1dbclient(1)                 General Commands Manual                dbclient(1)
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NAME

6       dbclient - lightweight SSH2 client
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SYNOPSIS

9       dbclient  [-Tt]  [-p port] [-i id] [-L l:h:r] [-R l:h:r] [-l user] host
10       [command]
11
12       dbclient [ args ] [user1]@host1[/port1],[user2]@host2[/port2],...
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14

DESCRIPTION

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

21       -p port
22              Remote port.  Connect to port port on the remote host.   Default
23              is 22.
24
25       -i idfile
26              Identity  file.   Read  the  identity from file idfile (multiple
27              allowed).
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29       -L listenport:host:port
30              Local port forwarding.  Forward the port listenport on the local
31              host through the SSH connection to port port on the host host.
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33       -R listenport:host:port
34              Remote  port  forwarding.   Forward  the  port listenport on the
35              remote host through the SSH connection to port port on the  host
36              host.
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38       -l user
39              Username.  Login as user on the remote host.
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41       -t     Allocate a pty.
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43       -T     Don't allocate a pty.
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45       -N     Don't  request  a  remote shell or run any commands. Any command
46              arguments are ignored.
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48       -f     Fork into the background after authentication. A  command  argu‐
49              ment  (or  -N)  is required.  This is useful when using password
50              authentication.
51
52       -g     Allow non-local hosts to connect to forwarded ports. Applies  to
53              -L  and -R forwarded ports, though remote connections to -R for‐
54              warded ports may be limited by the ssh server.
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56       -y     Always accept hostkeys if they are unknown. If  a  hostkey  mis‐
57              match occurs the connection will abort as normal.
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59       -W windowsize
60              Specify  the  per-channel receive window buffer size. Increasing
61              this may improve network performance at the  expense  of  memory
62              use. Use -h to see the default buffer size.
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64       -K timeout_seconds
65              Ensure that traffic is transmitted at a certain interval in sec‐
66              onds. This is useful for working  around  firewalls  or  routers
67              that  drop connections after a certain period of inactivity. The
68              trade-off is that a session may be closed if there is  a  tempo‐
69              rary  lapse  of  network  connectivity.  A setting if 0 disables
70              keepalives.
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72       -I idle_timeout
73              Disconnect the session if no traffic is transmitted or  received
74              for idle_timeout seconds.
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76       -J proxy_command
77              Use  the  standard  input/output  of  the  program proxy_command
78              rather than using a normal TCP connection. A hostname should  be
79              still be provided, as this is used for comparing saved hostkeys.
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81       -B endhost:endport
82              "Netcat-alike"  mode,  where  Dropbear will connect to the given
83              host, then create a forwarded connection to endhost.  This  will
84              then be presented as dbclient's standard input/output.
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86              Dropbear  will also allow multiple "hops" to be specified, sepa‐
87              rated by commas. In this case a connection will be made  to  the
88              first host, then a TCP forwarded connection will be made through
89              that to the second host, and so on. Hosts other than  the  final
90              destination  will  not see anything other than the encrypted SSH
91              stream.  A port for a host can be specified  with  a  slash  (eg
92              matt@martello/44  ).   This  syntax can also be used with scp or
93              rsync (specifying dbclient as the ssh/rsh command). A  file  can
94              be "bounced" through multiple SSH hops, eg
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96              scp -S dbclient matt@martello,root@wrt,canyons:/tmp/dump .
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98              Note  that hostnames are resolved by the prior hop (so "canyons"
99              would be resolved by the host "wrt") in the example  above,  the
100              same  way  as  other  -L  TCP forwarded hosts are. Host keys are
101              checked locally based on the given hostname.
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103

ENVIRONMENT

105       DROPBEAR_PASSWORD
106              A password to use for remote authentication can be specified  in
107              the environment variable DROPBEAR_PASSWORD. Care should be taken
108              that the password is not exposed to other users on a  multi-user
109              system, or stored in accessible files.
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111       SSH_ASKPASS
112              dbclient  can use an external program to request a password from
113              a user.  SSH_ASKPASS should be set to the path of a program that
114              will  return  a  password  on standard output. This program will
115              only be used if either DISPLAY is set and standard input is  not
116              a TTY, or the environment variable SSH_ASKPASS_ALWAYS is set.
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AUTHOR

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

124       dropbear(8), dropbearkey(8)
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126       http://matt.ucc.asn.au/dropbear/dropbear.html
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