xen hvm live migration fails due to packaging error

[Greg Harris]

Binary package hint: xen-utils-3.2

This is under Hardy 8.10:

Migration of Xen HVM domains fails due to the following code under /usr/lib/python2.5/site-packages/xen/XendCheckpoint.py:

 if os.path.exists("/var/lib/xen/qemu-save.%d" % dominfo.getDomid()):
            write_exact(fd, QEMU_SIGNATURE, "could not write qemu signature")
            qemu_fd = os.open("/var/lib/xen/qemu-save.%d" % dominfo.getDomid(),

Ubuntu has moved the location the qemu-save state is stored to under /var/lib/xend/qemu-save.%d. This means the qemu-dm state is not transmitted during migration and the domain fails to start at its destination because it has no information about the qemu device-mapper state...

A workaround is to symlink /var/lib/xen -> /var/lib/xend on the senders side after which Xen migration starts working again. There are several other references to this non-existant path that may be breaking other things in XendCheckpoint.py and image.py.