[0m
     /etc/ssh/sshd_config
             Contains configuration data for ^[[1msshd^[[22m.  This file should be
             writable by root only, but it is recommended (though not necesM-bM-^@M-^P
             sary) that it be worldM-bM-^@M-^Preadable.

^[[1mAUTHORS^[[0m
     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, reM-bM-^@M-^Padded newer features and creM-bM-^@M-^P
     ated 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.

^[[1mSEE ALSO^[[0m
     sshd(8)

BSD                           September 25, 1999                           BSD