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.

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