May 2012 - Users - libvirt List Archives

[libvirt-users] some problem with snapshot by libvirt
by xingxing gao 21 Nov '14

21 Nov '14

Hi,all,i am using libvirt to manage my vm,in these days i am testing the libvirt snapshot ,but meet some problem: the snapshot was created from this command: snapshot-create-as win7 --disk-only --diskspec vda,snapshot=external --diskspec hda,snapshot=no but when i tried to revert from the snapshot which created from the above command ,i got error below: virsh # snapshot-revert win7 1338041515 --force error: unsupported configuration: revert to external disk snapshot not supported yet version: virsh # version Compiled against library: libvir 0.9.4 Using library: libvir 0.9.4 Using API: QEMU 0.9.4 Running hypervisor: QEMU 1.0.93

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[libvirt-users] virsh list not working with xen 4
by Rogério Vinhal Nunes 21 Sep '12

21 Sep '12

Hi, I'm having some trouble to get libvirt to show the correct power state of my virtual machines. I'm using Ubuntu 10.04 + Xen 4.1.1 + libvirt 0.8.8. virsh list --all only shows turned off machines registered in xend. If I turn them on, they just "disappear", and when I start machines directly from xml, they just doesn't appear at all. Libvirt is correctly connecting to xen as I can use the other commands fine, just the list option doesn't seem to work at all. What can I do to change that? # virsh version Compiled against library: libvir 0.8.8 Using library: libvir 0.8.8 Using API: Xen 3.0.1 Running hypervisor: Xen 4.1.0

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[libvirt-users] qemu-kvm fails on RHEL6
by sumit sengupta 02 Jul '12

02 Jul '12

Hi, When I'm trying to run qemu-kvm command on RHEL6(linux kernel 2.6.32) then I get following errors which I think related to tap devices in my setup. Any idea why is that? bash$ LC_ALL=C PATH=/sbin:/usr/sbin:/bin:/usr/bin QEMU_AUDIO_DRV=none /usr/libexec/qemu-kvm -S -M rhel6.2.0 -enable-kvm -m 512 -smp 1,sockets=1,cores=1,threads=1 -name instance-00000027 -uuid a93aeed9-15f7-4ded-b6b3-34c8d2c101a8 -nodefconfig -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/instance-00000027.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc -no-shutdown -kernel /home/sumitsen/openstack/nova/instances/instance-00000027/kernel -initrd /home/sumitsen/openstack/nova/instances/instance-00000027/ramdisk -append root=/dev/vda console=ttyS0 -drive file=/home/sumitsen/openstack/nova/instances/instance-00000027/disk,if=none,id=drive-virtio-disk0,format=qcow2,cache=none -device virtio-blk-pci,bus=pci.0,addr=0x4,drive=drive-virtio-disk0,id=virtio-disk0 -netdev tap,fd=26,id=hostnet0 -device rtl8139,netdev=hostnet0,id=net0,mac=fa:16:3e:15:84:3e,bus=pci.0,addr=0x3 -chardev file,id=charserial0,path=/home/sumitsen/openstack/nova/instances/instance-00000027/console.log -device isa-serial,chardev=charserial0,id=serial0 -chardev pty,id=charserial1 -device isa-serial,chardev=charserial1,id=serial1 -usb -device usb-tablet,id=input0 -vnc 127.0.0.1:0 -k en-us -vga cirrus -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x5 char device redirected to /dev/pts/1 qemu-kvm: -netdev tap,fd=26,id=hostnet0: TUNGETIFF ioctl() failed: Bad file descriptor TUNSETOFFLOAD ioctl() failed: Bad file descriptor qemu-kvm: -append root=/dev/vda: could not open disk image console=ttyS0: No such file or directory [sumitsen@sorrygate-dr ~]$ rpm -qa qemu-kvm qemu-kvm-0.12.1.2-2.209.el6.x86_64 Let me know if you need any other info. Thanks, Sumit

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[libvirt-users] [Fwd: error: this function is not supported by the connection driver : virConnectNumOfStoragePool]
by Onkar 05 Jun '12

05 Jun '12

Hello All, Any idea on this issue ? Regards, Onkar -------- Forwarded Message -------- From: Onkar <kernzap(a)gmail.com> To: libvir-list <libvir-list(a)redhat.com> Subject: error: this function is not supported by the connection driver : virConnectNumOfStoragePool Date: Wed, 30 May 2012 21:29:42 +0530 Hello, I configured libvirt like this ./configure --prefix=/ --exec-prefix=/usr/ --libdir=/usr/lib64/ --with-storage-dir --with-storage-dir --with-storage-dir --with-storage-dir --with-storage-dir --with-storage-dir --with-storage-dir --with-storage-dir --with-qemu --with-libvirtd --with-selinux --with-network --with-libblkid and then, make -j4 make install and then # virsh list --all Id Name State ---------------------------------------------------- - vm1 shut off # virsh pool-list --all error: Failed to list active pools error: this function is not supported by the connection driver: virConnectNumOfStoragePools getting this error , any clues on why is this error ? Regards, Onkar

