[libvirt] [ANNOUNCE] virt-df 2.1.0 - a 'df' tool for virtual guests
I'm pleased to announce the most recent release of virt-df (2.1.0). Virt-df is 'df' for virtual guests. Run the program on the host / dom0 to display disk space used and available on all partitions on all guests. You don't need to run any sort of program/agent within the guest. Home page: http://et.redhat.com/~rjones/virt-df/ Source/binaries: http://et.redhat.com/~rjones/virt-df/files/ Developer repository: http://hg.et.redhat.com/virt/applications/virt-df--devel This version supports most common filesystems and partitioning schemes, including: - Linux ext2/3 - DOS FAT32 - Windows NTFS - Linux LVM2 (volume groups and logical volumes) - Primary and extended disk partitions - Linux swap - Linux suspend partition You can run it in your host / dom0 to display guest filesystems: # virt-df -c qemu:///system -h Filesystem Size Used Available Type rhel51x32kvm:hda1 96.8 MiB 14.6 MiB 82.2 MiB Linux ext2/3 rhel51x32kvm:VolGroup00/LogVol00 6.4 GiB 3.6 GiB 2.8 GiB Linux ext2/3 rhel51x32kvm:VolGroup00/LogVol01 992.0 MiB Linux swap You can also run it on general disk images, or disk devices: # virt-df -t /dev/sda Filesystem 1K-blocks Used Available Type /dev/sda:hda1 25599996 11309448 14290552 Windows NTFS /dev/sda:hda2 992016 93772 898244 Linux ext2/3 /dev/sda:F9VG/F9Root 23316072 7818164 15497908 Linux ext2/3 /dev/sda:F9VG/F9Swap 1015808 Linux swap /dev/sda:RHEL51VG/RHEL51Root 22382184 7796640 14585544 Linux ext2/3 /dev/sda:RHEL51VG/RHEL51Swap 2031616 Linux swap /dev/sda:VolGroup/FAT32Test 916736 4 914676 DOS/Windows You can write the output to a CSV file (use --csv option) in order to import the data easily into spreadsheets and databases. Included also is an experimental command line tool called 'diskzip' which intelligently compresses disk images by leaving out the bits which aren't actually used in the filesystems / partitions / volume groups contained within. Rich. -- Richard Jones, Emerging Technologies, Red Hat http://et.redhat.com/~rjones virt-p2v converts physical machines to virtual machines. Boot with a live CD or over the network (PXE) and turn machines into Xen guests. http://et.redhat.com/~rjones/virt-p2v
On Tue, May 13, 2008 at 05:42:38PM +0100, Richard W.M. Jones wrote:
I'm pleased to announce the most recent release of virt-df (2.1.0).
Virt-df is 'df' for virtual guests. Run the program on the host / dom0 to display disk space used and available on all partitions on all guests. You don't need to run any sort of program/agent within the guest.
Home page: http://et.redhat.com/~rjones/virt-df/ Source/binaries: http://et.redhat.com/~rjones/virt-df/files/ Developer repository: http://hg.et.redhat.com/virt/applications/virt-df--devel
This version supports most common filesystems and partitioning schemes, including: - Linux ext2/3 - DOS FAT32 - Windows NTFS - Linux LVM2 (volume groups and logical volumes) - Primary and extended disk partitions - Linux swap - Linux suspend partition
I'm assuming this only works for raw file & block devices ? Are you planning to support the funky QCow / VMDK formats too ? The other thing that could be annoying is that Fedora 9 support for encrypting all volumes - might need to prompt for a decryption key for that.
Included also is an experimental command line tool called 'diskzip' which intelligently compresses disk images by leaving out the bits which aren't actually used in the filesystems / partitions / volume groups contained within.
