+If the nbd-server uses named exports (since NBD 2.9.18), you must use the
+"exportname" option:
+@example
+qemu -cdrom nbd:localhost:exportname=debian-500-ppc-netinst
+qemu -cdrom nbd:localhost:exportname=openSUSE-11.1-ppc-netinst
+@end example
+
+@node disk_images_sheepdog
+@subsection Sheepdog disk images
+
+Sheepdog is a distributed storage system for QEMU. It provides highly
+available block level storage volumes that can be attached to
+QEMU-based virtual machines.
+
+You can create a Sheepdog disk image with the command:
+@example
+qemu-img create sheepdog:@var{image} @var{size}
+@end example
+where @var{image} is the Sheepdog image name and @var{size} is its
+size.
+
+To import the existing @var{filename} to Sheepdog, you can use a
+convert command.
+@example
+qemu-img convert @var{filename} sheepdog:@var{image}
+@end example
+
+You can boot from the Sheepdog disk image with the command:
+@example
+qemu sheepdog:@var{image}
+@end example
+
+You can also create a snapshot of the Sheepdog image like qcow2.
+@example
+qemu-img snapshot -c @var{tag} sheepdog:@var{image}
+@end example
+where @var{tag} is a tag name of the newly created snapshot.
+
+To boot from the Sheepdog snapshot, specify the tag name of the
+snapshot.
+@example
+qemu sheepdog:@var{image}:@var{tag}
+@end example
+
+You can create a cloned image from the existing snapshot.
+@example
+qemu-img create -b sheepdog:@var{base}:@var{tag} sheepdog:@var{image}
+@end example
+where @var{base} is a image name of the source snapshot and @var{tag}
+is its tag name.
+
+If the Sheepdog daemon doesn't run on the local host, you need to
+specify one of the Sheepdog servers to connect to.
+@example
+qemu-img create sheepdog:@var{hostname}:@var{port}:@var{image} @var{size}
+qemu sheepdog:@var{hostname}:@var{port}:@var{image}
+@end example
+
+@node disk_images_iscsi
+@subsection iSCSI LUNs
+
+iSCSI is a popular protocol used to access SCSI devices across a computer
+network.
+
+There are two different ways iSCSI devices can be used by QEMU.
+
+The first method is to mount the iSCSI LUN on the host, and make it appear as
+any other ordinary SCSI device on the host and then to access this device as a
+/dev/sd device from QEMU. How to do this differs between host OSes.
+
+The second method involves using the iSCSI initiator that is built into
+QEMU. This provides a mechanism that works the same way regardless of which
+host OS you are running QEMU on. This section will describe this second method
+of using iSCSI together with QEMU.
+
+In QEMU, iSCSI devices are described using special iSCSI URLs
+
+@example
+URL syntax:
+iscsi://[<username>[%<password>]@@]<host>[:<port>]/<target-iqn-name>/<lun>
+@end example
+
+Username and password are optional and only used if your target is set up
+using CHAP authentication for access control.
+Alternatively the username and password can also be set via environment
+variables to have these not show up in the process list
+
+@example
+export LIBISCSI_CHAP_USERNAME=<username>
+export LIBISCSI_CHAP_PASSWORD=<password>
+iscsi://<host>/<target-iqn-name>/<lun>
+@end example
+
+Various session related parameters can be set via special options, either
+in a configuration file provided via '-readconfig' or directly on the
+command line.
+
+@example
+Setting a specific initiator name to use when logging in to the target
+-iscsi initiator-name=iqn.qemu.test:my-initiator
+@end example
+
+@example
+Controlling which type of header digest to negotiate with the target
+-iscsi header-digest=CRC32C|CRC32C-NONE|NONE-CRC32C|NONE
+@end example
+
+These can also be set via a configuration file
+@example
+[iscsi]
+ user = "CHAP username"
+ password = "CHAP password"
+ initiator-name = "iqn.qemu.test:my-initiator"
+ # header digest is one of CRC32C|CRC32C-NONE|NONE-CRC32C|NONE
+ header-digest = "CRC32C"
+@end example
+
+
+Setting the target name allows different options for different targets
+@example
+[iscsi "iqn.target.name"]
+ user = "CHAP username"
+ password = "CHAP password"
+ initiator-name = "iqn.qemu.test:my-initiator"
+ # header digest is one of CRC32C|CRC32C-NONE|NONE-CRC32C|NONE
+ header-digest = "CRC32C"
+@end example
+
+
+Howto use a configuration file to set iSCSI configuration options:
+@example
+cat >iscsi.conf <<EOF
+[iscsi]
+ user = "me"
+ password = "my password"
+ initiator-name = "iqn.qemu.test:my-initiator"
+ header-digest = "CRC32C"
+EOF
+
+qemu-system-i386 -drive file=iscsi://127.0.0.1/iqn.qemu.test/1 \
+ -readconfig iscsi.conf
+@end example
+
+
+Howto set up a simple iSCSI target on loopback and accessing it via QEMU:
+@example
+This example shows how to set up an iSCSI target with one CDROM and one DISK
+using the Linux STGT software target. This target is available on Red Hat based
+systems as the package 'scsi-target-utils'.
+
+tgtd --iscsi portal=127.0.0.1:3260
+tgtadm --lld iscsi --op new --mode target --tid 1 -T iqn.qemu.test
+tgtadm --lld iscsi --mode logicalunit --op new --tid 1 --lun 1 \
+ -b /IMAGES/disk.img --device-type=disk
+tgtadm --lld iscsi --mode logicalunit --op new --tid 1 --lun 2 \
+ -b /IMAGES/cd.iso --device-type=cd
+tgtadm --lld iscsi --op bind --mode target --tid 1 -I ALL
+
+qemu-system-i386 -iscsi initiator-name=iqn.qemu.test:my-initiator \
+ -boot d -drive file=iscsi://127.0.0.1/iqn.qemu.test/1 \
+ -cdrom iscsi://127.0.0.1/iqn.qemu.test/2
+@end example
+
+
+
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