- Users - libvirt List Archives

[libvirt-users] passthrough shared dir with kvm: need to run as root?
by Raphael Bauduin 03 Oct '13

03 Oct '13

Hi, I need to mount a directory from the host in a guest, with passthough (ie, owner id and group set in the guest should be preserved and written on the host). I've read that for this to work, qemu needs to be run as root. Is there a way to start qemu as root via libvirt? Thanks raph

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[libvirt-users] Snapshots: Where they are stored and how to use them?
by Roland Giesler 02 Oct '13

02 Oct '13

Firstly I'd like to learn where a snapshot is stored once it has been made. I understand that the principle is that when changes occur in the VM, the difference is written to the snapshot, thus recording the differences between the date/time of the snapshot and the current value of the VM. Is that a correct assessment of the process? If that is indeed so, can I take regular snapshots and back then up onto external storage to provide a sort of system restore point at certain times in the past? I have scanned the server hard disks for the snapshot images after running "sudo virsh snapshot-create Windows /etc/libvirt/snapshot.xml" and the system reports a snapshot was taken, yet I cannot find any file that contains the snapshot. $ sudo virsh snapshot-list Windows Name Creation Time State ------------------------------------------------------------ Windows 2013-10-02 12:41:06 +0200 running What will happen to the snapshot if the host server is restarted? Some insight would be greatly appreciated. regards Roland

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[libvirt-users] Bridging Wireless Cards for KVM
by Joshua McKee 02 Oct '13

02 Oct '13

Hi, I hope this is the right place to ask this question. I was wondering if there is a way to set up a KVM VM using an XML document as input into Virsh that uses bridged networking over a wireless card. I understand that wireless cards to not natively support, but I was able to find a working solution here: http://blog.ericwhite.ca/articles/2011/04/creating-a-wireless-bridge/. The issue is, I can use this bridge by calling KVM directly. However, I cannot figure out how to get this same configuration on an XML file that I input into Virsh for the creation of a VM. My understanding is that libvirt calls KVM/QEMU at some point, but I may be mistaken. Thanks, Joshua

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[libvirt-users] Accessing the host server's file system from a guest OS
by Roland Giesler 02 Oct '13

02 Oct '13

Is there no way in which one can access the host's filesystem from within a guest OS. Libvirt's virt-manager GUI seems to indicate that there is, by virtue of the FileSystem Passthrough option as shown below [image: Inline image 1] The scenario I typically have is a Linux Server on a ext4 file system, with a Windows 7 Guest OS running a KVM machine. No matter what combination of options I choose, I can never "mount" the host drive in Windows to be able to transfer files from one to the other. Both VMWare Player and Virtualbox have this capability, yet I find this sorely lacking in libvirt/virt-manager. What do I need to do to make this work? regards Roland

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[libvirt-users] libvirt installtion.
by cooldharma06 01 Oct '13

01 Oct '13

hi, i am facing some error i am not able to find how to solve this. i just explain my whole things. i installed libvirt 1.1.2 from source under /opt/ folder. ./configure --with-xen=yes, make , make install. i faced some internal error so runned make clean , make distclean under libvirt source folder. then agian i tried to install libvirt 1.1.2 ./configure --prefix=/usr --localstatedir=/var --sysconfdir=/etc --with-xen=yes --with-libxl=yes make make install. i faced some error. i mailed those error in my previous mail. then i cleared (removed by make clean) the libvirt 1.1.2 and i tried to install the libvirt 1.1.1 with the following commands: ./configure --prefix=/usr --localstatedir=/var --sysconfdir=/etc --with-xen=yes make make install i am getting the below error. root(a)boss[libvirt-1.1.1]#libvirtd -v libvirtd: /usr/local/lib/libvirt.so.0: version `LIBVIRT_PRIVATE_1.1.1' not found (required by libvirtd) give me some solution to solve the above error.. regards, cooldharma06.

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[libvirt-users] LXC, libvrt-1.1.2-r3 (Gentoo), "/dev/tty12", mount /dev with inverse of 'nodev'?
by Dennis Jenkins 01 Oct '13

01 Oct '13

Hello again, TL;DR: Today I noticed that my LXC container was out of space in "/dev". It took me a few minutes to figure out why. There were only 23 files there. The "/dev" fs quota was 64K, and all was taken up. The problem was that "syslog-ng" was writing "console" messages to "/dev/tty12". But "/dev/tty12" was not a device node, so the kernel "(2)open"ed it as a file and dutifully wrote to it. I have corrected my syslog-ng config, but I was wondering.... Is there any legitimate reason to EVER have a regular file in "/dev"? If not, can libvirt or Linux be modified so that the filesystem can be mounted in such a way to prevent a regular file from ever being created there? Kind of like an inverse of the "nodev" mount option seen in various filesystems (ext3, nfs). IMHO, I would rather have syslog-ng (or other tool) fail to open a regular file in "/dev", than for it is succeed and then fill up the small fs. Thoughts? Boring stuff: Sep 30 14:06:47 localhost syslog-ng[440]: Error suspend timeout has elapsed, attempting to write again; fd='16' Sep 30 14:06:47 localhost syslog-ng[440]: I/O error occurred while writing; fd='16', error='No space left on device (28)' Sep 30 14:06:47 localhost syslog-ng[440]: Suspending write operation because of an I/O error; fd='16', time_reopen='60' This is what I see inside the container: djenkins@dwj-hfax-dev ~/src/HylaFAX+ $ find /dev | wc -l 23 dwj-hfax-dev ~ # ls -l /dev/tty* crw-rw-rw- 1 root root 5, 0 Sep 30 13:44 /dev/tty lrwxrwxrwx 1 root root 10 Sep 30 13:03 /dev/tty1 -> /dev/pts/0 -rw------- 1 root root 65536 Sep 30 14:12 /dev/tty12 ### AHHH!!! There is the problem. "syslog-ng" is writing to "/dev/tty12", but it is a file and not a real device. djenkins@dwj-hfax-dev ~/src/HylaFAX+ $ du -sh /dev 64K /dev djenkins@dwj-hfax-dev ~/src/HylaFAX+ $ df -h /dev Filesystem Size Used Avail Use% Mounted on devfs 64K 64K 0 100% /dev

