- Users - libvirt List Archives

Re: [libvirt-users] Monitoring and statistics through libvirt
by Peter Phaal 16 Oct '10

16 Oct '10

On Fri, Oct 01, 2010 at 03:47:23PM +0200, Tomi wrote: > Hi folks, > > is it possible to monitor and gather statistics in realtime (CPU, > memory, HDD, network, ... - something like dstat) of guest systems > with libvirt through console from host system (KVM based)? If yes, do > those guests need to be created through libvirt? Thanks for your help > and time. If you have a large number of servers to monitor, you might want to look at the Host sFlow agent: http://host-sflow.sourceforge.net/ The Host sFlow agent is installed on the server and locally polls physical server statistics and VM statistics using libvirt. The statistics are exported using the sFlow protocol. http://www.sflow.org/ If you want detailed network visibility then the Open vSwitch includes sFlow monitoring of inter-VM traffic: http://openvswitch.org/ For more information, see: http://blog.sflow.com/2010/10/kvm.html http://blog.sflow.com/2010/10/sflowtrend-adds-server-performance.html Peter

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[libvirt-users] NFS4 + SELinux
by Mike Hall 15 Oct '10

15 Oct '10

All test machines are CentOS 5.5 (RHEL subscriptions purchased). We've had NFS3 storage working fine and decided to try NFS4. We can mount an NFS4 share on our KVM host, but the SELinux file context on the mountpoint directory is magically changed from virt_image_t to nfs_t. Restorecon refuses to change it back. Adding the mount option context=system_u:object_r:virt_image_t on either server or client doesn't help (option not recognised). What could we be doing wrong? Does NFS4 + KVM work? Are there any 'best practices' references around for using NFS4 for KVM storage? Much of the documentation doesn't appear 100% relevant as we're dealing with a dedicated SAN network with one user (root) and 'always on' sharing, so much of the more complicated authentication and autofs stuff just gets in the way. Thanks Michael Hall IT Communications Officer Alice Springs Town Council mhall(a)astc.nt.gov.au (08) 8950 0561

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[libvirt-users] NFSv4 Storage Pools
by paul.worner＠thomsonreuters.com 14 Oct '10

14 Oct '10

Hi, Is it possible to configure libvirt to use NFSv4 for a pool? I am doing some iptables SNATing and rpc.statd can't handle it. Thanks, Paul

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[libvirt-users] How to rename a domain?
by Ganesh Pagade 14 Oct '10

14 Oct '10

Hi, I am using libvirt Java bindings. How can I rename a domain? Is there an API to do this? Thanks, -Ganesh

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Re: [libvirt-users] Question about use libvirt
by Mike Hall 13 Oct '10

13 Oct '10

Original message: For a new system to develop, I need to know if I can use libvirt for to get (listen) the information that pass trought the lan (vlan) of the each VM. Marcela's perfect Spanish: quiero saber si utilizando esta libreria, puedo utilizar alguna función que me permita capturar los mensajes que se envian aplicaciones paralelas de paso de mensajes que se ejecutan en las máquinas virtuales. Mike's imperfect translation: "I need to know if, using this library (libvirt), I can use a function that allows me to capture information sent by applications in parallel to/in addition to information passed by virtual machines" I'm no expert, but I don't think libvirt has access, via virtual networking, to data sent by applications running in virtual machines. My guess is that such data would be accessible in the same way as with physical machines on a physical network (eg tcpdump?). Mike

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Re: [libvirt-users] Fwd: undefining and redefining a Domain from libvirt java bindings
by Osier 13 Oct '10

