Public bug reported: we run following version of qemu-img: $ qemu-img --version qemu-img version 2.5.0 (Debian 1:2.5+dfsg-5ubuntu10.41), Copyright (c) 2004-2008 Fabrice Bellard $
Here is os version: $ cat /etc/os-release NAME="Ubuntu" VERSION="16.04.6 LTS (Xenial Xerus)" ID=ubuntu ID_LIKE=debian PRETTY_NAME="Ubuntu 16.04.6 LTS" VERSION_ID="16.04" HOME_URL="http://www.ubuntu.com/" SUPPORT_URL="http://help.ubuntu.com/" BUG_REPORT_URL="http://bugs.launchpad.net/ubuntu/" VERSION_CODENAME=xenial UBUNTU_CODENAME=xenial $ When we use qemu-img for conversion of qcow2 to vhd newly created file doesnt show batmap summary when we run: # vhd-util read -p -n centos76.vhd VHD Footer Summary: ------------------- Cookie : conectix Features : (0x00000002) <RESV> File format version : Major: 1, Minor: 0 Data offset : 512 Timestamp : Mon Mar 4 13:21:27 2019 Creator Application : 'qemu' Creator version : Major: 5, Minor: 3 Creator OS : Windows Original disk size : 8192 MB (8590417920 Bytes) Current disk size : 8192 MB (8590417920 Bytes) Geometry : Cyl: 16645, Hds: 16, Sctrs: 63 : = 8192 MB (8590417920 Bytes) Disk type : Dynamic hard disk Checksum : 0xfffff119|0xfffff119 (Good!) UUID : 23772822-a66c-45a2-be37-8474604147c7 Saved state : No Hidden : 0 VHD Header Summary: ------------------- Cookie : cxsparse Data offset (unusd) : 18446744073709 Table offset : 1536 Header version : 0x00010000 Max BAT size : 4097 Block size : 2097152 (2 MB) Parent name : Parent UUID : 00000000-0000-0000-0000-000000000000 Parent timestamp : Fri Dec 31 19:00:00 1999 Checksum : 0xfffff466|0xfffff466 (Good!) # I am not so strong in VHD format details and not exactly sure how batmap is needed, but when I do conversion of qcow2 image by using vhd-util at the end I get file with proper batmap summary. In our environment we use CloudStack and Citrix and we use those converted from qcow2 to vhd images as templates. In general there is no problems, but whenever we create snapshot out of VM created from such template vhd-util read command starts giving us error like below: # ------------------- Cookie : conectix Features : (0x00000002) <RESV> File format version : Major: 1, Minor: 0 Data offset : 512 Timestamp : Thu Aug 29 16:04:30 2019 Creator Application : 'tap' Creator version : Major: 1, Minor: 3 Creator OS : Unknown! Original disk size : 8194 MB (8592031744 Bytes) Current disk size : 8194 MB (8592031744 Bytes) Geometry : Cyl: 16648, Hds: 16, Sctrs: 63 : = 8193 MB (8591966208 Bytes) Disk type : Dynamic hard disk Checksum : 0xfffff074|0xfffff074 (Good!) UUID : 2b3cac7d-16e1-4771-b8cd-bb8c7876c761 Saved state : No Hidden : 0 VHD Header Summary: ------------------- Cookie : cxsparse Data offset (unusd) : 18446744073709 Table offset : 1536 Header version : 0x00010000 Max BAT size : 4097 Block size : 2097152 (2 MB) Parent name : Parent UUID : 00000000-0000-0000-0000-000000000000 Parent timestamp : Sat Jan 1 00:00:00 2000 Checksum : 0xfffff466|0xfffff466 (Good!) failed to get batmap header # With the templates that show correct batmap summary that are created by conversion of qcow2 image by vhd-util convert we don't have such problems. So I wanted to check with community if not existence of the batmap can cause (be the reason of) this behaviour later on snapshot creation stage? Should we always have batmap summary on output of vhd-util read command? ** Affects: qemu Importance: Undecided Status: New ** Tags: qemu-img -- You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1842925 