- Users - libvirt List Archives

[libvirt-users] Mapping physical interface to a container
by Peter Steele 22 Apr '16

22 Apr '16

In the "other" LXC project (linuxcontainers.org) you can map a host's physical ethernet interface to a container, e.g. lxc.network.type = phys lxc.network.flags = up lxc.network.link = eth1 lxc.network.name = eth1 Is there an equivalent option for doing this with libvirt lxc? Peter

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[libvirt-users] uefi built from tiancore via edk2 can't persist boot changes
by jsl6uy js16uy 20 Apr '16

20 Apr '16

Apologies if this has been gone over, but I believe I have checked the intertubes more than a bit..... I am using libvirt and have vms booting under an OVMF.fd to use an efi firmware. I can create vms, linux ubuntu, and they will boot up. However, everytime I reboot am I dropped into the default efi shell provide by the tianocore build. Then I must walk the FS to the booting efi app and run, in this case grubx64.efi, to actually finish booting the host. I had tried adding boot entries with efibootmgr within the OS and also bcfg with the efi shell. I get no errors when adding an entry, and the new entry shows up and I can manipulate the entry i.e. set it to next boot and the like. Soon as I reboot I get dumped back to efi shell. Am I missing something? Are the var changes not being stored? Is there someplace to look for an error perhaps? I also can use the same efi bootloader under libvirt to boot a hybrid iso. location of the efi application on the hybrid iso is /EFI/boot/bootx64.efi. Drops me right into my grub menu, after falling thru from EFI FLOPPY1 and EFI FLOPPY2 to EFI DVD So since that was/is working, tried adding that to my efi partition so it has /EFI/boot/bootx64.efi. The thinking being that since I can't add an entry, I will setup for the "known" efi boot path. Of course that didn't work either I am on arch linux: Linux X 4.4.5-1-ARCH #1 SMP PREEMPT Thu Mar 10 07:38:19 CET 2016 x86_64 GNU/Linux local/libvirt 1.3.2-3 API for controlling virtualization engines (openvz,kvm,qemu,virtualbox,xen,etc) local/libvirt-python 1.3.1-1 libvirt python binding UEFI: Shell> ver UEFI Interactive Shell v2.1 EDK II UEFI v2.50 (EDK II, 0x00010000) for this host....my nvram setting look like <os> <type arch='x86_64' machine='pc-i440fx-2.5'>hvm</type> <loader readonly='yes' type='pflash'>/home/xyz/OVMF.fd</loader> <nvram template='/usr/share/OVMF/OVMF_VARS.fd'>/var/lib/libvirt/qemu/nvram/X_VARS.fd</nvram> <boot dev='hd'/> </os>

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[libvirt-users] ssh-askpass in libvirt
by Alex Roithman 20 Apr '16

20 Apr '16

It seems, that libvirt use system environments for finding the ask-pass application. You can to tell me this variables? Or libvirt uses another mechanism for call to ssh-askpass application?

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[libvirt-users] Create multiple domains from single saved domain state (is UUID/name fixed?)
by Jonas Finnemann Jensen 20 Apr '16

20 Apr '16

Hi, I would like to save a running domain (ie. disk + memory) and be able to restore it multiple times creating duplicates of the orignal domain all starting from the same state. Use case: I'm building a task-processing system for use in a CI flow. I want to run multiple VMs in parallel using the same image (always starting from the same state). And to avoid needlessly booting between each task, I would like to save (and distribute) the domain state, so that I just restore from memory. However, I can't seems to change the UUID or the name of a domain once it is saved. Nor do I seem able to rename a domain while it is running. I can obviously duplicate both the disks and the file to which I saved the domain state using "virsh save". But I seem unable to rename before I restore.. Any ideas? Could I do this with snapshots? I suspect not since I see virDomainSnapshotRedefinePrep() calling virDomainDefCheckABIStability which raises the error here: https://fossies.org/dox/libvirt-1.3.3/domain__conf_8c_source.html#l17991 Out of curiosity does anyone know what horrors might befall me if I were to remove the lines protecting against name and UUID changes? Then compile my own libvirt... The comment in the code says name can be changed, but I'm guessing I would have to change the UUID too. Does anyone see how that would create issues? I'm not sure how libvirt uses the UUID internally. -- Regards Jonas Finnemann Jensen.

