Richard W.M. Jones
2021-Jan-11 15:30 UTC
[Libguestfs] Can I use virt-filesystem on a running VM?
On Mon, Jan 11, 2021 at 12:04:22PM -0300, Sergio Belkin wrote:> > > El lun, 11 ene 2021 a las 6:41, Richard W.M. Jones (<rjones at redhat.com>) > escribi?: > > On Sat, Jan 09, 2021 at 05:23:13PM -0300, Sergio Belkin wrote: > > So do you think that is a SELinux issue (I haven't found anything > > related to this with ausearch or audit logs)? So, can > > virt-filesystems crash the guest? (I had to reboot and repair the > > xfs) > > It's not that virt-filesystems is affecting the guest, it's that > libvirtd relabels the disks and as a result original qemu loses access > to its disks. > > Try with LIBGUESTFS_BACKEND=direct which doesn't use libvirt or > SELinux labelling. > > Rich. > > -- > Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/ > ~rjones > Read my programming and virtualization blog: http://rwmj.wordpress.com > libguestfs lets you edit virtual machines.? Supports shell scripting, > bindings from many languages.? http://libguestfs.org > > > > Hi Richard, thanks for your kind explanation and help. It worked like a charm. > > In case it becomes useful to someone, I get: > > Name ? ? ? ? ? ? ? ? ? ?Type ? ? ? VFS ?Label MBR Size Parent ? ? ? ? ? ? UUID > /dev/sda1 ? ? ? ? ? ? ? filesystem xfs ?- ? ? - ? 500M - ? ? ? ? ? ? ? ? > ?8746b377-7e21-4cb5-b269-c034720d65c1 > /dev/centos_lx0001/root filesystem xfs ?- ? ? - ? 48G ?- ? ? ? ? ? ? ? ? > ?3a3d6041-5f1c-479f-92cf-42a569d57bab > /dev/centos_lx0001/swap filesystem swap - ? ? - ? 2,0G - ? ? ? ? ? ? ? ? > ?76addd8c-7aa1-4779-8a86-70ab6baca2b2 > /dev/centos_lx0001/root lv ? ? ? ? - ? ?- ? ? - ? 48G ?/dev/centos_lx0001 > 2d4fOO-fXZm-HDHi-CiTY-umH3-Icu9-peXjGZ > /dev/centos_lx0001/swap lv ? ? ? ? - ? ?- ? ? - ? 2,0G /dev/centos_lx0001 > mbKcjk-YXVg-MjhS-L0IA-cNgg-KF0o-4uxvc5 > /dev/centos_lx0001 ? ? ?vg ? ? ? ? - ? ?- ? ? - ? 50G ?/dev/sda2 ? ? ? ? > ?17HB8hKfxKZHis9Tcrq2XoFLldN0fAft > /dev/sda2 ? ? ? ? ? ? ? pv ? ? ? ? - ? ?- ? ? - ? 50G ?- ? ? ? ? ? ? ? ? > ?NZT8FHFBUed0PZyKsrXLWAnemghOO0J7 > /dev/sda1 ? ? ? ? ? ? ? partition ?- ? ?- ? ? 83 ?500M /dev/sda ? ? ? ? ? - > /dev/sda2 ? ? ? ? ? ? ? partition ?- ? ?- ? ? 8e ?50G ?/dev/sda ? ? ? ? ? - > /dev/sda ? ? ? ? ? ? ? ?device ? ? - ? ?- ? ? - ? 50G ?- ? ? ? ? ? ? ? ? ?- > > Jut only a question about this output, just out of curiosity why does it print > /dev/sda* instead /dev/vda* ?We don't know what drivers are installed in the guest, or (in virt-filesystems) even what the guest is. Maybe it's Linux with virtio. Maybe it's Windows. So we use a canonical naming scheme for devices and partitions: https://libguestfs.org/guestfs.3.html#block-device-naming Rich. -- Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones Read my programming and virtualization blog: http://rwmj.wordpress.com virt-top is 'top' for virtual machines. Tiny program with many powerful monitoring features, net stats, disk stats, logging, etc. http://people.redhat.com/~rjones/virt-top
Sergio Belkin
2021-Jan-11 19:21 UTC
[Libguestfs] Can I use virt-filesystem on a running VM?