13 Oct '10

----- "Ravi Pawar" <ravifc(a)gmail.com> wrote: > hi, > > i am trying to undefine a domain by using dm.undefine(); > and then trying to create one with same name is giving me error saying > 'Domain not found: no domain with matching uuid > 'aeae9d4e-17cb-b661-a612-88ac677c28c1' The error is not throwed by "dm.undefine". looked at and tried your test program, it throws error message like: libvir: QEMU error : Domain not found: no domain with matching name 'tt2' Definitely, it's throwed by: dm =conn.domainLookupByName("tt2"); I guess you looked up the domain by "UUID" before.. so it came the error message saying "no domain with matching uuid .....". The error doesn't influnce the program running forward. e.g. Domain dm1 = conn.domainDefineXML(dumpxml); dm1.create(); int id; id = dm1.getID(); System.out.println(id); dm1.undefine(); You will get the domain ID.. I'm not familiar with Java, guess you can catch the error and turn it into a warning message with "Expection Handler". correct me if I'm not right.. :-) - Osier > > i have attached my test program which reproduces the issue. > > please let me know where i am going wrong? > > configuration: libvirt : 0.6.3 > Java Bindings: 0.4.2 > > -- > Thanks & Regards > > Ravi Pawar > > _______________________________________________ > libvirt-users mailing list > libvirt-users(a)redhat.com > https://www.redhat.com/mailman/listinfo/libvirt-users

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[libvirt-users] bootloader_args element
by David Grundy 12 Oct '10

12 Oct '10

I am trying to set the hostname of VMs at boot time and banging my head against the wall. I am using virsh create xen-config.xml to boot a Scientific Linux 5.5 image. I have gone through the libvirt domain xml format at http://libvirt.org/formatdomain.html#elementsResources and I don't see anywhere to set the hostname in there. I am using pygrub for the bootloader and noticed the "bootloader_args" element. Can I pass an argument to the kernel at boot to set the hostname? Can I pass anything to the kernel at boot time? Nothing I have tried seems to work. I have tried sifting through the pygrub code (for lack of documentation) and no luck yet. I think my challenge is with pygrub but any help would be appreciated. I have also posted this at http://lists.xensource.com/archives/html/xen-users/2010-10/msg00143.html and http://www.linuxquestions.org/questions/linux-virtualization-90/setting-hos… but still waiting... Cheers, David

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[libvirt-users] Mac OS X: dyld: lazy symbol binding failed
by Mitchell Hashimoto 12 Oct '10

12 Oct '10

I'm using the Ruby/FFI libvirt library and getting this consistently on Mac OS X: ruby-1.9.2-p0 > FFI::Libvirt.virInitialize dyld: lazy symbol binding failed: Symbol not found: _virThreadInitialize Referenced from: /usr/local/lib/libvirt.dylib Expected in: flat namespace dyld: Symbol not found: _virThreadInitialize Referenced from: /usr/local/lib/libvirt.dylib Expected in: flat namespace Trace/BPT trap I exported DYLD_PRINT_LIBRARIES and it shows that libvirt.dylib is loaded in the process space, but the above still occurs. When I statically link into a C program it works fine, however. Anyone have any idea what could be causing this? If this doesn't get a response, I'll post it to the dev list, since its perhaps relevant to them as well. Thanks, Mitchell

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Re: [libvirt-users] Problems with libvirt / qemu
by Dan Johansson 11 Oct '10