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[libvirt-users] converting save/dump output into physical memory image
by Andrew Tappert 04 Jun '12

04 Jun '12

A lot of people in the security community, myself included, are interested in memory forensics these days. Virtualization is a natural fit with memory forensics because it allows one to get access to a guest's memory without having to introduce any extra software into the guest or otherwise interfere with it. Incident responders are particularly interested in getting memory dumps from systems they're investigating. Virsh has "save" and "dump" commands for storing the state of a guest to a file on disk, but memory of KVM guests doesn't get saved in the "standard" input format for memory forensics tools, which is a raw physical memory image. (This is what you'd get via the classical "dd /dev/mem" approach or the contemporary equivalent using the crash driver; and VMware Server and Workstation produce .vmem files, which are such raw physical memory images, when a guest is paused or snapshotted.) In order to analyze the memory of Libvirt/KVM guests with my Linux memory forensics software, Second Look, I've created a tool for converting Libvirt-QEMU-save files (output of virsh save command) or QEMU-savevm files (output of virsh dump command) to raw physical memory images. I've got a basic working capability, though I'm still tracking down some problems with a guest allocated 8GB RAM--not all the memory seems to be present in the save or dump file. And I haven't tested very extensively yet, version support is limited to what I myself am currently running, etc. I'd like to know if this is a capability that others are interested in. Is this something that would be of interest to the Libvirt project if I were to contribute the code, or to the KVM project, or do you think it best exists as a separate project? I've also got a proof-of-concept tool for converting hibernate images to raw physical memory images. Perhaps a collection of tools for converting various memory dump formats would be a good project. Anyone else interested in this kind of stuff? As an author of commercial memory forensics software I've got a vested interest in availability of good memory acquisition capabilities. But there are a number of people working on FOSS Linux memory analysis tools, too... Andrew

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[libvirt-users] NPIV setup?
by Jason Price 01 Jun '12

01 Jun '12

I'm missing something. The purpose of NPIV (as I understand it) is to give a guest OS an HBA that it can scan, play with new luns, etc all without making changes to the physical server(s) the guest is living in currently. However, I can't find a way to either have the guest's XML config create the HBA or for the physical server to successfully GIVE the HBA to the guest. I can give disks all day long, but I can't give the HBA to the guest. It seems like libvirt and virsh can only create the vHBA on the physical box, which defeats the purpose of working with NPIV then... I can just present the same luns to the REAL WWPNs of the physical boxes that need access, setup multipathd to give /dev/mapper names in a consistent manner, and give the raw disks to the guests. I really want to get the physical KVM servers out of the 'storage management' game aside from the basic OSes of the guests. How can I do that? (or am I missing something?) --Jason

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[libvirt-users] win-xp guest after reboot: could not open disk image /dev/sr0: mo medium found and extreme sluggisch
by Ekkard Gerlach 30 May '12

30 May '12

Hi, win-xp won't boot after installation. The CD is needed to boot from. How can I convince win-xp to boot? That's what I did: ================== I installed win-xp guest on debian squeeze: # virt-install --connect qemu:///system --name winxp-prof --ram 1024 \ --disk path=/dev/vg-levo/winxp-kvm,size=10 \ --network bridge:br0 --vnc --os-variant winxp --cdrom /dev/sr0 /dev/vg-levo/winxp-kvm is a lvm (logical volume, 10GB) Installation worked, but was extrem slow. Machine: Lenovo B560, core i3, 6 GB RAM. WinXP made a normal reboot after installation, I ejected install cd, then: virt-manager output: Error starting domain: internal error Process exited while reading console log output: chard device redirected to /dev/pts/2 qemu: could not open disk image /dev/sr0: mo medium found So I inserted the CD and a black blanc screen appeared. Windows didn't boot. I deleted installation configuration: # virsh undefine winxp-prof I invoked virt-install (see above) once again ... and win-xp is booting ... what a surprise, without installing again after undefine .. ! The reason: the lvm partition was not deleted. WinXP now always needs a CD to boot and is extreme sluggisch. Right mouse click lasts about one minute! tia Ekkard

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[libvirt-users] Virtual Machines Stay Off If Rebooted
by Andrew Martin 30 May '12

30 May '12

Hello, I am using libvirt on Ubuntu 10.04 Server and the following versions of these packages: libvirt-bin, libvirt0, python-libvirt - 0.7.5-5ubuntu27.22 qemu-kvm 0.12.3+noroms-0ubuntu9.18 Recently, when restarting a VM (either by issuing "sudo reboot" on a Linux guest or choosing "Restart" from the Start Menu on a Windows guest) the VM shuts down and remains off rather than simply restarting. I cannot test "virsh restart <domain>" on this server as the version of libvirt does not appear to support restarting - see https://bugs.launchpad.net/ubuntu/+source/libvirt/+bug/368962 I do not receive any errors in /var/log when the shutdown occurs. Powering the VM back on works, however I would prefer to have hot restart working so VMs that are automatically rebooted to install updates will come back up automatically. Do you have any suggestions on how to debug this behavior? Thanks, Andrew

