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|
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
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