11 Oct '10

Yes, the image contains an OS (it works if I start the guest manually). -- Dan On Monday 11 October 2010 03.41:29 jbuy0710 wrote: > The image contains an OS or not? > If not, you can't choose to boot from disk like "<boot dev='hd'/>" > > 2010/10/10 Dan Johansson <kvm(a)dmj.nu>: > > HI, > > > > I have a small problem with libvirt / qemu. I have created a guest and when I start it from the command-line the guests starts OK, but when I start the guest through libvirt with "virsh start" I get "Booting from Hard Disk... > > Boot failed: not a bootable disk > > No bootable device" > > > > This is the command-line I use to start the guest (which works) > > "cd /var/lib/kvm/Wilmer; /usr/bin/qemu-system-x86_64 --enable-kvm \ > > -net nic,vlan=1,model=rtl8139,macaddr=DE:ED:BE:EF:01:03 -net tap,vlan=1,ifname=qtap13,script=no,downscript=no \ > > -net nic,vlan=3,model=rtl8139,macaddr=DE:ED:BE:EF:03:03 -net tap,vlan=3,ifname=qtap33,script=no,downscript=no \ > > -m 2048 -k de-ch -vnc :3 -daemonize \ > > Wilmer.qcow2" > > > > > > The libvirt XML-file was created using "virsh domxml-from-native qemu-argv" and this is the result of that conversion: > > <domain type='kvm'> > > <name>wilmer</name> > > <uuid>a421968d-0573-1356-8cb7-32caff525a03</uuid> > > <memory>2097152</memory> > > <currentMemory>2097152</currentMemory> > > <vcpu>2</vcpu> > > <os> > > <type arch='x86_64' machine='pc-0.12'>hvm</type> > > <boot dev='hd'/> > > </os> > > <features> > > <acpi/> > > </features> > > <clock offset='utc'/> > > <on_poweroff>destroy</on_poweroff> > > <on_reboot>restart</on_reboot> > > <on_crash>destroy</on_crash> > > <devices> > > <emulator>/usr/bin/qemu-system-x86_64</emulator> > > <disk type='file' device='disk'> > > <source file='/var/lib/kvm/Wilmer/Wilmer.qcow2'/> > > <target dev='hda' bus='ide'/> > > <address type='drive' controller='0' bus='0' unit='0'/> > > </disk> > > <controller type='ide' index='0'> > > <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> > > </controller> > > <interface type='ethernet'> > > <mac address='de:ed:be:ef:01:03'/> > > <script path='no'/> > > <target dev='qtap13'/> > > <model type='rtl8139'/> > > <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> > > </interface> > > <interface type='ethernet'> > > <mac address='de:ed:be:ef:03:03'/> > > <script path='no'/> > > <target dev='qtap33'/> > > <model type='rtl8139'/> > > <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/> > > </interface> > > <input type='mouse' bus='ps2'/> > > <graphics type='vnc' port='5903' autoport='no' listen=''/> > > <video> > > <model type='cirrus' vram='9216' heads='1'/> > > <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/> > > </video> > > </devices> > > </domain> > > > > > > Anyone seeing something obvious that I have missed? > > > > Regards, > > -- > > Dan Johansson, <http://www.dmj.nu> > > *************************************************** > > This message is printed on 100% recycled electrons! > > *************************************************** > > > > _______________________________________________ > > libvirt-users mailing list > > libvirt-users(a)redhat.com > > https://www.redhat.com/mailman/listinfo/libvirt-users > > > -- Dan Johansson, <http://www.dmj.nu> *************************************************** This message is printed on 100% recycled electrons! ***************************************************

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[libvirt-users] Problems with libvirt / qemu
by Dan Johansson 10 Oct '10

10 Oct '10

HI, I have a small problem with libvirt / qemu. I have created a guest and when I start it from the command-line the guests starts OK, but when I start the guest through libvirt with "virsh start" I get "Booting from Hard Disk... Boot failed: not a bootable disk No bootable device" This is the command-line I use to start the guest (which works) "cd /var/lib/kvm/Wilmer; /usr/bin/qemu-system-x86_64 --enable-kvm \ -net nic,vlan=1,model=rtl8139,macaddr=DE:ED:BE:EF:01:03 -net tap,vlan=1,ifname=qtap13,script=no,downscript=no \ -net nic,vlan=3,model=rtl8139,macaddr=DE:ED:BE:EF:03:03 -net tap,vlan=3,ifname=qtap33,script=no,downscript=no \ -m 2048 -k de-ch -vnc :3 -daemonize \ Wilmer.qcow2" The libvirt XML-file was created using "virsh domxml-from-native qemu-argv" and this is the result of that conversion: <domain type='kvm'> <name>wilmer</name> <uuid>a421968d-0573-1356-8cb7-32caff525a03</uuid> <memory>2097152</memory> <currentMemory>2097152</currentMemory> <vcpu>2</vcpu> <os> <type arch='x86_64' machine='pc-0.12'>hvm</type> <boot dev='hd'/> </os> <features> <acpi/> </features> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>destroy</on_crash> <devices> <emulator>/usr/bin/qemu-system-x86_64</emulator> <disk type='file' device='disk'> <source file='/var/lib/kvm/Wilmer/Wilmer.qcow2'/> <target dev='hda' bus='ide'/> <address type='drive' controller='0' bus='0' unit='0'/> </disk> <controller type='ide' index='0'> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> </controller> <interface type='ethernet'> <mac address='de:ed:be:ef:01:03'/> <script path='no'/> <target dev='qtap13'/> <model type='rtl8139'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> </interface> <interface type='ethernet'> <mac address='de:ed:be:ef:03:03'/> <script path='no'/> <target dev='qtap33'/> <model type='rtl8139'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/> </interface> <input type='mouse' bus='ps2'/> <graphics type='vnc' port='5903' autoport='no' listen=''/> <video> <model type='cirrus' vram='9216' heads='1'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/> </video> </devices> </domain> Anyone seeing something obvious that I have missed? Regards, -- Dan Johansson, <http://www.dmj.nu> *************************************************** This message is printed on 100% recycled electrons! ***************************************************