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[libvirt-users] How to configure cpu frequency of guest
by hongming 30 May '12

30 May '12

Hi Experts I want to know how to configure cpu frequency of guest. Why it always display "cpu MHz : 3092.974" , If it needs to offer user a KVM guest with 1 GHz cpu using libvirt , How to do it ? Thanks a lot in advance. Hongming

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[libvirt-users] how to store an internal disk snapshot by use
by Rujie Xu 30 May '12

30 May '12

Hello everyone, I am trying to find a way to store an internal disk snapshot and supposed to restore later. Here is the problems I met: 1) when I use SnapshotCreateXML() to create a disk_only snapshot while the domain is inactive, there is an error happened: disk snapshot of inactive domains not implemented yet. I am wondering is there and way I can save the disk_only snapshot when the domain is inactive right now? 2) also use snapshotCreateXML() to create a disk_only snapshot while the domain is active, and use the xml to set the <disk name="hda" snapshot="internal"> there is also an error happened: unsupported configuration: active qemu domains require external disk snapshot; disk hda requested internal 3) when I use snapshotCreateXML() to create a disk_only snapshot using external file, it could be done, but when I try to use revertToSnapshot() to revert this snapshot there is another error happened: revert to external snapshot not supported yet. Is there anyone can help me about this, or we just can't use libvirt to managed the disk snapshot right now? Thanks very much! -- Best Regards, Roger Xu

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Re: [libvirt-users] some problem with snapshot by libvirt
by xingxing gao 29 May '12

29 May '12

sure you can add the list back in, 2012/5/29 Eric Blake <eblake(a)redhat.com>: > On 05/29/2012 09:03 AM, xingxing gao wrote: >> to create snapshot ,I did step below: > > I'd really rather answer this in public; do I have your permission to > add the list back in, or better yet, can you repost to the list? > > Also, the list tends to frown on top-posting. > >>> Did you mean for this to go to the list, so that others may chime in or >>> benefit from the answers? >>> > > > -- > Eric Blake eblake(a)redhat.com +1-919-301-3266 > Libvirt virtualization library http://libvirt.org >

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[libvirt-users] create net if, but not connect
by Sergio Kvjato 29 May '12

29 May '12

Hello, is there a way to create net if but not connect to any bridge? <interface type='ethernet'/> is not work becaue its need to run in root mode not user mode Thanks.

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[libvirt-users] What features of kernel are required to support virDomainGetCPUStats?
by Zhihua Che 29 May '12

29 May '12

Hi, Weeks ago, I developed my app under ubuntu-11.10 (kernel 3.0) with lilbvirt-0.9.10. In my code , I used virDomainGetCPUStats to query cpu usage info of domains, and it worked well. However, today, I port my code to ubuntu-10.04.4 (kernel 2.6.32) with libvirt-0.9.10, I find the function virDomainGetCPUStats can't work and complains "this function is not supported by the connection driver: virDomainGetCPUStats". I guess the kernel difference cause this problem because the libvirt is the same on two operating systems. I wonder what features of kernel are required to support virDomainGetCPUStats? I thought cgroup is a prerequisite. The following are .config files of two kernels. ubuntu-11.10 CONFIG_CGROUP_FREEZER=y CONFIG_CGROUP_DEVICE=y CONFIG_CPUSETS=y CONFIG_PROC_PID_CPUSET=y CONFIG_CGROUP_CPUACCT=y CONFIG_RESOURCE_COUNTERS=y CONFIG_CGROUP_MEM_RES_CTLR=y CONFIG_CGROUP_MEM_RES_CTLR_SWAP=y CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED=y CONFIG_CGROUP_PERF=y CONFIG_CGROUP_SCHED=y CONFIG_FAIR_GROUP_SCHED=y CONFIG_RT_GROUP_SCHED=y CONFIG_BLK_CGROUP=y ubuntu-10.04.4 CONFIG_CGROUP_NS=y CONFIG_CGROUP_FREEZER=y CONFIG_CGROUP_DEVICE=y CONFIG_CPUSETS=y CONFIG_PROC_PID_CPUSET=y CONFIG_CGROUP_CPUACCT=y CONFIG_RESOURCE_COUNTERS=y CONFIG_CGROUP_MEM_RES_CTLR=y CONFIG_CGROUP_MEM_RES_CTLR_SWAP=y CONFIG_CGROUP_SCHED=y CONFIG_FAIR_GROUP_SCHED=y CONFIG_RT_GROUP_SCHED=y CONFIG_MM_OWNER=y As you can see, CPUSET and CPUACCT are enabled in both kernels. So what else features of kernel are required to support virDomainGetCPUStats? harvey

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[libvirt-users] New Bugzilla components for upstream bug reporting
by Daniel P. Berrange 28 May '12

