mirror of
https://github.com/qemu/qemu.git
synced 2024-12-18 01:34:15 +08:00
09ec85176e
It was deprecated in commit e1c4269763, v5.2.0. See that commit
message for rationale.
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20210501075747.3293186-1-armbru@redhat.com>
ACKed-by: Peter Krempa <pkrempa@redhat.com>
211 lines
7.9 KiB
PHP
211 lines
7.9 KiB
PHP
|
||
In addition to using normal file images for the emulated storage
|
||
devices, QEMU can also use networked resources such as iSCSI devices.
|
||
These are specified using a special URL syntax.
|
||
|
||
``iSCSI``
|
||
iSCSI support allows QEMU to access iSCSI resources directly and use
|
||
as images for the guest storage. Both disk and cdrom images are
|
||
supported.
|
||
|
||
Syntax for specifying iSCSI LUNs is
|
||
"iscsi://<target-ip>[:<port>]/<target-iqn>/<lun>"
|
||
|
||
By default qemu will use the iSCSI initiator-name
|
||
'iqn.2008-11.org.linux-kvm[:<name>]' but this can also be set from
|
||
the command line or a configuration file.
|
||
|
||
Since version Qemu 2.4 it is possible to specify a iSCSI request
|
||
timeout to detect stalled requests and force a reestablishment of the
|
||
session. The timeout is specified in seconds. The default is 0 which
|
||
means no timeout. Libiscsi 1.15.0 or greater is required for this
|
||
feature.
|
||
|
||
Example (without authentication):
|
||
|
||
.. parsed-literal::
|
||
|
||
|qemu_system| -iscsi initiator-name=iqn.2001-04.com.example:my-initiator \\
|
||
-cdrom iscsi://192.0.2.1/iqn.2001-04.com.example/2 \\
|
||
-drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
|
||
|
||
Example (CHAP username/password via URL):
|
||
|
||
.. parsed-literal::
|
||
|
||
|qemu_system| -drive file=iscsi://user%password@192.0.2.1/iqn.2001-04.com.example/1
|
||
|
||
Example (CHAP username/password via environment variables):
|
||
|
||
.. parsed-literal::
|
||
|
||
LIBISCSI_CHAP_USERNAME="user" \\
|
||
LIBISCSI_CHAP_PASSWORD="password" \\
|
||
|qemu_system| -drive file=iscsi://192.0.2.1/iqn.2001-04.com.example/1
|
||
|
||
``NBD``
|
||
QEMU supports NBD (Network Block Devices) both using TCP protocol as
|
||
well as Unix Domain Sockets. With TCP, the default port is 10809.
|
||
|
||
Syntax for specifying a NBD device using TCP, in preferred URI form:
|
||
"nbd://<server-ip>[:<port>]/[<export>]"
|
||
|
||
Syntax for specifying a NBD device using Unix Domain Sockets;
|
||
remember that '?' is a shell glob character and may need quoting:
|
||
"nbd+unix:///[<export>]?socket=<domain-socket>"
|
||
|
||
Older syntax that is also recognized:
|
||
"nbd:<server-ip>:<port>[:exportname=<export>]"
|
||
|
||
Syntax for specifying a NBD device using Unix Domain Sockets
|
||
"nbd:unix:<domain-socket>[:exportname=<export>]"
|
||
|
||
Example for TCP
|
||
|
||
.. parsed-literal::
|
||
|
||
|qemu_system| --drive file=nbd:192.0.2.1:30000
|
||
|
||
Example for Unix Domain Sockets
|
||
|
||
.. parsed-literal::
|
||
|
||
|qemu_system| --drive file=nbd:unix:/tmp/nbd-socket
|
||
|
||
``SSH``
|
||
QEMU supports SSH (Secure Shell) access to remote disks.
|
||
|
||
Examples:
|
||
|
||
.. parsed-literal::
|
||
|
||
|qemu_system| -drive file=ssh://user@host/path/to/disk.img
|
||
|qemu_system| -drive file.driver=ssh,file.user=user,file.host=host,file.port=22,file.path=/path/to/disk.img
|
||
|
||
Currently authentication must be done using ssh-agent. Other
|
||
authentication methods may be supported in future.
|
||
|
||
``GlusterFS``
|
||
GlusterFS is a user space distributed file system. QEMU supports the
|
||
use of GlusterFS volumes for hosting VM disk images using TCP, Unix
|
||
Domain Sockets and RDMA transport protocols.
|
||
|
||
Syntax for specifying a VM disk image on GlusterFS volume is
|
||
|
||
.. parsed-literal::
|
||
|
||
URI:
|
||
gluster[+type]://[host[:port]]/volume/path[?socket=...][,debug=N][,logfile=...]
