Provided by: nbdkit_1.16.2-1ubuntu3_amd64
nbdkit-curl-plugin - nbdkit curl plugin (HTTP, FTP and other protocols)
nbdkit -r curl [url=]http://example.com/disk.img
"nbdkit-curl-plugin" is a plugin for nbdkit(1) which turns content served over HTTP, FTP, 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 more (see: "curl -V"). 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). To force nbdkit to use a readonly connection, pass the -r flag. Although this plugin can access SFTP (ie. SSH) servers, it is much better to use nbdkit-ssh-plugin(1).
nbdkit -r curl http://example.com/disk.img serves the remote disk image as NBD on TCP port 10809 (to control ports and protocols used to serve NBD see nbdkit(1)).
cookie=COOKIE cookie=+FILENAME Set a cookie in the request header when connecting to the remote server. A typical example is: cookie='vmware_soap_session="52a01262-bf93-ccce-d379-8dabb3e55560"' This option can be used at most once. It only works for HTTP and HTTPS transports. To set multiple cookies you must concatenate them yourself, eg: cookie='name1=content1; name2=content2;' See CURLOPT_COOKIE(3) for more information about this. If the cookie is used for authentication then passing it on the command line is not secure on shared machines. Use the alternate "+FILENAME" syntax to pass it in a file. 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. password=+FILENAME Read the password from the named file. This is a secure method to supply a password, as long as you set the permissions on the file appropriately. password=-FD Read the password from file descriptor number "FD", inherited from the parent process when nbdkit starts up. This is also a secure method to supply a password. protocols=PROTO,PROTO,... Limit the protocols that are allowed in the URL. Use this option for extra security if the URL comes from an untrusted source and you want to avoid security isues in the more obscure protocols that curl supports. (See qemu CVE-2013-0249 for an example of a security bug introduced by allowing unrestricted protocols). For example if you only intend HTTP and HTTPS URLs to be used, then add this parameter: "protocols=http,https" The value of this parameter is a comma-separated list of protocols. The following protocols are known: dict, file, ftp, ftps, gopher, http, https, imap, imaps, ldap, ldaps, pop3, pop3s, rtmp, rtmpe, rtmps, rtmpt, rtmpte, rtmpts, rtsp, scp, sftp, smb, smbs, smtp, smtps, telnet, tftp. The default is to allow any protocol. proxy-password=PASSWORD proxy-password=- proxy-password=+FILENAME proxy-password=-FD proxy-user=USERNAME Set the proxy username and password. sslverify=false 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. unix-socket-path=PATH Instead of using a TCP connection, connect to the server over the named Unix domain socket. See "CURLOPT_UNIX_SOCKET_PATH" in curl_easy_setopt(3). [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. "url=" is a magic config key and may be omitted in most cases. See "Magic parameters" in nbdkit(1). user=USERNAME Set the username to use when connecting to the remote server. This may also be set in the URL (eg. "http://email@example.com/disk.img")
-D curl.verbose=1 This enables very verbose curl debugging. See CURLOPT_VERBOSE(3). This is mainly useful if you suspect there is a bug inside libcurl itself.
$plugindir/nbdkit-curl-plugin.so The plugin. Use "nbdkit --dump-config" to find the location of $plugindir.
"nbdkit-curl-plugin" first appeared in nbdkit 1.2.
curl(1), libcurl(3), CURLOPT_COOKIE(3) CURLOPT_VERBOSE(3), nbdkit(1), nbdkit-readahead-filter(1), nbdkit-retry-filter(1), nbdkit-ssh-plugin(1), nbdkit-plugin(3), http://curl.haxx.se.
Richard W.M. Jones Parts derived from Alexander Graf's "QEMU Block driver for CURL images".
Copyright (C) 2014 Red Hat Inc.
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