28 May '12

Historically we have told people to report all upstream bugs against Product: Virtualization Tools Component: libvirt We now provide much more than just the core libvirt package though. Thus we have created a large number of new components for reporting upstream bugs against, one for each package we distribute: Component: libvirt-appdev-guide - Libvirt application development guide Component: libvirt-glib - Libvirt GLib, GConfig & GObject libraries Component: libvirt-cim - Libvirt CIM provider Component: libvirt-csharp - Libvirt C# language bindings Component: libvirt-java - Libvirt Java language bindings Component: libvirt-ocaml - Libvirt OCaml language bindings Component: libvirt-perl - Libvirt Perl language bindings Component: libvirt-php - Libvirt PHP language bindings Component: libvirt-publican - Libvirt Publican documentation templates Component: libvirt-sandbox - Libvirt application sandbox toolkit Component: libvirt-snmp - Libvirt SNMP agent Component: libvirt-tck - Libvirt TCK (Technology Compatibility Kit) Component: libvirt-test-API - Libvirt test API Component: libvirt-virshcmdref - Libvirt virsh command reference Component: ruby-libvirt - Libvirt Ruby language bindings The bug reporting form is here: https://bugzilla.redhat.com/enter_bug.cgi?product=Virtualization%20Tools NB, if you are using a binary package provided by your OS vendor, then you should use their bug tracker for reporting bugs first. Feel free to also report it to the libvirt upstream bug tracker at the same time though. Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|

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[libvirt-users] [libivrt-users] What features of kernel are required to support virDomainGetCPUStats?
by Zhihua Che 28 May '12

28 May '12

Hi, Weeks ago, I developed my app under ubuntu-11.10 (kernel 3.0) with lilbvirt-0.9.10. In my code , I used virDomainGetCPUStats to query cpu usage info of domains, and it worked well. However, today, I port my code to ubuntu-10.04.4 (kernel 2.6.32) with libvirt-0.9.10, I find the function virDomainGetCPUStats can't work and complains "this function is not supported by the connection driver: virDomainGetCPUStats". I guess the kernel difference causes this problem because the libvirt is the same on two operating systems. I wonder what features of kernel are required to support virDomainGetCPUStats? I thought cgroup is a prerequisite. The following are .config files of two kernels. ubuntu-11.10 CONFIG_CGROUP_FREEZER=y CONFIG_CGROUP_DEVICE=y CONFIG_CPUSETS=y CONFIG_PROC_PID_CPUSET=y CONFIG_CGROUP_CPUACCT=y CONFIG_RESOURCE_COUNTERS=y CONFIG_CGROUP_MEM_RES_CTLR=y CONFIG_CGROUP_MEM_RES_CTLR_SWAP=y CONFIG_CGROUP_MEM_RES_CTLR_SWAP_ENABLED=y CONFIG_CGROUP_PERF=y CONFIG_CGROUP_SCHED=y CONFIG_FAIR_GROUP_SCHED=y CONFIG_RT_GROUP_SCHED=y CONFIG_BLK_CGROUP=y ubuntu-10.04.4 CONFIG_CGROUP_NS=y CONFIG_CGROUP_FREEZER=y CONFIG_CGROUP_DEVICE=y CONFIG_CPUSETS=y CONFIG_PROC_PID_CPUSET=y CONFIG_CGROUP_CPUACCT=y CONFIG_RESOURCE_COUNTERS=y CONFIG_CGROUP_MEM_RES_CTLR=y CONFIG_CGROUP_MEM_RES_CTLR_SWAP=y CONFIG_CGROUP_SCHED=y CONFIG_FAIR_GROUP_SCHED=y CONFIG_RT_GROUP_SCHED=y CONFIG_MM_OWNER=y As you can see, CPUSET and CPUACCT are enabled in both kernels. So what else features of kernel are required to support virDomainGetCPUStats? harvey

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[libvirt-users] Cannot connect to the existing LXC containers (console)
by Sebastien Douche 28 May '12

28 May '12

Hi, after 2 years of "pure" LXC usage, I'm trying now to administrate our LXC containers with libvirt No problem with a LXC container I create "from Scratch" (lxc-create), but with our existing containers, I've a strange behavior with the console: vsonde43 login: Debian GNU/Linux 5.0 vsonde43 console vsonde43 login: Debian GNU/Linux 5.0 vsonde43 tty1 vsonde43 login: Debian GNU/Linux 5.0 vsonde43 console vsonde43 login: Debian GNU/Linux 5.0 vsonde43 tty1 vsonde43 login: Debian GNU/Linux 5.0 vsonde43 console vsonde43 login: root Password: z Login incorrect vsonde43 login: Login incorrect vsonde43 login: root Password: Password: Login incorrect vsonde43 login: root INIT: Id "c2" respawning too fast: disabled for 5 minutes INIT: Id "c3" respawning too fast: disabled for 5 minutes INIT: Id "c4" respawning too fast: disabled for 5 minutes INIT: Id "c2" respawning too fast: disabled for 5 minutes INIT: Id "c3" respawning too fast: disabled for 5 minutes INIT: Id "c4" respawning too fast: disabled for 5 minutes Characters sometimes appears, and sometimes all keys are like the enter key. Any ideas? I tried many xml configurations w/o sucsess. Thanks. PS: libvirt 0.9.8 / lxc 0.7.5 -- Sebastien Douche <sdouche(a)gmail.com> Twitter: @sdouche / G+: +sdouche