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[libvirt-users] Error while starting the domain "error: monitor socket did not show up.: Connection refused"
by Ravi Pawar 08 Oct '10

08 Oct '10

All, here is my domain xml <domain type='kvm'> <name>tests</name> <uuid>76bc677f-ee5b-ef0b-1d02-72d12785b1d8</uuid> <memory>524288</memory> <currentMemory>524288</currentMemory> <vcpu>1</vcpu> <os> <type arch='x86_64' machine='pc-0.12'>hvm</type> <boot dev='network'/> </os> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>destroy</on_crash> <devices> <emulator>/usr/libexec/qemu-kvm</emulator> <disk type='file' device='disk'> <source file='/var/lib/libvirt/images/testKVM'/> <target dev='hda' bus='ide'/> <address type='drive' controller='0' bus='0' unit='0'/> </disk> <controller type='ide' index='0'/> <interface type='network'> <mac address='52:54:00:a4:0e:ce'/> <source network='default'/> <target dev='vnet0'/> </interface> <input type='mouse' bus='ps2'/> <graphics type='vnc' port='-1' autoport='yes' listen='127.0.0.1' keymap='en-us'/> <video> <model type='cirrus' vram='9216' heads='1'/> </video> </devices> </domain> my host is RHEL 6 beta. i don't have any clue where i am going wrong in the configuration of the host or configuration of the domain. -- Thanks & Regards Ravi Pawar

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[libvirt-users] Ruby-libvirt and openAuth
by Jonathan Kelley 06 Oct '10

06 Oct '10

Hello, It looks like the Ruby bindings do not support virConnectOpenAuth. Is this true? If so, is there any reason why? or plans to? Thanks, Jon

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[libvirt-users] Monitoring and statistics through libvirt
by Tomi 06 Oct '10

06 Oct '10

Hi folks, is it possible to monitor and gather statistics in realtime (CPU, memory, HDD, network, ... - something like dstat) of guest systems with libvirt through console from host system (KVM based)? If yes, do those guests need to be created through libvirt? Thanks for your help and time.

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[libvirt-users] [PATCH] Re: Python XML parsing of domain descriptions?
by James M Leddy 06 Oct '10

06 Oct '10

rp.gs.com> Jon, Would you try with this patch? diff -c libvirt-0.6.3/docs/schemas/domain.rng libvirt-0.6.3.updateschema/docs/schemas/domain.rng *** libvirt-0.6.3/docs/schemas/domain.rng 2010-07-23 12:44:45.000000000 -0400 --- libvirt-0.6.3.updateschema/docs/schemas/domain.rng 2010-10-05 14:17:16.700561725 -0400 *************** *** 150,155 **** --- 150,156 ---- </attribute> <attribute name="machine"> <choice> + <value>rhel5.4.0</value> <value>xenfv</value> <value>pc</value> <value>isapc</value> -- James M. Leddy Technical Account Manager Red Hat Inc.

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[libvirt-users] KVM Live Migration
by Mike Hall 06 Oct '10

06 Oct '10

We have the following test environment: 2 x CentOS 5.5 KVM virtual hosts 2 x CentOS 5.5 network storage boxes with NFS shares on LVs on DRBD (primary/secondary, no HA, just replication). We have installed both CentOS and Win7 guests which live migrate almost instantly between hosts using Virt Manager (or virsh migrate). The problem is that the guests does not retain their running state after migration, but instead arrive on the new host in "reboot after unclean shutdown" state. The migrated machines also lose IP connectivity (static IP) upon migration to new host, but regain it on migration back to original host. So, live migration in this case isn't producing the expected results (a running, usable guest). Same results using "migrate offline" option and pausing machines before migration. Any pointers on what we're doing wrong? Is there a need for us to implement hook scripts? Michael Hall IT Communications Officer Alice Springs Town Council mhall(a)astc.nt.gov.au (08) 8950 0561

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[libvirt-users] Mounting an lvm
by Dale Amon 05 Oct '10

05 Oct '10

I converted a system disk from a virtualbox VM and added to the config on a qemu VM. All seems well until I try to mount it. The virtual machine shows data for the disk image using commands like: pvs lvs lvdisplay xena-1 but there is no /dev/xena-1/root to be mounted. I also cannot seem to figure out whether the lvm related modules are available for the virtual machine kernel. Has anyone else tried playing this game?

