November 2018 - Users - libvirt List Archives

[libvirt-users] Problems getting nwfilter to work
by Marc 08 Nov '18

08 Nov '18

Hi folks, I'm using libvirt 3.9.0 running under CentOS 7.5. I want the guests, which are all within the same subnet (e.g. 10.0.0.x.), only talk to their default gateway (e.g. 10.0.0.1) but to each other. This is caused by a design issue of our network platform. I set up a filter rule and attached it to the interface of a guest using nwfilter-define: <filter name='private_ip' chain='ipv4'> <uuid>foobar</uuid> <rule action='accept' direction='out' priority='100'> <ip srcipaddr='$IP' dstipaddr='10.0.0.1'/> </rule> <rule action='accept' direction='in' priority='110'> <ip srcipaddr='10.0.0.1' dstipaddr='$IP'/> </rule> <rule action='drop' direction='inout' priority='500'> <all/> </rule> </filter> t simply doesn't work. The guest can talk to the other guests within the same subnet. All guests are connected to a bridge interface. The IP of the guest interface is defined in the guests' xml file. Is there any additional kernel module to load? The module br_netfilter is already loaded and /proc/sys/net/bridge/bridge-nf-call-iptables is set to 1. After hours of googling and testing I still couldn't find a solution. Please help! Thank you very much in advance Marc

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[libvirt-users] How to find out what is deleting my vms
by Andy Gibbs 08 Nov '18

08 Nov '18

Hi, I have a CentOS-7 server running KVM but also oVirt. Recently, following updates, VMs not handled by oVirt have been deleting themselves after they shut down. Previously to this, I have not had any problems of this nature. I cannot say whether the problem is coming from oVirt updates or not. I am creating a VM using "virsh define myvm.xml" on the server, starting it through virt-manager on my local PC, performing work inside the VM and then closing down the operating system inside the VM, and then once it has completed shutting down it shows "Shutoff" as the status in virt-manager and then maybe 5 seconds later it disappears from the list entirely and has been deleted. To start the VM again, requires "virsh define myvm.xml" to be run again. What I cannot determine is **why** the VM is deleted. I am using "virsh define" which I understand should create a persistent VM, and I have enabled "audit_level=2" and "audit_logging=1" in libvirtd.conf but can't see anything helpful in the log output (although maybe I don't know what I'm looking for). Is anyone, please, able to help me work out what is deleting my VMs once they shut down ... and, if possible, why?! Many, many thanks, Andy

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[libvirt-users] timeout on VM actions prone to hang
by Nikola Ciprich 07 Nov '18

07 Nov '18

Hi fellow libvirt users, I'd like to ask, whether somebody possibly dealt with similar problem we're hitting.. Some of libvirt VM operations (ie fs freeze) are prone to hang for long time, in case the guest agent is in some bad state.. My question is, if it's possible to set some timeout for such operations, or we have to deal with it ie with separate thread and some timers? we're using python libvirt bindings.. I'll appreciate any advice BR nik -- ------------------------------------- Ing. Nikola CIPRICH LinuxBox.cz, s.r.o. 28.rijna 168, 709 00 Ostrava tel.: +420 591 166 214 fax: +420 596 621 273 mobil: +420 777 093 799 www.linuxbox.cz mobil servis: +420 737 238 656 email servis: servis(a)linuxbox.cz -------------------------------------

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[libvirt-users] libvirt with persistent device names
by Jan Marquardt 07 Nov '18

07 Nov '18

Hi, I am trying to create a logical volume storage pool with persistent device names for the block devices, because I can't/don't want to ensure that /dev/sd* names are persistent through reboots. virsh # pool-define-as web2067 logical - - /dev/disk/by-path/pci-0000:18:00.0-scsi-0:2:2:0 web2067 /dev/web2067 virsh # pool-build web2067 These two steps work as expected and the pv and the vg get created, but when I try to start the pool I get the following error: virsh # pool-start web2067 error: Failed to start pool web2067 error: unsupported configuration: cannot find any matching source devices for logical volume group 'web2067' If I do the same steps just with /dev/sdX instead of /dev/disk/by-path/..., the pool gets created correctly. This looks like a bug for me or am I wrong? If this is the case, is this and known issue and fixed in later versions? I am running Ubuntu 18.04 with libvirt in version 4.0.0. Best Regards Jan

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[libvirt-users] Questions regarding migration from QEMU to libvirt
by Rodrigo Siqueira 06 Nov '18