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[libvirt-users] Unable to start libvirt_lxc domain a second time after shutdown
by Florian Klink 30 Sep '13

30 Sep '13

Hi, I'm unable to start a lxc domain again after shutting it down. Something doesn't seem to "clean up" the socket file (and probably more), as the error message says "Unable to start Domain: Failed to connect socket to '/var/run/libvirt/lxc/test.sock': Connection refused." I can create a domain with the same config as the one thats shutted down, but with other uid and name, of course, and I'm able to boot up this domain. However, the init process is much shorter (some filesystems are not mounted), so maybe there is still something left "open" after the lxc container is shut down? I saw the problem in libvirt 1.1.2 and current git (1.1.3-rc2 plus 7 commits, on 51e21ba7b6f59d6ad9339b2da2b75cc7704f9ecf) Configuration is something like this: <domain type='lxc'> <name>test</name> <memory unit='KiB'>1048576</memory> <currentMemory unit='KiB'>1048576</currentMemory> <vcpu placement='static'>1</vcpu> <resource> <partition>/machine</partition> </resource> <os> <type arch='x86_64'>exe</type> <init>/sbin/init</init> </os> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>restart</on_crash> <devices> <emulator>/usr/lib/libvirt/libvirt_lxc</emulator> <filesystem type='mount' accessmode='passthrough'> <source dir='/var/lib/libvirt/filesystems/test/root'/> <target dir='/'/> </filesystem> <interface type='network'> </interface> <console type='pty'> <target type='lxc' port='0'/> </console> </devices> <seclabel type='none'/> </domain> Florian

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[libvirt-users] Does libvirt support xapi/xe toolstack?
by Guillaume Thouvenin 30 Sep '13

30 Sep '13

Hello, I installed the last version of Xen (xenserver-core-0.9.0-9.x86_64 from yum) and I'm trying to manage my VMs with virsh. The version that I installed is using the Xapi/xe toolstack. The problem I have is that I'm not seeing the VM that is started with "virsh -c xen:/// list --all". Here is what I have: root# xe vm-list uuid ( RO) : 022226ed-07be-37fc-5b52-f798320e2726 name-label ( RW): vm1 power-state ( RO): running uuid ( RO) : 394fa633-f600-45f9-bea7-3bf4a9fd06fd name-label ( RW): Control domain on host: unknown power-state ( RO): running root# virsh -c xen:/// list --all Id Name State ---------------------------------------------------- # According to [1] it seems that libvirt is using Xend daemon to communicate. The problem is that Xend is now deprecated since Xen 4.1. So am I wrong with this assumption or is there something to configure to be able to use libvirt with Xapi/XE toolstack? I looked in the documentation but I only found [2] but I didn't see any special settings... Regards, Guillaume [1] http://libvirt.org/architecture.html [2] http://libvirt.org/drvxen.html

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[libvirt-users] virt-manager could not start with error "version `LIBVIRT_PRIVATE_0.10.2' not found "
by jimmy he 30 Sep '13

30 Sep '13

Hello all, i am now running xen 4.2.3 on centos 6.4. As we know, the default libvirt package could not work well with xen on centos6.x. So, i compile the libvirt by my self, and i have compiled libvirt-1.1.1, libvirt-1.1.2, libvirt-1.1.3. After the installation of libvirt, i run virt-manager, but it print error as below. *ImportError: /usr/local/lib/libvirt.so.0: version `LIBVIRT_PRIVATE_0.10.2' not found (required by /usr/lib/python2.6/site-packages/libvirtmod.so)* I found one topic talk about the erorr, but get nothing https://www.centos.org/modules/newbb/viewtopic.php?topic_id=41893&forum=56 anyone meet the same error as me? any response is appreciated!

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[libvirt-users] virNodeInfo returns MBytes instead of bytes
by Sam Giraffe 30 Sep '13

30 Sep '13

Hi, http://www.libvirt.org/html/libvirt-libvirt.html#virNodeInfo says that memory size is in kilobytes, however when I use this call I get an answer in Megabytes, see below. The hypervisor has 16 GB of RAM. $ python Python 2.6.6 (r266:84292, Jul 10 2013, 22:48:45) [GCC 4.4.7 20120313 (Red Hat 4.4.7-3)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import libvirt >>> conn=libvirt.open("qemu+ssh://xx@xx.xxx.com/system") Enter passphrase for key '/home/xx/.ssh/id_rsa': >>> hv_info=conn.getInfo() >>> hv_info ['x86_64', 15919, 8, 3292, 1, 1, 4, 2] 15,919 is the number I am referencing, should that not be in bytes and not MB? 8 is the number of cores, CPU is 3.2Ghz. $ rpm -q libvirt libvirt-0.10.2-18.el6_4.14.x86_64 $ uname -a Linux xx.xxx.com 2.6.32-358.18.1.el6.x86_64 #1 SMP Wed Aug 28 17:19:38 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux Thanks

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