October 2012 - Libguestfs - libguestfs List Archives

[PATCH for discussion only] launch: Add add_drive 'serial' option.
by Richard W.M. Jones 04 Oct '12

04 Oct '12

These two patches are for discussion of the proposed API only (in fact, it doesn't compile). virtio-scsi allows you to name drives (using the qemu serial=... option or libvirt <serial/>). Let's allow users to specify a serial when adding a drive, and then map that to a well-known name in the libguestfs API (/dev/disk/guests/SERIAL[PARTNUM]). Note that I chose not to change list-devices / list-partitions. These still return raw device names (which still exist, even if the serial is used). Instead there is a new API called list-serial-names which returns a mapping of the serial names to raw device names. This patch is in preparation for hotplugging. The plan would be to remove the restriction that add_drive{_opts} has to be called before launch. If it's called after launch (ie. hotplugging) then we strongly recommend that users specify the serial option so the disk has a predictable name. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones virt-df lists disk usage of guests without needing to install any software inside the virtual machine. Supports Linux and Windows. http://et.redhat.com/~rjones/virt-df/

1 0

Passphrases for libguestfs disks
by Richard W.M. Jones 03 Oct '12

03 Oct '12

Dan: Couple of points I forgot to raise at the meeting: (1) Libguestfs identifies keys differently from strings in the generator (Key vs String), but DOESN'T mlock keys into memory. This is (or *was* -- see below) for a good reason: Because we pass these keys into the appliance, and because the appliance runs in regular qemu, there's not much point in going to the trouble in libguestfs when qemu is just going to spill them to swap anyway. (2) Libguestfs has historically never supported host-encrypted devices, eg. encrypted qcow2 files. Mainly because no one has ever asked for it. With the libvirt backend we ought to be able to support these. We could create a transient secret, in which case we would modify libguestfs to do the necessary mlocking. Or (perhaps better) we might pass the UUID of the secret to libvirt, and let libvirt manage the secret entirely. I'm not sure this latter method will work given that essentially most of the time we are using the session libvirtd. Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones virt-top is 'top' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://et.redhat.com/~rjones/virt-top

1 0

no man page for guestfsd
by Olaf Hering 03 Oct '12

03 Oct '12

rpmlint complains that guestfsd has no man page. I think its a good idea to provide one also for guestfsd. Olaf

2 2