Silver Peak Command Line Interface Reference Guide
Copyright © 2019 by Silver Peak Systems, Inc. All rights reserved
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-m
mac_spec
: Additionally, for protocol version 2 a comma-separated
list of MAC (message authentication code) algorithms can be
specified in order of preference.
-n Redirects stdin from /dev/null (actually, prevents reading from stdin).
This must be used when ssh is run in the background. A common trick
is to use this to run X11 programs on a remote machine. For example,
ssh -n shadows.cs.hut.fi emacs and will start an emacs on
shadows.cs.hut.fi, and the X11 connection will be automatically
forwarded over an encrypted channel. The ssh program will be put in
the background. (This does not work if ssh needs to ask for a
password or passphrase; see also the -f option.)
-N
Do not execute a remote command. This is useful for just forwarding
ports (protocol version 2 only).
-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.
-p
port
: Port to connect to on the remote host. This can be specified on a
per-host basis in the configuration file.
-q
Quiet mode
. Causes all warning and diagnostic messages to be
suppressed.
-s
May be used to request invocation of a subsystem on the remote
system. Subsystems are a feature of the SSH2 protocol which
facilitate the use of SSH as a secure transport for other applications
(for example, sftp). The subsystem is specified as the remote
command.
-t
Force pseudo-tty allocation. This can be used to execute arbitrary
screen-based programs on a remote machine, which can be very
useful, for example, when implementing menu services. Multiple -t
options force tty allocation, even if ssh has no local tty.
-T
Disable pseudo-tty allocation.
-v
Verbose mode
. Causes ssh to print debugging messages about its
progress. This is helpful in debugging connection, authentication, and
configuration problems. Multiple -v options increases the verbosity.
Maximum is 3.
-V
Display the version number and exit.
-x
Disables X11 forwarding.
-X
Enables X11 forwarding. This can also be specified on a per-host
basis in a configuration file. X11 forwarding should be enabled with
caution. Users with the ability to bypass file permissions on the
remote host (for the user’s X authorization database) can access the
local X11 display through the forwarded connection. An attacker may
then be able to perform activities such as keystroke monitoring.
-Y
Enables trusted X11 forwarding. Trusted X11 forwardings are not
subjected to the X11 SECURITY extension controls.
-C
Requests compression of all data (including stdin, stdout, stderr, and
data for forwarded X11 and TCP/IP connections). The compression
algorithm is the same used by gzip(1), and the
level
CompressionLevel option for protocol version 1. Compression is
desirable on modem lines and other slow connections, but will only
slow down things on fast networks. The default value can be set on a
host-by-host basis in the configuration files.