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[libvirt-users] Spawn new domains from a snapshot.
by NoxDaFox 27 May '12

27 May '12

Hello everybody, I would like to be able to spawn several domains from a given snapshot. Here's a possible scenario: - I start from disk image A.qcow2. - I made some changes to A and I take different snapshots: 1 - 2 - 3 - While A is still running I would like to run domains B and C from snapshot 2 I don't want to revert a domain, I want to create new ones. The original should be still running but it may be stopped if necessary. The idea I had was to create a qcow2 image through qemu-img (let's call it Z.qcow2), as I'm using copy on write for performances then I'd need to commit the changes contained in Z to A always using qemu-img. Is there any other better way? I would love to do it through libvirt, maybe specifying in the config file the backing store path of the whole disk and then giving as a source file the one containing deltas. This could be a good idea for realizing a cloud based system as a incredible amount of time would be saved though it. Imagine moving only qcow2 file containing deltas through the network and then give the base image to each node so that it can use it for start it's own domain. As well would be possible to store the heavy base image in a single node saving storage space. Lots of cpu cycles saved once new image versions must be deployed (typical case a windows update to propagate in the nodes network). NoxDaFox

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[libvirt-users] How to specify the libvirtd in connect call
by Zhihua Che 25 May '12

25 May '12

Hi, Here is my situation, I install libvirt in a non-default directory and start libvird with sudo. While I can connect virsh to libvirtd using "virsh --connect qemu:///system", I fail to connect my app using "virConnectOpen("qemu:///system")", which complains "unable to locate libvirtd daemon in $PATH". Then, I take another try and add the path of libvirtd in env variable PATH. Unfortunately, it doesn't work. I read through the api reference and find no place to specify this path explicitly. Thanks for any tip. Harvey

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[libvirt-users] monitor socket did not show up.: No such file or directory
by vipul borikar 23 May '12

23 May '12

I am using a Nimbus Cloud Middleware which in turn use Python libvirt binding to start VM's. Hypervisor is KVM. # virsh -c qemu:///system version Compiled against library: libvir 0.8.7 Using library: libvir 0.8.7 Using API: QEMU 0.8.7 Running hypervisor: QEMU 0.12.1 Some time i get the error in the Nimbus Logs it says : UnexpectedError: Problem creating the VM: monitor socket did not show up.: No such file or directory I googled but this particular not able to find. I checked the /var/log/libvirt/qemu/wrksp-427.log 2012-05-23 10:09:13.494: starting up LC_ALL=C PATH=/sbin:/usr/sbin:/bin:/usr/bin HOME=/root USER=root LOGNAME=root QEMU_AUDIO_DRV=none /usr/libexec/qemu-kvm -S -M rhel6.1.0 -enable-kvm -m 2024 -smp 2,sockets=2,cores=1,threads=1 -name wrksp-427 -uuid e8c5c171-392c-02e4-b43c-b0b4279e55c5 -nodefconfig -nodefaults -chardev socket,id=charmonitor,path=/var/lib/libvirt/qemu/wrksp-427.monitor,server,nowait -mon chardev=charmonitor,id=monitor,mode=control -rtc base=utc -boot c -drive file=/VM/Nimbus/secureimages/wrksp-427/ param-vm.cdacb.in/cloud/5f4f0dcd//RHEL5.5_64bit_MPI,if=none,id=drive-ide0-0-0,format=raw-device ide-drive,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 -netdev tap,fd=24,id=hostnet0 -device rtl8139,netdev=hostnet0,id=net0,mac=a2:aa:bb:2e:d6:58,bus=pci.0,addr=0x3 -usb -vnc 127.0.0.1:22 -vga cirrus -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x4 10:09:13.512: 14116: info : libvirt version: 0.8.7, package: 18.el6 (Red Hat, Inc. <http://bugzilla.redhat.com/bugzilla>, 2011-04-18-10:28:30, x86-008.build.bos.redhat.com) 10:09:13.512: 14116: debug : virCgroupNew:566 : New group /libvirt/qemu/wrksp-427 10:09:13.513: 14116: debug : virCgroupDetect:245 : Detected mount/mapping 0:cpu at /cgroup/cpu in 10:09:13.513: 14116: debug : virCgroupDetect:245 : Detected mount/mapping 1:cpuacct at /cgroup/cpuacct in 10:09:13.513: 14116: debug : virCgroupDetect:245 : Detected mount/mapping 2:cpuset at /cgroup/cpuset in 10:09:13.513: 14116: debug : virCgroupDetect:245 : Detected mount/mapping 3:memory at /cgroup/memory in 10:09:13.513: 14116: debug : virCgroupDetect:245 : Detected mount/mapping 4:devices at /cgroup/devices in 10:09:13.513: 14116: debug : virCgroupDetect:245 : Detected mount/mapping 5:freezer at /cgroup/freezer in 10:09:13.513: 14116: debug : virCgroupDetect:245 : Detected mount/mapping 6:blkio at /cgroup/blkio in 10:09:13.513: 14116: debug : virCgroupMakeGroup:497 : Make group /libvirt/qemu/wrksp-427 10:09:13.513: 14116: debug : virCgroupMakeGroup:509 : Make controller /cgroup/cpu/libvirt/qemu/wrksp-427/ 10:09:13.513: 14116: debug : virCgroupMakeGroup:509 : Make controller /cgroup/cpuacct/libvirt/qemu/wrksp-427/ 10:09:13.514: 14116: debug : virCgroupMakeGroup:509 : Make controller /cgroup/cpuset/libvirt/qemu/wrksp-427/ 10:09:13.514: 14116: debug : virCgroupMakeGroup:509 : Make controller /cgroup/memory/libvirt/qemu/wrksp-427/ 10:09:13.514: 14116: debug : virCgroupSetValueStr:290 : Set value '/cgroup/cpu/libvirt/qemu/wrksp-427/tasks' to '14116' 10:09:13.714: 14116: debug : virCgroupSetValueStr:290 : Set value '/cgroup/cpuacct/libvirt/qemu/wrksp-427/tasks' to '14116' 10:09:14.467: 14116: debug : virCgroupSetValueStr:290 : Set value '/cgroup/cpuset/libvirt/qemu/wrksp-427/tasks' to '14116' 10:09:15.467: 14116: debug : virCgroupSetValueStr:290 : Set value '/cgroup/memory/libvirt/qemu/wrksp-427/tasks' to '14116' 2012-05-23 10:09:16.537: shutting down There is no suspect in the log file. Any Ideas??? -- Thanks Vipul Borikar "Our task must be to free ourselves...by widening our circle of compassion to embrace all living creatures and the whole of nature and its beauty."

