- Users - libvirt List Archives

[libvirt-users] snapshots and qcow2
by Laszlo Hornyak 09 Dec '14

09 Dec '14

Hi, I ran into a strange behavior with libvirt snapshots. I have some vms running with thin-provisioned qcow2 disk images (libvirt 1.1.3 with fedora 20). * When I create a snapshot on the VM, the qcow file suddenly grows big, somewhat bigger than the maximum size of the disk. * When I delete the snapshot, the allocated disk space is not freed up, the qcow image remains the same size. However, if I create a new snapshot again, it will take the previous snapshot's space. This does not seem to be very well documented in qemu and the man page, manual, online documentation, wiki etc does not mention it. Is there a way to free up the space allocated for snapshots? Thank you, Laszlo -- EOF

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[libvirt-users] all.accept_redirects force disabled with libvirt
by Thomas Lau 09 Dec '14

09 Dec '14

Hi All, I was having trouble to enable all.accept_redirects due to our network structure, we have to enable it, but all libvirt installed machines contain this setting: net.ipv4.conf.all.accept_redirects = 0 I even use sysctl.conf to force to enable it, still no go, anyone know why? -- Thomas Lau Director of Infrastructure Tetrion Capital Limited Direct: +852-3976-8903 Mobile: +852-9323-9670 Address: 20/F, IFC 1, Central district, Hong Kong

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[libvirt-users] libgfapi disk locking in virtlockd not working
by Piotr Rybicki 08 Dec '14

08 Dec '14

Hello. I'm playing with libgfapi network disks, over IB and all is working fine, but not disk locking (and true rdma transport). I use virtlockd, and with fuse mount, locking works as expected. But when i converted disk definitions to libgfapi, locks are not created (but qemu starts and works fine). I used direct and indirect locking - same result : qemu working fine, no locks. my revelant xml section: <disk type='network' device='disk'> <driver name='qemu' type='raw' cache='writethrough' iothread='1'/> <source protocol='gluster' name='pool_test/gentoo-virtio-lib1-sys.img'> <host name='X.X.X.X' port='24007' transport='rdma'/> </source> <target dev='vda' bus='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> </disk> I also tried devices <lease> but it also doesn't work: <lease> <lockspace>somearea</lockspace> <key>somekey</key> <target path='/data/nfs/lockd'/> </lease> # virsh start gentoo-virtio-lib1 błąd: Uruchomienie domeny gentoo-virtio-lib1 nie powiodło się błąd: internal error: Lockspace for path /data/nfs/lockd/somearea does not exist well, lockspace exists... # ls -al /data/nfs/lockd razem 4K drwxrwxrwx 3 root root 21 12-08 22:43 . drwxrwxrwt 7 root root 4096 12-08 14:29 .. drwxrwxrwx 2 qemu qemu 6 12-08 22:43 somearea # ls -al /data/nfs/lockd/somearea/ razem 0K drwxrwxrwx 2 qemu qemu 6 12-08 22:43 . drwxrwxrwx 3 root root 21 12-08 22:43 .. Are libgfapi based disks supported by virtlockd? Is there a bug. Am I missing something? My test system: # uname -r 3.14.24-gentoo # libvirtd -V libvirtd (libvirt) 1.2.10 # virtlockd -V virtlockd (libvirt) 1.2.10 # qemu-x86_64 -version qemu-x86_64 version 2.1.2, Copyright (c) 2003-2008 Fabrice Bellard # glusterfs -V glusterfs 3.5.20141204.7b160e3 built on Dec 8 2014 19:03:37 (normally 3.5.2, but was curious if 3.5 series nightly buld will enable true RDMA transfer, not IPOIB. - it did not). Best regards Piotr Rybicki

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[libvirt-users] command reference
by Laszlo Hornyak 08 Dec '14

08 Dec '14

Hi, I have found the online command reference somewhat incomplete so I thought I give it a try and fill in some of the gaps, but when I cloned the repo I noticed that the last commit happened a little more than 3 years ago. Do you guys accept patches for the documentation? What is the plan in general for the future on the documentation front lines? -- EOF

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[libvirt-users] best shared storage solution ?
by Jason Vas Dias 08 Dec '14

08 Dec '14

Good day - Is there a way of safely allowing a guest OS to access a disk storage device that is also mounted at the same time by the hypervisor or another guest ? I have Linux LVM volumes containing ext4 and btrfs filestystems that need to be shared between the hypervisor and the guests, and between guests . Attempts to use NFS are too slow to be useable - it takes a guest around 4 hours to uncompress and extract a 10MB tar file (using 4 2.9GHz cores). I need access to the shared file system at all times to use as my /home directory from the hypervisor host, so I guess this rules out iSCSI . I came accross documentation on 'sanlock', but its purpose seems to be antithetical to what I require, as described at: http://libvirt.org/locking.html : " how to ensure a single disk cannot be used by more than one running VM at a time, across any host in a network" - but I want to ensure SAFE concurrent access by multiple VMs or any kernel , either on the hypervisor hardware or in a VM guest, to the same filesystems ( ext4, btrfs ) on the same machine, without having to use a network file system . Can sanlock be used to accomplish this ? Or is there any other method that allows the same filesystem to be safely accessed by more than one kernel running on the same host ? The libvirt documentation is very sketchy on this subject, but I understand that just using the '<shareable/>' in the VM configuration XML is not enough, and a lock manager must be configured - can sanlock be used for this, or is there another lock manager that can ? Thanks & Regards, Jason Vas Dias

