Hi All,

I am unable to figure out the issue here, when I try to create a filesystem (ext4) on a virtual disk using qemu-nbd. This happens intermittently.

Following is the sequence of commands:-

$> qemu-img create -f qcow2 test.qcow2 30G

$> qemu-nbd --connect=/dev/nbd0 test.qcow2

$> mkfs.ext4 /dev/nbd0

 mkfs.ext4: Device size reported to be zero.  Invalid partition specified, or

Thu Jun 13 14:44:24 2019 partition table wasn't reread after running fdisk, due to

Thu Jun 13 14:44:24 2019 a modified partition being busy and in use.  You may need to reboot

Thu Jun 13 14:44:24 2019 to re-read your partition table.

Following is the version details:

root@localhost:~# qemu-img --version

qemu-img version 2.8.1(Debian 1:2.8+dfsg-6+deb9u7)

root@localhost:~# qemu-nbd --version

qemu-nbd version 0.0.1

Written by Anthony Liguori.

This is free software; see the source for copying conditions. There is NO

warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

root@localhost:~# uname -a

Linux localhost 4.9.0-9-amd64 #1 SMP Debian 4.9.168-1+deb9u2 (2019-05-13) x86_64 GNU/Linux

Regards
Tanmoy Sinha