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Re: [libvirt-users] Snapshot system: really confusing.
by NoxDaFox 23 May '12

23 May '12

Hello, thank you for your fast reply! To help in comprehension I'll explain you a bit what am I trying to realize so the picture will be more clear. Basically it's a platform for debug, what I need is to access to the memory dump image and to the FS ones; I don't need any reverting support. The common lifecycle of a domain is: a) Given a backing store disk (qcow2) I create a new disk image: my_image.qcow2 b) I start this image and play around based on a persistent domain. c) I take several pictures (snapshots, dumps) of the VE state: I need at least readable pictures of the FileSystem and the RAM. d) I shutdown the guest. e) I extract valuable information from the pictures. This is the critical phase where all my doubts on libvirt platform come from. f) I store those information. g) I wipe out everything else. h) Ready for a new test, return to point a). libvirt is a great platform! And documentation is not bad at all. The only nebulous part is the snapshot part (I guessed was on hard development anyway). Now I'll answer to your points. > > Greetings, > > Hello, > > > > > I am developing a platform for test and debug use. > > > > The typical scenario I want to realize is the following: > > > > I run a .qcow2 image via QEMU-KVM, the running OS is not relevant. > > I want to take several snapshots of both Disk and RAM status; same file, > > separate files doesn't matter. > > I just need a way to have consistent information about them (better with > > XML description) and the data as well. > > I want to store these snapshots on my storage devices to use them whenever > > and wherever I want. > > Hopefully libvirt can supply what you are interested in; and be aware > that it is a work in progress (that is, unreleased qemu 1.1 and libvirt > 0.9.12 will be adding yet more features to the picture, in the form of > live block copy). I knew the situation, I saw a RFC of yours that is really interesting as it introduces snapshots of single storage volumes: virStorageVolSnapshotPtr. Really interesting under my point of view. > > > > > > Is it possible to store a single snapshot providing both the memory and > > disks state in a file (maybe a .qcow2 file)? > > Single file: no. Single snapshot: yes. The virDomainSnapshotCreateXML > API (exposed by virsh snapshot-create[-as]) is able to create a single > XML representation that libvirt uses to track the multiple files that > make up a snapshot including both memory and disk state. This would be enough, as long as I'm able to read those information. > > > Is there any way to get a unique interface which handles my snapshots? > > > > I was used to use the virDomainSnapshotCreateXML() defining the destination > > file in the XML with <disk> fields. > > Right now, you have a choice: > > 1. Don't use the DISK_ONLY flag. That means that you can't use <disk> > in the snapshot XML. The snapshot then requires qcow2 files, the VM > state is saved (it happens to be in the first qcow2 disk), and the disk > state is saved via qcow2 internal snapshots. That's good to know, I just got yesterday, reading your mails in the dev mailing list, where snapshots were stored; I always tried to look for a new file, unsuccessfully. > > 2. Use the DISK_ONLY flag. Then you can set up external snapshot file > names (basically, another layer of qcow2 files, where your original file > name is now the snapshot backing the new layer), and you get no VM state > directly. Here is where the <disk> element of the snapshot comes into > play. If you _also_ want to save VM state, you can use 'virsh save' > (virDomainSaveFlags) to save just VM state; but then you have to > coordinate things so that the disk snapshot and the VM state correspond > to the same point in guest time by pausing the guest before taking the > disk snapshot. > > > After updating libvirt it was not working anymore, I thought was a bug but > > then I realized it was intentional. > > The function complains about the fact that the <disk> parameter is not > > accepted anymore. > > What versions of libvirt are you playing with? <disk> was unrecognized > (and ignored) prior to 0.9.5; after that point, it can only be used with > the DISK_ONLY flag, but then you have to take the VM state separately. > I guessed that the <disk> tag was just ignored, I inherited the code from a previous project and I spent the first weeks struggling with what was not working. I was using libvirt 0.8.3-5 from debian squeeze, I migrated to wheezy to be able to access to libguestfs features, now I'm running libvirt 0.9.11. > Someday, I'd like to submit more patches to allow <disk> to be mixed > with live VM state, but I'm not there yet. > > > So I started guessing how to solve reading the API documentation and I fall > > in a completely nebulous world. > > > > For what I got: > > - virDomainSnapshotCreateXML(): > > According to flags can take system checkpoints (really useful) and disks > > snapshots. > > System checkpoints: What I need but I didn't find any way to retrieve the > > storage file; I'm only able to get the snapshot pointer, quite useless as > > from its pointer I can only print the XML description. > > The storage is in internal snapshots of your qcow2 file. Try 'qemu-img > info /path/to/file' to see those internal snapshots. You can also use > > qemu-img convert -s snapname /path/to/image /path/to/output Great! This is the information I needed: how to access to those damned snapshot in a readable way. I still believe anyway that an interface provided by libvirt would be really valuable. I am trying to stay as much as I can on libvirt to work on a higher level of abstraction, this is really important for my architecture. Using directly qemu is quite annoying but if at the moment is the