That's pretty neat. Which file systems does that work for ? VMWare have a funky guest tool which tries to let you get to a similar point. It works by basically openning a file inside the guest VM and filling it with zeros until the entire disk is full. THeir backend can then detect and discard all the sectors with zeros. Understanding the filesystem metdata is a much nicer way todo this :-) Regards, Daniel -- |: Red Hat, Engineering, Boston -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|
On Thu, May 15, 2008 at 02:54:53PM +0100, Daniel P. Berrange wrote:
This version supports most common filesystems and partitioning schemes, including: - Linux ext2/3 - DOS FAT32 - Windows NTFS - Linux LVM2 (volume groups and logical volumes) - Primary and extended disk partitions - Linux swap - Linux suspend partition
I'm assuming this only works for raw file & block devices ? Are you planning to support the funky QCow / VMDK formats too ?
Yes, interesting point. Since I always use flat files or straight partitions for my guests I admit I hadn't given this much thought :-) However support for these formats is just a matter of decoding enough of the structure to enable the same mappings to be made in the 'virt-df' library, same as for LVM2 or indeed MBR partitions now. I'll take a look at it. IIRC there are several different undocumented variations on the QCow format?
The other thing that could be annoying is that Fedora 9 support for encrypting all volumes - might need to prompt for a decryption key for that.
Yes -- any encrypted volumes aren't going to work at the moment, and couldn't work unless there was a way to access the passphrase.
Included also is an experimental command line tool called 'diskzip' which intelligently compresses disk images by leaving out the bits which aren't actually used in the filesystems / partitions / volume groups contained within.
That's pretty neat. Which file systems does that work for ? VMWare have a funky guest tool which tries to let you get to a similar point. It works by basically openning a file inside the guest VM and filling it with zeros until the entire disk is full. THeir backend can then detect and discard all the sectors with zeros. Understanding the filesystem metdata is a much nicer way todo this :-)
It works with most of the formats supported by virt-df. For MBR & LVM once you've parsed the partition tables / LVM metadata, then the information you need just falls out naturally. For NTFS & DOS FAT (you won't believe it but ...) you need to find the allocation bitmaps/tables in both cases in order to calculate blocks used/free for df anyway. For ext2 it's a little bit more tricky because one needs to additionally parse the group block free bitmaps [this bit doesn't work at the moment, but is in principle very simple to add]. Rich. -- Richard Jones, Emerging Technologies, Red Hat http://et.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
On Thu, May 15, 2008 at 07:53:55PM +0100, Richard W.M. Jones wrote:
On Thu, May 15, 2008 at 02:54:53PM +0100, Daniel P. Berrange wrote:
This version supports most common filesystems and partitioning schemes, including: - Linux ext2/3 - DOS FAT32 - Windows NTFS - Linux LVM2 (volume groups and logical volumes) - Primary and extended disk partitions - Linux swap - Linux suspend partition
I'm assuming this only works for raw file & block devices ? Are you planning to support the funky QCow / VMDK formats too ?
Yes, interesting point. Since I always use flat files or straight partitions for my guests I admit I hadn't given this much thought :-) However support for these formats is just a matter of decoding enough of the structure to enable the same mappings to be made in the 'virt-df' library, same as for LVM2 or indeed MBR partitions now.
I'll take a look at it. IIRC there are several different undocumented variations on the QCow format?
There's version 1, and version 2. And then the incompatible version 2 inflicted by Xen :-(
The other thing that could be annoying is that Fedora 9 support for encrypting all volumes - might need to prompt for a decryption key for that.
Yes -- any encrypted volumes aren't going to work at the moment, and couldn't work unless there was a way to access the passphrase.
The passphrase is in the user's brain. THe OS prompts for it at boot time, so virt-df would need todo similar if it wanted to support decryption. Perhaps its just not a important use case. In the ISP model, guest admins won't trust the host admin so you won't have the keys anyway. If the guest admin does trust the host admin, would they really be using encryption in the guest ? Dan. -- |: Red Hat, Engineering, Boston -o- http://people.redhat.com/berrange/ :| |: http://libvirt.org -o- http://virt-manager.org -o- http://ovirt.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: GnuPG: 7D3B9505 -o- F3C9 553F A1DA 4AC2 5648 23C1 B3DF F742 7D3B 9505 :|
participants (2)
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Daniel P. Berrange -
Richard W.M. Jones