Red Hat Bugzilla – Bug 962113
Disable libguestfs block drivers which are not supported by RHEL 7 qemu + libvirt
Last modified: 2014-06-17 21:59:38 EDT
Description of problem:
Upstream libguestfs now supports many of upstream qemu's block
drivers. Currently that list is:
Some of these will not be supported in qemu. Some are not
supported by libvirt (not even upstream libvirt).
We need to find out which will be supported in qemu + libvirt
in RHEL 7, and limit the devices to just those. The others would
be removed from the documentation (and implementation?) in
libguestfs in RHEL 7.
Version-Release number of selected component (if applicable):
libguestfs in RHEL 7
enable nbd block driver [component = qemu-kvm]
There is no general bug or documentation I can find about
what qemu will eventually support. But that information can
be found in the spec file.
My current understanding is this:
qemu | libvirt
upst.| RHEL7 | upst.| RHEL7
file Y Y Y Y
ftp Y N N N
ftps Y N N N
gluster Y Y
http Y N N N
https Y N N N
iscsi Y 
nbd Y bug 875871 Y
rbd Y Y
sheepdog Y Y
ssh Y 
tftp Y N N N
 = Supposed to be supported, but I couldn't get it to work.
 = Patch posted upstream, but needs further work.
Dan can you help to fill in the table (comment 0)?
I don't believe we've made any decisions about the block device support list for RHEL-7 yet in libvirt or kvm.
ssh support seems unlikely before at least RHEL 7.1. The reasons
are this needs further work in qemu & libvirt:
qemu: Support for more authentication types.
libvirt: Fix the ssh driver and get it upstream and test it
libguestfs: Some (minor) changes may be needed to make the
libvirt backend fully functional with ssh.
This RHEL-7-only commit was added:
Verified with libguestfs-1.22.6-16.el7.x86_64
1. test nbd driver
qemu-nbd -v -t RHEL-Server-6.4-64-hvm.raw &
virt-inspector -a nbd://10.66.84.13
2. test file driver
virt-inspector -a file:///path/RHEL-Server-6.4-64-hvm.raw
All works well, so change the status to verified
This request was resolved in Red Hat Enterprise Linux 7.0.
Contact your manager or support representative in case you have further questions about the request.