06 Nov '18

Hi, My colleagues and I have a set of scripts that we use to automate our daily tasks related to the Linux Kernel. As a result, most of our code relies on the QEMU features; and recently we decided use libvirt instead of QEMU. However, we have some questions, and I would like to know if someone could help us. Follows: 1) Import our QEMU images with virsh Currently, we import the QEMU VMs with virt-install. Is it possible to automatically discover the distro variant of a QEMU image in order to use it in the “--os-variant” option? Here is how we register a VM: https://github.com/rodrigosiqueira/kworkflow/pull/23/files#diff-70617d452b0… 2) The requirement of sudo to create a network When we register our VM, we want to keep the ssh working well. However, every time we register a VM we create a new network bridge as a result it requires sudo. Is it possible to avoid this? Or at least make this a single action? Here is how we handled this: * The code for register: https://github.com/rodrigosiqueira/kworkflow/pull/23/files#diff-70617d452b0… * The configuration file that we adopted as a default: https://github.com/rodrigosiqueira/kworkflow/pull/23/files#diff-d8c16482496… 3) When using libvirt it changes the owner of our image If we try to use libvirt, it changes the ownership of our QEMU images (root). We fixed it by changing the file “/etc/libvirt/qemu.conf”, and switch the option dynamic_ownership to “0”. What is the impact of that change? Is it dangerous? There is a way to avoid this change? Finally, here is the full code of the libvirt part: https://github.com/rodrigosiqueira/kworkflow/pull/23/files Thanks Best Regards -- Rodrigo Siqueira http://siqueira.tech Graduate Student Department of Computer Science University of São Paulo

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[libvirt-users] Hello World
by Ameya Sinha 05 Nov '18

05 Nov '18

Hello Everyone! I'm Ameya Sinha, a student, and I wanted to contribute to the libvirt organization. I have read through the contributing guidelines ( https://libvirt.org/contribute.html) and contributor guidelines ( https://libvirt.org/hacking.html) Can someone suggest how should I proceed from here? Thank You, Ameya Sinha

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[libvirt-users] Windows guest skipping chkdsk if using Spice display
by Gionatan Danti 05 Nov '18

05 Nov '18

Hi all, as per subject, when a Windows guest using a Spice display is rebooted with a planned chkdsk, the consistency check is always skipped. It seems that the Spice display issues some "phantom" keystrokes, which are then intended by Windows as the "skip chkdsk at boot" signal. I tried to use a Spice display with no additional features (ie: USB redirection), but to no avail. To workaround the problem I must use a VNC display, which is less featureful than the Spice one. My system and package versions are: CentOS 7.5 x86-64 spice-gtk3-0.34-3.el7_5.1.x86_64 spice-server-0.14.0-2.el7_5.4.x86_64 spice-glib-0.34-3.el7_5.1.x86_64 libvirt-3.9.0-14.el7_5.7.x86_64 qemu-kvm-ev-2.10.0-21.el7_5.4.1.x86_64 It seems I am not the only one experiencing this problem: http://seifesrants.blogspot.com/2016/07/ghost-keystrokes-with-libvirt-kvm-s… Any suggestion? Thanks. -- Danti Gionatan Supporto Tecnico Assyoma S.r.l. - www.assyoma.it email: g.danti(a)assyoma.it - info(a)assyoma.it GPG public key ID: FF5F32A8

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[libvirt-users] How to change the default connection of 'virsh' tool from 'qemu' to 'xen' ?
by Minjun Hong 02 Nov '18

02 Nov '18

Hi. Thanks to help of this mailing list (especially Jim Fehlig), I have finished setup of libvirt. However, there is something weird. It is that I installed libvirt on 5 servers but the default connection of one of them is 'qemu:///' even if those of the others are all 'xen:///'. I searched how to change it but, I only found a bypass adding " LIBVIRT_DEFAULT_URI='xen:///' " in my .bashrc file. Currently, value of the variable (LIBVIRT_DEFAULT_URI) is set to 'qemu:///'. Since the bypass makes the virtualization type of the server visible 'qemu' to the open stack, I have to change libvirt configuration. I also checked some configure files under '/etc/libvirt', such as libvirt.conf, libvirtd.conf and libxl.conf. But I have no idea, how and what to change. Please give me some advise. It will be a big help for me. Thanks.

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[libvirt-users] Read CPU Performance Statistics
by Hana Yehia 01 Nov '18

01 Nov '18

Hi, I am in need for a help for how to use libvirt in python to read the the guest VMs performance statistics like cache hit and miss rates , I have KVM- Qemu as a virtual machine manager , I am looking for a sample code or the instructions needed to help me read these statistics . Thanks, hana

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