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[libvirt-users] Puppet Module for Virtualization Management
by Carla Araujo 05 Oct '10

05 Oct '10

Hi all! Puppet [0] is an Open Source data center automation and configuration management framework. Puppet provides system administration with a simplified platform that allows for consistent, transparent, and flexible system management. Puppet can be extended with new modules, which are reusable, sharable units of Puppet code. This year, during the Google Summer of Code [1], I developed a new Puppet's module: Puppet-virt. Puppet-virt [2] provides a new type that allows the administrator to deploy and manage virtual machines using r *uby-libvirt* . At first, only Xen fullyvirtualization, Xen paravirtualization, KVM and OpenVZ are supported. If you have any suggestion or contribution, fell free to contact me and/or fork the repository at github. :) Regards, Carla Souza [0] http://www.puppetlabs.com/ [1] http://socghop.appspot.com/ [2] http://github.com/carlasouza/puppet-virt

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[libvirt-users] LXC
by Papp Tamás 05 Oct '10

05 Oct '10

hi All, I'm new to this list and also not a professional libvirt user:) I'm trying to use it for running a container. This is my config: <domain type='lxc'> <name>test</name> <uuid>d3667da2-061a-7b20-a29c-3afc798a257e</uuid> <memory>500000</memory> <currentMemory>500000</currentMemory> <vcpu>1</vcpu> <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>destroy</on_crash> <devices> <emulator>/usr/lib/libvirt/libvirt_lxc</emulator> <filesystem type='mount'> <source dir='/data/lxc/test/rootfs'/> <target dir='/'/> </filesystem> <interface type='bridge'> <mac address='52:54:00:b8:a7:80'/> <source bridge='br1'/> <target dev='veth0'/> </interface> <console type='pty'> <target type='serial' port='0'/> </console> </devices> </domain> It's up and running after start: 3141 ? Ss 0:00 /usr/lib/libvirt/libvirt_lxc --name test --console 107 --background --veth veth1 3148 pts/0 Ss+ 0:00 \_ /sbin/init 3158 ? S<s 0:00 \_ udevd --daemon 3641 ? S< 0:00 | \_ udevd --daemon 3643 ? S< 0:00 | \_ udevd --daemon 3690 ? Sl 0:00 \_ rsyslogd -c4 3703 ? Ss 0:00 \_ /usr/sbin/sshd 3730 ? Ss 0:00 \_ cron 3767 ? Ssl 0:00 \_ /usr/sbin/nscd 3818 ? Ss 0:00 \_ /usr/sbin/munin-node 3989 ? Ss 0:00 \_ /usr/lib/postfix/master 3996 ? S 0:00 | \_ pickup -l -t fifo -u -c 3997 ? S 0:00 | \_ qmgr -l -t fifo -u 3998 ? Ss 0:00 \_ /sbin/getty -8 38400 tty1 I'm trying to connect to the console: $ virsh --connect=lxc:/// console test Connected to domain test Escape character is ^] And it got off: $ virsh --connect=lxc:/// list --all Id Name State ---------------------------------- - test shut off /var/log/libvirt/lxc/test.log: 23:17:13.463: error : lxcFdForward:231 : read of fd 7 failed: Input/output error The system is Ubuntu 10.10 beta, 2.6.35-22-server and libvirt 0.8.3-1ubuntu14. What's wrong? I am out of idea. Thank you, tamas

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[libvirt-users] Updates to cucmber-vhost - guineapigs wanted! :)
by Matthew Macdonald-Wallace 04 Oct '10

