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-rw-r--r--ssh_config.570
1 files changed, 65 insertions, 5 deletions
diff --git a/ssh_config.5 b/ssh_config.5
index 95af3976a..585a36878 100644
--- a/ssh_config.5
+++ b/ssh_config.5
@@ -127,8 +127,14 @@ Valid arguments are
127If set to 127If set to
128.Dq yes , 128.Dq yes ,
129passphrase/password querying will be disabled. 129passphrase/password querying will be disabled.
130In addition, the
131.Cm ServerAliveInterval
132and
133.Cm SetupTimeOut
134options will both be set to 300 seconds by default.
130This option is useful in scripts and other batch jobs where no user 135This option is useful in scripts and other batch jobs where no user
131is present to supply the password. 136is present to supply the password,
137and where it is desirable to detect a broken network swiftly.
132The argument must be 138The argument must be
133.Dq yes 139.Dq yes
134or 140or
@@ -447,7 +453,8 @@ token used for the session will be set to expire after 20 minutes.
447Remote clients will be refused access after this time. 453Remote clients will be refused access after this time.
448.Pp 454.Pp
449The default is 455The default is
450.Dq no . 456.Dq yes
457(Debian-specific).
451.Pp 458.Pp
452See the X11 SECURITY extension specification for full details on 459See the X11 SECURITY extension specification for full details on
453the restrictions imposed on untrusted clients. 460the restrictions imposed on untrusted clients.
@@ -477,11 +484,28 @@ Specifies whether user authentication based on GSSAPI is allowed.
477The default is 484The default is
478.Dq no . 485.Dq no .
479Note that this option applies to protocol version 2 only. 486Note that this option applies to protocol version 2 only.
487.It Cm GSSAPIKeyExchange
488Specifies whether key exchange based on GSSAPI may be used. When using
489GSSAPI key exchange the server need not have a host key.
490The default is
491.Dq no .
492Note that this option applies to protocol version 2 only.
480.It Cm GSSAPIDelegateCredentials 493.It Cm GSSAPIDelegateCredentials
481Forward (delegate) credentials to the server. 494Forward (delegate) credentials to the server.
482The default is 495The default is
483.Dq no . 496.Dq no .
484Note that this option applies to protocol version 2 only. 497Note that this option applies to protocol version 2 only.
498.It Cm GSSAPITrustDns
499Set to
500.Dq yes
501to indicate that the DNS is trusted to securely canonicalize
502the name of the host being connected to. If
503.Dq no ,
504the hostname entered on the
505command line will be passed untouched to the GSSAPI library.
506The default is
507.Dq no .
508This option only applies to protocol version 2 connections using GSSAPI.
485.It Cm HashKnownHosts 509.It Cm HashKnownHosts
486Indicates that 510Indicates that
487.Xr ssh 1 511.Xr ssh 1
@@ -499,6 +523,9 @@ Note that existing names and addresses in known hosts files
499will not be converted automatically, 523will not be converted automatically,
500but may be manually hashed using 524but may be manually hashed using
501.Xr ssh-keygen 1 . 525.Xr ssh-keygen 1 .
526Use of this option may break facilities such as tab-completion that rely
527on being able to read unhashed host names from
528.Pa ~/.ssh/known_hosts .
502.It Cm HostbasedAuthentication 529.It Cm HostbasedAuthentication
503Specifies whether to try rhosts based authentication with public key 530Specifies whether to try rhosts based authentication with public key
504authentication. 531authentication.
@@ -630,7 +657,7 @@ indicates that the port should be available from all interfaces.
630Gives the verbosity level that is used when logging messages from 657Gives the verbosity level that is used when logging messages from
631.Xr ssh 1 . 658.Xr ssh 1 .
632The possible values are: 659The possible values are:
633QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3. 660SILENT, QUIET, FATAL, ERROR, INFO, VERBOSE, DEBUG, DEBUG1, DEBUG2, and DEBUG3.
634The default is INFO. 661The default is INFO.
635DEBUG and DEBUG1 are equivalent. 662DEBUG and DEBUG1 are equivalent.
636DEBUG2 and DEBUG3 each specify higher levels of verbose output. 663DEBUG2 and DEBUG3 each specify higher levels of verbose output.
@@ -876,7 +903,10 @@ If, for example,
876.Cm ServerAliveCountMax 903.Cm ServerAliveCountMax
877is left at the default, if the server becomes unresponsive, 904is left at the default, if the server becomes unresponsive,
878ssh will disconnect after approximately 45 seconds. 905ssh will disconnect after approximately 45 seconds.
879This option applies to protocol version 2 only. 906This option applies to protocol version 2 only; in protocol version
9071 there is no mechanism to request a response from the server to the
908server alive messages, so disconnection is the responsibility of the TCP
909stack.
880.It Cm ServerAliveInterval 910.It Cm ServerAliveInterval
881Sets a timeout interval in seconds after which if no data has been received 911Sets a timeout interval in seconds after which if no data has been received
882from the server, 912from the server,
@@ -884,8 +914,30 @@ from the server,
884will send a message through the encrypted 914will send a message through the encrypted
885channel to request a response from the server. 915channel to request a response from the server.
886The default 916The default
887is 0, indicating that these messages will not be sent to the server. 917is 0, indicating that these messages will not be sent to the server,
918or 300 if the
919.Cm BatchMode
920option is set.
888This option applies to protocol version 2 only. 921This option applies to protocol version 2 only.
922.Cm ProtocolKeepAlives
923is a Debian-specific compatibility alias for this option.
924.It Cm SetupTimeOut
925Normally,
926.Nm ssh
927blocks indefinitely whilst waiting to receive the ssh banner and other
928setup protocol from the server, during the session setup.
929This can cause
930.Nm ssh
931to hang under certain circumstances.
932If this option is set,
933.Nm ssh
934will give up if no data from the server is received for the specified
935number of seconds.
936The argument must be an integer.
937The default is 0 (disabled), or 300 if
938.Cm BatchMode
939is set.
940This is a Debian-specific option.
889.It Cm SmartcardDevice 941.It Cm SmartcardDevice
890Specifies which smartcard device to use. 942Specifies which smartcard device to use.
891The argument to this keyword is the device 943The argument to this keyword is the device
@@ -931,6 +983,12 @@ Specifies whether the system should send TCP keepalive messages to the
931other side. 983other side.
932If they are sent, death of the connection or crash of one 984If they are sent, death of the connection or crash of one
933of the machines will be properly noticed. 985of the machines will be properly noticed.
986This option only uses TCP keepalives (as opposed to using ssh level
987keepalives), so takes a long time to notice when the connection dies.
988As such, you probably want
989the
990.Cm ServerAliveInterval
991option as well.
934However, this means that 992However, this means that
935connections will die if the route is down temporarily, and some people 993connections will die if the route is down temporarily, and some people
936find it annoying. 994find it annoying.
@@ -1086,6 +1144,8 @@ The format of this file is described above.
1086This file is used by the SSH client. 1144This file is used by the SSH client.
1087Because of the potential for abuse, this file must have strict permissions: 1145Because of the potential for abuse, this file must have strict permissions:
1088read/write for the user, and not accessible by others. 1146read/write for the user, and not accessible by others.
1147It may be group-writable provided that the group in question contains only
1148the user.
1089.It Pa /etc/ssh/ssh_config 1149.It Pa /etc/ssh/ssh_config
1090Systemwide configuration file. 1150Systemwide configuration file.
1091This file provides defaults for those 1151This file provides defaults for those