|
||
|
||
JSON:
|
||
'json:{"driver":"qcow2","file":{"driver":"gluster","volume":"testvol","path":"a.img","debug":N,"logfile":"...",
|
||
"server":[{"type":"tcp","host":"...","port":"..."},
|
||
{"type":"unix","socket":"..."}]}}'
|
||
|
||
Example
|
||
|
||
.. parsed-literal::
|
||
|
||
URI:
|
||
|qemu_system| --drive file=gluster://192.0.2.1/testvol/a.img,
|
||
file.debug=9,file.logfile=/var/log/qemu-gluster.log
|
||
|
||
JSON:
|
||
|qemu_system| 'json:{"driver":"qcow2",
|
||
"file":{"driver":"gluster",
|
||
"volume":"testvol","path":"a.img",
|
||
"debug":9,"logfile":"/var/log/qemu-gluster.log",
|
||
"server":[{"type":"tcp","host":"1.2.3.4","port":24007},
|
||
{"type":"unix","socket":"/var/run/glusterd.socket"}]}}'
|
||
|qemu_system| -drive driver=qcow2,file.driver=gluster,file.volume=testvol,file.path=/path/a.img,
|
||
file.debug=9,file.logfile=/var/log/qemu-gluster.log,
|
||
file.server.0.type=tcp,file.server.0.host=1.2.3.4,file.server.0.port=24007,
|
||
file.server.1.type=unix,file.server.1.socket=/var/run/glusterd.socket
|
||
|
||
See also http://www.gluster.org.
|
||
|
||
``HTTP/HTTPS/FTP/FTPS``
|
||
QEMU supports read-only access to files accessed over http(s) and
|
||
ftp(s).
|
||
|
||
Syntax using a single filename:
|
||
|
||
::
|
||
|
||
<protocol>://[<username>[:<password>]@]<host>/<path>
|
||
|
||
where:
|
||
|
||
``protocol``
|
||
'http', 'https', 'ftp', or 'ftps'.
|
||
|
||
``username``
|
||
Optional username for authentication to the remote server.
|
||
|
||
``password``
|
||
Optional password for authentication to the remote server.
|
||
|
||
``host``
|
||
Address of the remote server.
|
||
|
||
``path``
|
||
Path on the remote server, including any query string.
|
||
|
||
The following options are also supported:
|
||
|
||
``url``
|
||
The full URL when passing options to the driver explicitly.
|
||
|
||
``readahead``
|
||
The amount of data to read ahead with each range request to the
|
||
remote server. This value may optionally have the suffix 'T', 'G',
|
||
'M', 'K', 'k' or 'b'. If it does not have a suffix, it will be
|
||
assumed to be in bytes. The value must be a multiple of 512 bytes.
|
||
It defaults to 256k.
|
||
|
||
``sslverify``
|
||
Whether to verify the remote server's certificate when connecting
|
||
over SSL. It can have the value 'on' or 'off'. It defaults to
|
||
'on'.
|
||
|
||
``cookie``
|
||
Send this cookie (it can also be a list of cookies separated by
|
||
';') with each outgoing request. Only supported when using
|
||
protocols such as HTTP which support cookies, otherwise ignored.
|
||
|
||
``timeout``
|
||
Set the timeout in seconds of the CURL connection. This timeout is
|
||
the time that CURL waits for a response from the remote server to
|
||
get the size of the image to be downloaded. If not set, the
|
||
default timeout of 5 seconds is used.
|
||
|
||
Note that when passing options to qemu explicitly, ``driver`` is the
|
||
value of <protocol>.
|
||
|
||
Example: boot from a remote Fedora 20 live ISO image
|
||
|
||
.. parsed-literal::
|
||
|
||
|qemu_system_x86| --drive media=cdrom,file=https://archives.fedoraproject.org/pub/archive/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
|
||
|
||
|qemu_system_x86| --drive media=cdrom,file.driver=http,file.url=http://archives.fedoraproject.org/pub/fedora/linux/releases/20/Live/x86_64/Fedora-Live-Desktop-x86_64-20-1.iso,readonly
|
||
|
||
Example: boot from a remote Fedora 20 cloud image using a local
|
||
overlay for writes, copy-on-read, and a readahead of 64k
|
||
|
||
.. parsed-literal::
|
||
|
||
qemu-img create -f qcow2 -o backing_file='json:{"file.driver":"http",, "file.url":"http://archives.fedoraproject.org/pub/archive/fedora/linux/releases/20/Images/x86_64/Fedora-x86_64-20-20131211.1-sda.qcow2",, "file.readahead":"64k"}' /tmp/Fedora-x86_64-20-20131211.1-sda.qcow2
|
||
|
||
|qemu_system_x86| -drive file=/tmp/Fedora-x86_64-20-20131211.1-sda.qcow2,copy-on-read=on
|
||
|
||
Example: boot from an image stored on a VMware vSphere server with a
|
||
self-signed certificate using a local overlay for writes, a readahead
|
||
of 64k and a timeout of 10 seconds.
|
||
|
||
.. parsed-literal::
|
||
|
||
qemu-img create -f qcow2 -o backing_file='json:{"file.driver":"https",, "file.url":"https://user:password@vsphere.example.com/folder/test/test-flat.vmdk?dcPath=Datacenter&dsName=datastore1",, "file.sslverify":"off",, "file.readahead":"64k",, "file.timeout":10}' /tmp/test.qcow2
|
||
|
||
|qemu_system_x86| -drive file=/tmp/test.qcow2
|