04 Oct '10

Hi all, For those of you that are using cucumber for Continuous Integration or similar I've created a set of steps that enable you to use cobbler and cucumber to auto-provision using Libvirt. I've just made some changes to the code however I don't have access to all the hardware/software required to test it fully. If you are able to, please check out the code from http://tinyurl.com/virtcuke (my github repo) and test, posting bugs against the project. Thanks in advance, Matt

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[libvirt-users] virt-xml-validate b0rked?
by Stanley, Jon [Tech] 04 Oct '10

04 Oct '10

It seems that virt-xml-validate doesn't validate what *has* to be valid XML, that generated by virsh dumpxml against a running domain: [root@etc752365a ~]# virsh list Id Name State ---------------------------------- 2 rhel55 running 3 rhel53 running [root@etc752365a ~]# virsh dumpxml rhel55 > foo.xml [root@etc752365a ~]# virt-xml-validate foo.xml foo.xml:8: element type: Relax-NG validity error : Invalid attribute arch for element type foo.xml:9: element boot: Relax-NG validity error : Element os failed to validate content foo.xml:8: element type: Relax-NG validity error : Error validating value foo.xml:8: element type: Relax-NG validity error : Element type failed to validate content foo.xml:1: element domain: Relax-NG validity error : Invalid sequence in interleave foo.xml:1: element domain: Relax-NG validity error : Element domain failed to validate content foo.xml fails to validate Is there something that I'm doing wrong here? This is the libvirt that comes with RHEL5.5

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[libvirt-users] Anyone has new libvirt java binding jar, i want the latest one. i dont have the build env at my end.
by Ravi Pawar 04 Oct '10

04 Oct '10

-- Thanks & Regards Ravi Pawar

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[libvirt-users] Import/Export Support
by Mitchell Hashimoto 04 Oct '10

04 Oct '10

Hello, I'm looking into using libvirt in the near future, however an important part of our workflow is the ability to import and export virtual machines (in VirtualBox). Does libvirt provide an easy way to do this? I couldn't find anything obvious on the API reference. Thanks, Mitchell

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[libvirt-users] OVF => XML?
by Mitchell Hashimoto 01 Oct '10

01 Oct '10

Hello, Does libvirt provide any easy way to convert an OVF to libvirt XML specification? I noticed "virt-convert" but I'm not sure what the status of that project is or if this is officially supported. Has anyone successfully done this before and if so, what troubles did you run into? Thanks, Mitchell

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[libvirt-users] Python XML parsing of domain descriptions?
by Stanley, Jon [Tech] 01 Oct '10

01 Oct '10

Does anyone know of a way to parse the libvirt XML into usable python data structures? Ideally, it would be something like foo['domain']['devices']['bridge'][0]['target'] or something of the sort. What I'm looking to accomplish is to figure out which tap interface goes with a specific domain. I'm not keen on parsing XML to get that mapping, is there a better way to do it without parsing XML?

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[libvirt-users] undefining and redefining a Domain
by Roberto Attias (rattias) 01 Oct '10

01 Oct '10

<resending as I don't think I was in the mailing list yet when I sent first time... apologies if you receive this twice> Hello, I'm facing some strange behavior, and I hope you can provide a clarification. Consider the following code: virDomainPtr dom = virDomainLookupByName(virt, domain_name); if (dom) { printf("domain already defined...\n"); if (virDomainUndefine(dom)) printf("...unable to undefine!!!\n"); else { printf("...undefined."); free(dom); } } dom = virDomainDefineXML(virt, SOME_XML); if (dom != NULL) { const char *name = virDomainGetName(dom); printf("NAME IS NOW: %s\n", name); } else printf("dom is NULL!\n"); When executed the first time, the code correctly defines the domain, and prints: defining domain test2-vm libvir: QEMU error : Domain not found: no domain with matching name 'test2-vm' NAME IS NOW: test2-vm If executed a second time with the same SOME_XML when the domain is already defined, it prints: defining domain test2-vm domain already defined... libvir: Domain error : invalid domain pointer in virDomainGetName undefining......undefined.NAME IS NOW: (null) Not only the name is null, but the domain can't be started. What is the correct way to undefined programmatically a domain that is already defined? Why is the second virDomainDefineXML() returining a pointer (as opposed to null), but the pointed object seem to be invalid? Thanks, Roberto

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