Title: no batmap on convertion from qcow2 to vhd Status in QEMU: New Bug description: we run following version of qemu-img: $ qemu-img --version qemu-img version 2.5.0 (Debian 1:2.5+dfsg-5ubuntu10.41), Copyright (c) 2004-2008 Fabrice Bellard $ Here is os version: $ cat /etc/os-release NAME="Ubuntu" VERSION="16.04.6 LTS (Xenial Xerus)" ID=ubuntu ID_LIKE=debian PRETTY_NAME="Ubuntu 16.04.6 LTS" VERSION_ID="16.04" HOME_URL="http://www.ubuntu.com/" SUPPORT_URL="http://help.ubuntu.com/" BUG_REPORT_URL="http://bugs.launchpad.net/ubuntu/" VERSION_CODENAME=xenial UBUNTU_CODENAME=xenial $ When we use qemu-img for conversion of qcow2 to vhd newly created file doesnt show batmap summary when we run: # vhd-util read -p -n centos76.vhd VHD Footer Summary: ------------------- Cookie : conectix Features : (0x00000002) <RESV> File format version : Major: 1, Minor: 0 Data offset : 512 Timestamp : Mon Mar 4 13:21:27 2019 Creator Application : 'qemu' Creator version : Major: 5, Minor: 3 Creator OS : Windows Original disk size : 8192 MB (8590417920 Bytes) Current disk size : 8192 MB (8590417920 Bytes) Geometry : Cyl: 16645, Hds: 16, Sctrs: 63 : = 8192 MB (8590417920 Bytes) Disk type : Dynamic hard disk Checksum : 0xfffff119|0xfffff119 (Good!) UUID : 23772822-a66c-45a2-be37-8474604147c7 Saved state : No Hidden : 0 VHD Header Summary: ------------------- Cookie : cxsparse Data offset (unusd) : 18446744073709 Table offset : 1536 Header version : 0x00010000 Max BAT size : 4097 Block size : 2097152 (2 MB) Parent name : Parent UUID : 00000000-0000-0000-0000-000000000000 Parent timestamp : Fri Dec 31 19:00:00 1999 Checksum : 0xfffff466|0xfffff466 (Good!) # I am not so strong in VHD format details and not exactly sure how batmap is needed, but when I do conversion of qcow2 image by using vhd-util at the end I get file with proper batmap summary. In our environment we use CloudStack and Citrix and we use those converted from qcow2 to vhd images as templates. In general there is no problems, but whenever we create snapshot out of VM created from such template vhd-util read command starts giving us error like below: # ------------------- Cookie : conectix Features : (0x00000002) <RESV> File format version : Major: 1, Minor: 0 Data offset : 512 Timestamp : Thu Aug 29 16:04:30 2019 Creator Application : 'tap' Creator version : Major: 1, Minor: 3 Creator OS : Unknown! Original disk size : 8194 MB (8592031744 Bytes) Current disk size : 8194 MB (8592031744 Bytes) Geometry : Cyl: 16648, Hds: 16, Sctrs: 63 : = 8193 MB (8591966208 Bytes) Disk type : Dynamic hard disk Checksum : 0xfffff074|0xfffff074 (Good!) UUID : 2b3cac7d-16e1-4771-b8cd-bb8c7876c761 Saved state : No Hidden : 0 VHD Header Summary: ------------------- Cookie : cxsparse Data offset (unusd) : 18446744073709 Table offset : 1536 Header version : 0x00010000 Max BAT size : 4097 Block size : 2097152 (2 MB) Parent name : Parent UUID : 00000000-0000-0000-0000-000000000000 Parent timestamp : Sat Jan 1 00:00:00 2000 Checksum : 0xfffff466|0xfffff466 (Good!) failed to get batmap header # With the templates that show correct batmap summary that are created by conversion of qcow2 image by vhd-util convert we don't have such problems. So I wanted to check with community if not existence of the batmap can cause (be the reason of) this behaviour later on snapshot creation stage? Should we always have batmap summary on output of vhd-util read command? To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1842925/+subscriptions