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diff --git a/virt-df/virt-df.txt b/virt-df/virt-df.txt deleted file mode 100644 index aa02a8f..0000000 --- a/virt-df/virt-df.txt +++ /dev/null @@ -1,144 +0,0 @@ -NAME - virt-df - 'df'-like utility for virtualization stats - -SUMMARY - virt-df [-options] - -DESCRIPTION - virt-df is a df(1)-like utility for showing the actual disk usage of - guests. Many command line options are the same as for ordinary *df*. - - It uses libvirt so it is capable of showing stats across a variety of - different virtualization systems. - - There are some shortcomings to the whole approach of reading disk state - from outside the guest. Please read SHORTCOMINGS section below for more - details. - -OPTIONS - -a, --all - Show all domains. The default is show only running (active) domains. - - -c uri, --connect uri - Connect to libvirt URI. The default is to connect to the default - libvirt URI, normally Xen. - - --debug - Emit debugging information on stderr. Please supply this if you - report a bug. - - -h, --human-readable - Display human-readable sizes (eg. 10GiB). - - -i, --inodes - Display inode information. - - --help - Display usage summary. - - -t diskimage - Test mode. Instead of checking libvirt for domain information, this - runs virt-df directly on the disk image (or device) supplied. You - may specify the -t option multiple times. - - --version - Display version and exit. - -SHORTCOMINGS - virt-df spies on the guest's disk image to try to work out how much disk - space it is actually using. There are some shortcomings to this, - described here. - - (1) It does not work over remote connections. The storage API does not - support peeking into remote disks, and libvirt has rejected a request to - add this support. - - (2) It only understands a limited set of partition types. Assuming that - the files and partitions that we get back from libvirt / Xen correspond - to block devices in the guests, we can go some way towards manually - parsing those partitions to find out what they contain. We can read the - MBR, LVM, superblocks and so on. However that's a lot of parsing work, - and currently there is no library which understands a wide range of - partition schemes and filesystem types (not even libparted which doesn't - support LVM yet). The Linux kernel does support that, but there's not - really any good way to access that work. - - The current implementation uses a hand-coded parser which understands - some simple formats (MBR, LVM2, ext2/3). In future we should use - something like libparted. - - (3) The statistics you get are delayed. The real state of, for example, - an ext2 filesystem is only stored in the memory of the guest's kernel. - The ext2 superblock contains some meta-information about blocks used and - free, but this superblock is not up to date. In fact the guest kernel - may not update it even on a 'sync', not until the filesystem is - unmounted. Some operations do appear to write the superblock, for - example fsync(2) [that is my reading of the ext2/3 source code at - least]. - -SECURITY - The current code tries hard to be secure against malicious guests, for - example guests which set up malicious disk partitions. - -SEE ALSO - df(1), virsh(1), xm(1), <http://www.libvirt.org/ocaml/>, - <http://www.libvirt.org/>, <http://et.redhat.com/~rjones/>, - <http://caml.inria.fr/> - -AUTHORS - Richard W.M. Jones <rjones @ redhat . com> - -COPYRIGHT - (C) Copyright 2007-2008 Red Hat Inc., Richard W.M. Jones - http://libvirt.org/ - - This program is free software; you can redistribute it and/or modify it - under the terms of the GNU General Public License as published by the - Free Software Foundation; either version 2 of the License, or (at your - option) any later version. - - This program is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General - Public License for more details. - - You should have received a copy of the GNU General Public License along - with this program; if not, write to the Free Software Foundation, Inc., - 675 Mass Ave, Cambridge, MA 02139, USA. - -REPORTING BUGS - Bugs can be viewed on the Red Hat Bugzilla page: - <https://bugzilla.redhat.com/>. - - If you find a bug in virt-df, please follow these steps to report it: - - 1. Check for existing bug reports - Go to <https://bugzilla.redhat.com/> and search for similar bugs. - Someone may already have reported the same bug, and they may even - have fixed it. - - 2. Capture debug and error messages - Run - - virt-df --debug > virt-df.log 2>&1 - - and keep *virt-df.log*. It contains error messages which you should - submit with your bug report. - - 3. Get version of virt-df and version of libvirt. - Run - - virt-df --version - - 4. Submit a bug report. - Go to <https://bugzilla.redhat.com/> and enter a new bug. Please - describe the problem in as much detail as possible. - - Remember to include the version numbers (step 3) and the debug - messages file (step 2). - - 5. Assign the bug to rjones @ redhat.com - Assign or reassign the bug to rjones @ redhat.com (without the - spaces). You can also send me an email with the bug number if you - want a faster response. - |