only solution I'll move to that. > > as a way to extract that snapshot into a file that you can use > independently (but only while your guest is not running); alas, qemu > doesn't yet provide a way to extract this information from a running > domain, nor have I yet had time to map this functionality into libvirt > API. But I have requested qemu enhancements to allow it (perhaps by > qemu 1.2), as well as have a vision of where I plan to take the libvirt > API in the next year or so to make this more useful. ATM I don't need "on the fly" extraction, everything is done after turning off the guest, what I need is a way to get its state whenever I want, reading it is another business. But indeed this is something that in a future may be greatly valuable. > > > Disk snapshot: here through the XML description I can specify a target file > > where to write the information. But I still need the memory status. > > - virDomainSaveFlags(): > > No matter how I set the flags, it halts the guest; I need it still running > > afterward and I think that reverting the domain and restarting for my > > scenarios is unaffordable. > > Yeah, that's another thing on my list, to add a flag to > virDomainSaveFlags that will keep the domain running after the save is > complete, and/or enhance virDomainSnapshotCreateXML to incorporate a > domain save to an external file alongside disk snapshots at the same > point in guest time. I'd also like to play with background migration > (right now, virDomainSaveFlags does a foreground migrate-to-file, which > pauses the guest up front; but a minimal downtime solution would use the > live migration path which results in a larger output file but much less > downtime). > > > - virDomainCoreDump(): > > Does what I need for the memory, but doesn't give any XML description and > > doesn't supply any useful interface to handle it, I just get back an int > > that represent the exit status of the routine. > > virDomainCoreDump() and virDomainSaveFlags() both do a migration to > file, it's just that the core dump version isn't designed for reverting > like domain save. And there have been proposals on list for making core > dump management better (such as allowing you to get at a core dump file > from a remote machine; right now, the core dump can only be stored on > the same machine as the guest being dumped). > I think this is bad, why not merging these functions? Under an API point of view (I'm aware of architectural difficulties on the background) this is useless and confusing. Better a virDomainSaveFlags() with several configuration than two different functions. This is a complex system-management API, so anyone who'll use it will be conscious of that; I don't think that many flags and XML files will be confusing as long as they're clearly documented. But having multiple interfaces (alias functions/methods) that basically do the same in a different way with slightly different results is really confusing. Better have a single method configurable with XML files and flags than two without. (This is a point of view of mine as a developer). > > (other functions really similar) > > > > The question is: why all this confusion? > > Different qemu capabilities ('savevm', 'migrate', > 'blockdev-snapshot-sync'), different needs at the time each feature was > first added, etc. Ultimately, virDomainSnapshotCreateXML is the most > powerful interface, and I have plans to make it be a superset of > virDomainSaveFlags(), but I'm not there yet. Indeed is a powerful interface! But again: why those functions do something similar? Isn't better (always under an API point of view) having: - Two different interfaces that handle separately disk and state; if I want to revert/migrate I need to give both the results of those interfaces. - One interface that gives revert/migrate capability and one interface that, via flags or XML, gives the separate components. - Other combinations: may still be done as long as they're clear. Here we have: virDomainSnapshotCreateXML(): Takes complete snapshots, disk snapshots, no single-memory snapshots. It does it keeping the domain alive (paused). It stores information internally if flags=A, externally if flags=B. virDomainSaveFlags(): No complete snapshots, no disk snapshots, takes memory snapshots. It does it stopping the domain. It stores information externally. Under my point of view this can be done in a more clear way. Separation of duties: many small functions that do a single thing and a global one that wraps everything giving a complete package is a good example. > > > I absolutely understand the problematic that realizing a multiplatform > > snapshots management raises; but I think that for an API purpose what is > > implemented here is completely confusing the developer. > > Is there anything I can do to help improve the documentation? I know > that's an area where a picture can speak a thousand words; and as more > features get added into the snapshot picture, it probably becomes more > important to accurately display the various APIs and the advantages for > using each. What's basically missing is data flow and representation, you don't need to realize it by scratch (data format is strongly bound to qemu) but give an idea and provide references. What makes a documentation relevant is the way the reader has to access to information, must be easy! If snapshots reliy to qemu ones just link their documentation as well, so if I don't find enough clues I can go deeper as much as needed. If help is needed I can contribute, I just need to know where to look at when I need something. The platforms I'm working on are really time-consuming but this technology is really important under my point of view as it will reduce the time to maintain them. Thanks again for answering so fast! NoxDaFox PS: I forgot to CC the libvirt-users mailing list, sorry for the spam.