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[libvirt-users] this function is not supported by the connection driver: virDomainCoreDump
by Alex Font 18 Apr '16

18 Apr '16

Hi, I'm facing problems trying to get a full dump of a VM machine on ESXi 6.0, using libvirt 1.3.3. When I try to do: virsh$: dump vm_machine dump.dmp I get the following error: this function is not supported by the connection driver: virDomainCoreDump Is there any way to get dumps of VM's? Thanks in advance. Alex

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[libvirt-users] Make disk "unaffected by snapshots"
by Basin Ilya 17 Apr '16

17 Apr '16

Hi. Is it possible to make a virtual disk unaffected by snapshots just like writethrough disks in VBox? I tried raw with shareable flag, but snapshot creation fails with: "internal snapshot for disk vdb unsupported for storage type raw".

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[libvirt-users] Can libvird use iSCSI direcly?
by Basin Ilya 15 Apr '16

15 Apr '16

Hi. I was expecting that qemu-kvm process would connect directly to iSCSI server, but https://libvirt.org/storage.html#StorageBackendISCSI says that it wants symlinks in `/dev/disk/by-path` . That suggests it relies on Linux iSCSI client that will act as mediator and create block devices. So is "iSCSI volume pools" just a convenience thing giving no performance gain compared to attaching block devices to my guest?

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[libvirt-users] locked out after preseed install
by Mario Gummies 14 Apr '16

14 Apr '16

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[libvirt-users] How to optimize for IBM db2?
by Basin Ilya 14 Apr '16

14 Apr '16

Hi. I have performance problems with IBM DB2 10.5 server on KVM guest: [db2inst1@wc8ws-auth ~]$ time db2 create db test DB20000I The CREATE DATABASE command completed successfully. real 7m46.155s user 0m0.022s sys 0m0.027s It takes 30 seconds to create a database on an image mounted with -oloop. I think it's because db2 uses O_DIRECT to ensure consistency. I also think that O_DIRECT is not propagated to host with default cache modes in VM settings. The real problem is: when guest writes data in small blocks, host CPU becomes a bottleneck. I hava a relatively old 24-core Xeon. Host `top` shows 130% CPU usage by qemu-kvm, when I run the following command: [root@wc8ws-auth ~]# </dev/zero timeout -sINT 30s dd iflag=fullblock oflag=direct conv=notrunc of=./bigfile bs=8192 140384+0 records in 140384+0 records out 1150025728 bytes (1.2 GB) copied, 29.9992 s, 38.3 MB/s I tried all buses, cache modes and IO modes; "Cache mode=none" is slower, others are almost equal. I moved from image file to LVM. This raised the speed from 16M to 38M. I also tried VirtualBox, but it's neither faster, nor slower, and it eats CPU too. -- -------------------------------------------------------------------------------- Kind regards, Ilya Basin software engineer Reksoft Skype: basin_ilya phone +7(812)324-24-40*553

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[libvirt-users] how to list and kill existing console sessions to VMs?
by Francesco Romani 14 Apr '16

14 Apr '16

Hi everyone, If a VM is configured to have a console attached to it, like using http://libvirt.org/formatdomain.html#elementCharConsole Libvirt offers access to VM serial console's using the virDomainOpenConsole API[1] However, I didn't find a way to 1. list the existing connections to the console 2. kill an existing connection - without reconnecting using VIR_DOMAIN_CONSOLE_FORCE[2] Am I missing something? How can I do that? Rationale for my request oVirt [3] offers a management interface for VMs, and we have recently integrated user-friandly VM serial console access [4] in the system; in the future release we want to enhance the administation capabilities allowing to check existing connections and to terminate them (maybe because it got stuck). +++ [1] http://libvirt.org/html/libvirt-libvirt-domain.html#virDomainOpenConsole [2] http://libvirt.org/html/libvirt-libvirt-domain.html#VIR_DOMAIN_CONSOLE_FORCE [4] http://www.ovirt.org/ [5] https://www.ovirt.org/develop/release-management/features/engine/serial-con… et. al. -- Francesco Romani RedHat Engineering Virtualization R & D Phone: 8261328 IRC: fromani

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