dbclient - Online in the Cloud

PROGRAM:

NAME

dbclient - lightweight SSH client

SYNOPSIS

dbclient [flag arguments] [-p port] [-i id] [-L l:h:p] [-R l:h:p] [-l user] host
[more flags] [command]

dbclient [args] [user1]@host1[^port1],[user2]@host2[^port2],...

DESCRIPTION

dbclient is a small SSH client

OPTIONS

command
A command to run on the remote host. This will normally be run by the remote host
using the user's shell. The command begins at the first hyphen argument after the
host argument. If no command is specified an interactive terminal will be opened
(see -t and -T).

-p port
Connect to port on the remote host. Alternatively a port can be specified as
hostname^port. Default is 22.

-i idfile
Identity file. Read the identity key from file idfile (multiple allowed). This
file is created with dropbearkey(1) or converted from OpenSSH with
dropbearconvert(1). The default path ~/.ssh/id_dropbear is used

-L [listenaddress]:listenport:host:port
Local port forwarding. Forward the port listenport on the local host through the
SSH connection to port port on the host host.

-R [listenaddress]:listenport:host:port
Remote port forwarding. Forward the port listenport on the remote host through the
SSH connection to port port on the host host.

-l user
Username. Login as user on the remote host.

-t Allocate a PTY. This is the default when no command is given, it gives a full
interactive remote session. The main effect is that keystrokes are sent remotely
immediately as opposed to local line-based editing.

-T Don't allocate a PTY. This is the default a command is given. See -t.

-N Don't request a remote shell or run any commands. Any command arguments are
ignored.

-f Fork into the background after authentication. A command argument (or -N) is
required. This is useful when using password authentication.

-g Allow non-local hosts to connect to forwarded ports. Applies to -L and -R forwarded
ports, though remote connections to -R forwarded ports may be limited by the ssh
server.

-y Always accept hostkeys if they are unknown. If a hostkey mismatch occurs the
connection will abort as normal. If specified a second time no host key checking is
performed at all, this is usually undesirable.

-A Forward agent connections to the remote host. dbclient will use any OpenSSH-style
agent program if available ($SSH_AUTH_SOCK will be set) for public key
authentication. Forwarding is only enabled if -A is specified.

-W windowsize
Specify the per-channel receive window buffer size. Increasing this may improve
network performance at the expense of memory use. Use -h to see the default buffer
size.

-K timeout_seconds
Ensure that traffic is transmitted at a certain interval in seconds. This is useful
for working around firewalls or routers that drop connections after a certain
period of inactivity. The trade-off is that a session may be closed if there is a
temporary lapse of network connectivity. A setting if 0 disables keepalives. If no
response is received for 3 consecutive keepalives the connection will be closed.

-I idle_timeout
Disconnect the session if no traffic is transmitted or received for idle_timeout
seconds.

-J proxy_command
Use the standard input/output of the program proxy_command rather than using a
normal TCP connection. A hostname should be still be provided, as this is used for
comparing saved hostkeys.

-B endhost:endport
"Netcat-alike" mode, where Dropbear will connect to the given host, then create a
forwarded connection to endhost. This will then be presented as dbclient's standard
input/output.

-c cipherlist
Specify a comma separated list of ciphers to enable. Use -c help to list
possibilities.

-m MAClist
Specify a comma separated list of authentication MACs to enable. Use -m help to
list possibilities.

-s The specified command will be requested as a subsystem, used for sftp. Dropbear
doesn't implement sftp itself but the OpenSSH sftp client can be used eg sftp -S
dbclient user@host

-V Print the version

MULTI-HOP

Dropbear will also allow multiple "hops" to be specified, separated by commas. In this
case a connection will be made to the first host, then a TCP forwarded connection will be
made through that to the second host, and so on. Hosts other than the final destination
will not see anything other than the encrypted SSH stream. A port for a host can be
specified with a caret (eg matt@martello^44 ). This syntax can also be used with scp or
rsync (specifying dbclient as the ssh/rsh command). A file can be "bounced" through
multiple SSH hops, eg

scp -S dbclient matt@martello,root@wrt,canyons:/tmp/dump .

Note that hostnames are resolved by the prior hop (so "canyons" would be resolved by the
host "wrt") in the example above, the same way as other -L TCP forwarded hosts are. Host
keys are checked locally based on the given hostname.

ESCAPE CHARACTERS

Typing a newline followed by the key sequence ~. (tilde, dot) will terminate a
connection. The sequence ~^Z (tilde, ctrl-z) will background the connection. This
behaviour only applies when a PTY is used.

ENVIRONMENT

DROPBEAR_PASSWORD
A password to use for remote authentication can be specified in the environment
variable DROPBEAR_PASSWORD. Care should be taken that the password is not exposed
to other users on a multi-user system, or stored in accessible files.

SSH_ASKPASS
dbclient can use an external program to request a password from a user.
SSH_ASKPASS should be set to the path of a program that will return a password on
standard output. This program will only be used if either DISPLAY is set and
standard input is not a TTY, or the environment variable SSH_ASKPASS_ALWAYS is set.

NOTES

If compiled with zlib support and if the server supports it, dbclient will always use
compression.

Use dbclient online using onworks.net services