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[libvirt-users] Renaming a LVM LV (where is vol-edit??)
by Dax Kelson 23 May '12

23 May '12

Hello, I'm using a LVM storage pool. I renamed a guest and I would like to change the LV name to match to avoid future confusion. How do i do this? There is no vol-edit command (fully updated RHEL6). Thanks, Dax Kelson

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[libvirt-users] Failed to mount devpts
by Marco Yuen 22 May '12

22 May '12

Hi all, I've been trying to start a LXC container using libvirt, but I keep getting `Failed to mount devpts on /vservers/quantum/fs/dev/pts: Invalid argument'. I found a similar thread on the mailing list a couple months ago (https://www.redhat.com/archives/libvirt-users/2012-January/msg00052.html) but the solution posted didn't work for me. Anyone has any ideas? Extra Info: Libvirt version Compiled against library: libvir 0.9.12 Using library: libvir 0.9.12 Using API: LXC 0.9.12 Running hypervisor: LXC 3.3.5 Host is running F16, and the domain xml can found at http://pastebin.com/yWXQviVy Best regards, Marco

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Re: [libvirt-users] Python Libvirt Bindings
by Hubert Zhang 22 May '12

22 May '12

https://www.redhat.com/archives/libvirt-users/2012-May/msg00005.html When I run the sample code with the case of Python code for using qemu+tcp with SASL, I always got this SASL error: Traceback (most recent call last): File "esxList.py", line 102, in ? conn = libvirt.openAuth(uri, auth, 0) File "/usr/lib/python2.4/site-packages/libvirt.py", line 102, in openAuth if ret is None:raise libvirtError('virConnectOpenAuth() failed') libvirt.libvirtError: authentication failed: Failed to start SASL negotiation: -4 (SASL(-4): no mechanism available: I have no problem to run the C&java code with qemu+tcp with SASL. Is it possible an error of Python binding? Thanks, -Hubert

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[libvirt-users] Problem with pty
by Daniele Milani 21 May '12

21 May '12

Dear all I have the following problem: -I'm running libvirt 0.9.11 on ubuntu 12.04; -when I try to create a VM with the following configuration: ... <serial type='pty'> <source path='/dev/pts/2'/> <target port='0'/> <alias name='serial0'/> </serial> <console type='pty' tty='/dev/pts/2'> <source path='/dev/pts/2'/> <target type='serial' port='0'/> <alias name='serial0'/> </console> ... I obtain this output: errore: Impossibile creare il dominio da domain_alpha_1.xml (error, impossible to create a domain from domain_alpha_1.xml) errore: errore interno Process exited while reading console log output: chardev: opening backend "pty" failed: Permission denied Does anyone know what's going wrong and ho to fix it? Thanks, Daniele Milani

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[libvirt-users] F14->F16 Upgrade Results in Win2003 Server Client BSOD 0x7f
by Thomas J. Baker 21 May '12

21 May '12

Hello, I upgraded my kvm server from Fedora 14 to Fedora 16 and the only casualty was a Windows 2003 Server client that will no longer boot with and produces a BSOD. I admittedly know very little about Windows and this VM has been around - real hardware -> Parallels on a Mac -> linux kvm but it was working fine under Fedora 14. The client does boot fine under safe mode but anything higher than that (even safe mode with networking) results in the BSOD. I've tried explicitly setting the network driver to rtl8139 in virt-manager which appears to be what it was under F14 but it didn't help. Neither did just removing the NIC under Device Manager and letting it get recognized again. As you can guess given the description, this crusty old Win2003 server instance has some worth in that recreating it is very undesirable for all involved. I'd appreciate any tips on getting it working again. Thanks, tjb -- ======================================================================= | Thomas Baker email: tjb(a)unh.edu | | Systems Programmer | | Research Computing Center voice: (603) 862-4490 | | University of New Hampshire fax: (603) 862-1761 | | 332 Morse Hall | | Durham, NH 03824 USA http://wintermute.sr.unh.edu/~tjb | =======================================================================

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