El lun, 11 ene 2021 a las 12:30, Richard W.M. Jones (<rjones at redhat.com>) escribi?:> On Mon, Jan 11, 2021 at 12:04:22PM -0300, Sergio Belkin wrote: > > > > > > El lun, 11 ene 2021 a las 6:41, Richard W.M. Jones (<rjones at redhat.com>) > > escribi?: > > > > On Sat, Jan 09, 2021 at 05:23:13PM -0300, Sergio Belkin wrote: > > > So do you think that is a SELinux issue (I haven't found anything > > > related to this with ausearch or audit logs)? So, can > > > virt-filesystems crash the guest? (I had to reboot and repair the > > > xfs) > > > > It's not that virt-filesystems is affecting the guest, it's that > > libvirtd relabels the disks and as a result original qemu loses > access > > to its disks. > > > > Try with LIBGUESTFS_BACKEND=direct which doesn't use libvirt or > > SELinux labelling. > > > > Rich. > > > > -- > > Richard Jones, Virtualization Group, Red Hat > http://people.redhat.com/ > > ~rjones > > Read my programming and virtualization blog: > http://rwmj.wordpress.com > > libguestfs lets you edit virtual machines. Supports shell scripting, > > bindings from many languages. http://libguestfs.org > > > > > > > > Hi Richard, thanks for your kind explanation and help. It worked like a > charm. > > > > In case it becomes useful to someone, I get: > > > > Name Type VFS Label MBR Size Parent > UUID > > /dev/sda1 filesystem xfs - - 500M - > > 8746b377-7e21-4cb5-b269-c034720d65c1 > > /dev/centos_lx0001/root filesystem xfs - - 48G - > > 3a3d6041-5f1c-479f-92cf-42a569d57bab > > /dev/centos_lx0001/swap filesystem swap - - 2,0G - > > 76addd8c-7aa1-4779-8a86-70ab6baca2b2 > > /dev/centos_lx0001/root lv - - - 48G /dev/centos_lx0001 > > 2d4fOO-fXZm-HDHi-CiTY-umH3-Icu9-peXjGZ > > /dev/centos_lx0001/swap lv - - - 2,0G /dev/centos_lx0001 > > mbKcjk-YXVg-MjhS-L0IA-cNgg-KF0o-4uxvc5 > > /dev/centos_lx0001 vg - - - 50G /dev/sda2 > > 17HB8hKfxKZHis9Tcrq2XoFLldN0fAft > > /dev/sda2 pv - - - 50G - > > NZT8FHFBUed0PZyKsrXLWAnemghOO0J7 > > /dev/sda1 partition - - 83 500M /dev/sda > - > > /dev/sda2 partition - - 8e 50G /dev/sda > - > > /dev/sda device - - - 50G - > - > > > > Jut only a question about this output, just out of curiosity why does it > print > > /dev/sda* instead /dev/vda* ? > > We don't know what drivers are installed in the guest, or (in > virt-filesystems) even what the guest is. Maybe it's Linux with > virtio. Maybe it's Windows. So we use a canonical naming scheme for > devices and partitions: > > https://libguestfs.org/guestfs.3.html#block-device-naming > > Rich. > > -- > Richard Jones, Virtualization Group, Red Hat > http://people.redhat.com/~rjones > Read my programming and virtualization blog: http://rwmj.wordpress.com > virt-top is 'top' for virtual machines. Tiny program with many > powerful monitoring features, net stats, disk stats, logging, etc. > http://people.redhat.com/~rjones/virt-top > >Thanks again! -- -- Sergio Belkin LPIC-2 Certified - http://www.lpi.org -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://listman.redhat.com/archives/libguestfs/attachments/20210111/b4b8729b/attachment.htm>