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NAME

       dbclient - lightweight SSH2 client

SYNOPSIS

       dbclient  [-Tt]  [-p port] [-i id] [-L l:h:r] [-R l:h:r] [-l user] host
       [command]

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

DESCRIPTION

       dbclient is a SSH 2 client designed to be small enough to  be  used  in
       small  memory  environments,  while  still  being functional and secure
       enough for general use.

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

OPTIONS

       -p port
              Remote  port.  Connect to port port on the remote host.  Default
              is 22.

       -i idfile
              Identity file.  Read the identity  from  file  idfile  (multiple
              allowed).

       -L 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 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.

       -T     Don’t allocate a pty.

       -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.

       -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.

       -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.

              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 slash (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.

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.

AUTHOR

       Matt Johnston (matt@ucc.asn.au).
       Mihnea Stoenescu wrote initial Dropbear client support
       Gerrit Pape (pape@smarden.org) wrote this manual page.

SEE ALSO

       dropbear(8), dropbearkey(8)

       http://matt.ucc.asn.au/dropbear/dropbear.html

                                                                   dbclient(1)