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[libvirt-users] Libvirt Live Migration
by Dhia Abbassi 04 Dec '14

04 Dec '14

I'm trying to implement a virtualization API. I was testing migration with libvirt I got some problems. When I use the following command : *virsh migrate --live --persistent --copy-storage-all vm-clone1 qemu+ssh://server_ip/system* the migration works fine but in the destination host the migrated vm is paused and I can't unpause it and I need to reboot the vm to be able use it in the new host. When I try to unoause it Igot the following error message: << *Error unpausing domain: internal error: unable to execute QEMU command 'cont': Resetting the Virtual Machine is required *>> How can I solve this problem, or is there an other way to make a live migration with libvirt?? Thank you for you consideration. -- Best regards *Dhia Abbassi* Full Stack Engineer | Rosafi Holding <http://tn.linkedin.com/in/dhiaabbassi> <https://github.com/DhiaTN> <https://plus.google.com/u/0/+DhiaAbbassi> <https://twitter.com/DhiaTN>

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[libvirt-users] Problem with /dev/tty in LXC established with virt-install
by Vegard Vesterheim 04 Dec '14

04 Dec '14

I have created a LXC container with debootstrap followed by virt-install like this: host=mylxc1 debootstrap wheezy /home/lxc/$host virt-install -c lxc:// -n $host --filesystem /home/lxc/$host,/ --ram 1024 I am confused about the /dev filesystem in this container. Specifically the device '/dev/tty'. >From inside the container: ~# ls -la /dev/tty ls: cannot access /dev/tty: No such file or directory # mknod -m 666 /dev/tty c 4 0 mknod: `/dev/tty': Operation not permitted A LXC container created and started with the native LXC commands (lxc-create/lxc-start) has a functioning /dev/tty: # cat </dev/tty foo foo ^C How can I create a functioning /dev/tty with the LXC driver in libvirt? - Vegard V -

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[libvirt-users] Libvirt building fails after download from git
by Pavel Khrulev 03 Dec '14

03 Dec '14

Hello. I need to build libvirt-1.2.10 (with mingw fix) in mingw in windows. I did autogen in linux mint 16, then transferred all files from libvirt directory (sources, configure, makefile.in, ... ) to windows xp. Libvirt is successfully builded in mingw in winxp. Ok. I uploaded all libvirt files (that were successfully builded) to git repository from linux. Then I cloning git rep to windows. And when I do configure, then config.h is not the same with config.h, which is created earlier (before git). And due to this config.h, building libvirt is failed. All files (before upload and arter download ) are the same (checked by KDiff). Do you know, what a problem? May be the problem is in timestamps. (But I tried to touch all files) Or some reconfigure after git. I really dont know. Pavel Khrulev

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[libvirt-users] serial connection between two guests
by Jd 01 Dec '14

01 Dec '14

Hi Is it possible to drive a serial connection between two guests ? For example, the virt-io serial channel used by guestfsd. Can it be driven by virt-io serial connection from another VM ? How do you attach the same device on host as server in one VM and client as another ? Any details on how to go about doing this ? Thanks /Jd

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[libvirt-users] python migrateSetMaxSpeed not taking effect
by Krutskikh Ivan 28 Nov '14

28 Nov '14

Hi, I am writing a simple python script for migrating vm's based on zfs zvol's. Either I am doing something wrong or python migrateSetMaxSpeed not taking effect: no mater what value I specify (except for 0), I end up with 10 Mib/s migration speed. The code is: def virt_migrate(domain): conn = libvirt.open('qemu:///system') domain_obj = conn.lookupByName(domain) dst='qemu+ssh://root@%s/system' % args.remote domain_obj.migrateSetMaxSpeed(40,0) new_dom = domain_obj.migrateToURI(dst,libvirt.VIR_MIGRATE_LIVE | libvirt.VIR_MIGRATE_PEER2PEER | libvirt.VIR_MIGRATE_NON_SHARED_INC | libvirt.VIR_MIGRATE_PERSIST_DEST | libvirt.VIR_MIGRATE_UNDEFINE_SOURCE, None, 0) conn.close() Also tried to specify bandwidth at migrateToUri- I still get 10 mib/s at any value... Thanks in advance!

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