ssh [options] hostname [command]

Securely log a user into a remote system and run commands on that system. The version of ssh described here is the OpenSSH client. ssh can use either Version 1 (SSH1) or Version 2 (SSH2) of the SSH protocol. SSH2 is preferable, as it provides better encryption methods and greater connection integrity. The hostname can be specified either as hostname or as user@hostname. If a command is specified, the user is authenticated, the command is executed, and the connection is closed. Otherwise, a terminal session is opened on the remote system. See later under “Escape characters” for functions that can be supported through an escape character. The default escape character is a tilde (~). The exit status returned from ssh is the exit status from the remote system or 255 if there was an error.



Try only SSH1.


Try only SSH2.


Use only IPv4 addresses.


Use only IPv6 addresses.


Disable forwarding of the authentication agent connection.


Allow forwarding of the authentication agent connection. Can also be specified on a per-host basis in a configuration file.

-b bind_address

Specify the interface to transmit from when there are multiple available interfaces or aliased addresses.

-c blowfish|3des|des|ciphers

Select the cipher for encrypting the session. The default is 3des. For SSH2, a comma-separated list of ciphers can also be specified, with the ciphers listed in order of preference. des is supported only for legacy SSH1 ...

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