nbdkit-curl-plugin(1)

NAME

   nbdkit-curl-plugin - nbdkit curl plugin (HTTP, FTP, SSH and other
   protocols)

SYNOPSIS

    nbdkit -r curl url=http://example.com/disk.img

    nbdkit -r curl url=sftp://you@example.com/~/disk.img

DESCRIPTION

   "nbdkit-curl-plugin" is a plugin for nbdkit(1) which turns content
   served over HTTP, FTP, SSH, and more, into a Network Block Device.  It
   uses a library called libcurl (also known as cURL) to read data from
   URLs.  The exact list of protocols that libcurl can handle depends on
   how it was compiled, but most versions will handle HTTP, HTTPS, FTP,
   FTPS and SFTP (see: "curl-V").  For more information about libcurl,
   see <http://curl.haxx.se>.

   Note: This plugin supports writes.  However:

   *   For HTTP, you may not want nbdkit to issue PUT requests to the
       remote server (which probably doesn't understand them).

   *   SFTP helpfully truncates the target file when you open it for
       writing.  Not useful!

   To force nbdkit to use a readonly connection, pass the -r flag.

   EXAMPLES
   Basic usage is:

    nbdkit -r curl url=http://example.com/disk.img

   which serves the remote disk image as a NBD on TCP port 10809 (to
   control ports and protocols used to serve NBD see nbdkit(1)).

   You can also access SSH servers.  This uses the SFTP protocol which is
   built into most SSH servers:

    nbdkit -r curl url=sftp://example.com/~/disk.img

   You may need to specify a username and/or a password.  In this example
   the password is read from stdin:

    nbdkit -r curl url=sftp://example.com/~/disk.img username=fred password=-

PARAMETERS

   password=PASSWORD
       Set the password to use when connecting to the remote server.

       Note that passing this on the command line is not secure on shared
       machines.

   password=-
       Ask for the password (interactively) when nbdkit starts up.

   sslverify=0
       Don't verify the SSL certificate of the remote host.

   timeout=SECS
       Set the timeout for requests.

   timeout=0
       Use the default libcurl timeout for requests.

   url=URL
       The URL of the remote disk image.  This is passed to libcurl
       directly via "CURLOPT_URL" in curl_easy_setopt(3).

       This parameter is required.

   user=USERNAME
       Set the username to use when connecting to the remote server.  This
       may also be set in the URL (eg. "http://foo@example.com/disk.img")

SEE ALSO

   curl(1), libcurl(3), nbdkit(1), nbdkit-plugin(3).

AUTHORS

   Richard W.M. Jones

   Parts derived from Alexander Graf's "QEMU Block driver for CURL
   images".

COPYRIGHT

   Copyright (C) 2014 Red Hat Inc.

LICENSE

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions are
   met:

   *   Redistributions of source code must retain the above copyright
       notice, this list of conditions and the following disclaimer.

   *   Redistributions in binary form must reproduce the above copyright
       notice, this list of conditions and the following disclaimer in the
       documentation and/or other materials provided with the
       distribution.

   *   Neither the name of Red Hat nor the names of its contributors may
       be used to endorse or promote products derived from this software
       without specific prior written permission.

   THIS SOFTWARE IS PROVIDED BY RED HAT AND CONTRIBUTORS ''AS IS'' AND ANY
   EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
   PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL RED HAT OR CONTRIBUTORS BE
   LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
   CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
   SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
   BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
   OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
   ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

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