Verified. on fresh xenial guest in openstack. See below.
$ lsb_release -sc xenial $ cat /etc/cloud/build.info build_name: server serial: 20180126
$ wget "$url" --progress=dot:giga -O xenial-server-cloudimg-amd64-disk1.img
$ dpkg -S `which mount-image-callback` cloud-image-utils: /usr/bin/mount-image-callback
$ dpkg-query --show cloud-image-utils cloud-image-utils 0.27-0ubuntu25
$ sha256sum < xenial-server-cloudimg-amd64-disk1.img da7a59cbaf43eaaa83ded0b0588bdcee4e722d9355bd6b9bfddd01b2e7e372e2 -
$ cp -a xenial-server-cloudimg-amd64-disk1.img disk.img
$ sudo mount-image-callback -v disk.img -- true waiting on pidfile for /dev/nbd0 in /sys/block/nbd0/pid connected disk.img (qcow2) to /dev/nbd0. waiting for device. partitioned disk. mounted /dev/nbd0p1 via qemu-nbd /dev/nbd0 invoking: MOUNTPOINT=/tmp/mount-image-callback.XRd6Rk/mp true cmd returned 0. unmounting /tmp/mount-image-callback.XRd6Rk/mp
$ sudo mount-image-callback --read-only disk.img -- \ sh -c 'cd $MOUNTPOINT && cat etc/cloud/build.info' mount: /dev/nbd0p1 is write-protected, mounting read-only build_name: server serial: 20180126
Verified. on fresh xenial guest in openstack. See below.
$ lsb_release -sc build.info
xenial
$ cat /etc/cloud/
build_name: server
serial: 20180126
$ wget "$url" --progress=dot:giga -O xenial- server- cloudimg- amd64-disk1. img
$ dpkg -S `which mount-image- callback` mount-image- callback
cloud-image-utils: /usr/bin/
$ dpkg-query --show cloud-image-utils
cloud-image-utils 0.27-0ubuntu25
$ sha256sum < xenial- server- cloudimg- amd64-disk1. img a83ded0b0588bdc ee4e722d9355bd6 b9bfddd01b2e7e3 72e2 -
da7a59cbaf43eaa
$ cp -a xenial- server- cloudimg- amd64-disk1. img disk.img
$ sudo mount-image- callback -v disk.img -- true /tmp/mount- image-callback. XRd6Rk/ mp true image-callback. XRd6Rk/ mp
waiting on pidfile for /dev/nbd0 in /sys/block/nbd0/pid
connected disk.img (qcow2) to /dev/nbd0. waiting for device.
partitioned disk.
mounted /dev/nbd0p1 via qemu-nbd /dev/nbd0
invoking: MOUNTPOINT=
cmd returned 0. unmounting /tmp/mount-
$ sudo mount-image- callback --read-only disk.img -- \ build.info'
sh -c 'cd $MOUNTPOINT && cat etc/cloud/
mount: /dev/nbd0p1 is write-protected, mounting read-only
build_name: server
serial: 20180126