- Users - libvirt List Archives

Live migration with change to setmaxmem
by Dariusz Smigiel 07 Apr '21

07 Apr '21

Hi Team, I need to migrate beefy instance between two different hosts which is running out of resources. I was wondering, if there is a way to change maximum memory value during live migration, without shutting down the instance. Thanks, Dariusz

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Re: Regarding location of Libvirt library
by Andrea Bolognani 06 Apr '21

06 Apr '21

[please keep replies on-list] On Mon, 2021-04-05 at 12:03 +0530, shafnamol N wrote: > Hi, > I have build libvirt in the following method: > $ meson build -Dsystem=true > $ ninja -C build > When i tried to get the information via > > $pkg-config --cflags --libs libvirt > > it doesnt show anything. > > But I tried > $ninja -C build install > > and then > $pkg-config --cflags --libs libvirt > It shows like: > libvirt-7.1.0]# pkg-config --cflags --libs libvirt > -lvirt This is expected: pkg-config can't find the libvirt.pc file until you've installed it :) > But the problem is when i tried to get the status of libvirt > > # systemctl status libvirtd > ● libvirtd.service > Loaded: not-found (Reason: Unit libvirtd.service not found.) > Active: failed (Result: exit-code) > > I tried with > # systemctl daemon-reload > But the problem persists.. > what will be the problem... What does running $ ls /usr/lib/systemd/system/*virt* output? What does the Miscellaneous ... Init script: XXX entry look like in the summary that's displayed when you run Meson? What OS are you using? -- Andrea Bolognani / Red Hat / Virtualization

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Virtual Network API for QEMU
by Radek Simko 03 Apr '21

03 Apr '21

Hi, According to this support matrix https://libvirt.org/hvsupport.html#virNetworkDriver there is no support for any APIs other than hypervisor ones for qemu. For example virConnectNumOfNetworks is not supported. Is there any particular reason this is not supported? Has any development in that area been attempted in the past? Would contributions adding support be welcomed? Thanks, Radek Simko

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GlusterFS libgfapi with TLS
by lejeczek 01 Apr '21

01 Apr '21

Hi guys. I have KVM guests stored on glusterFS volume and I recently added TLS encryption to Gluster. What changes, tweaks are required at libvirtd/qemu's end? many thanks, L.

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Regarding location of Libvirt library
by shafnamol N 31 Mar '21

31 Mar '21

Hi, I have installed Libvirt 7.1.0. I configured and built libvirt based on instructions from https://libvirt.org/compiling.html. Now I developed a client program to create a VM using an XML file.As the API for it is *virDomainCreateXML,* called this API by passing XML file .It shows the following error. undefined reference to `virDomainCreateXML'. I included the header files containing the said API declaration.But need to include the library also. My question is where do the libvirt library located after building it. Thanks for the help in advance.

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virsh dommemstat doesn't update its information
by Lentes, Bernd 29 Mar '21

29 Mar '21

Hi, i'm playing a bit around with my domains and the balloon driver. To get information about ballooning i use virsh dommemstat. But i only get very few information: virsh # dommemstat vm_idcc_devel actual 1044480 last_update 0 rss 1030144 Also configuring "dommemstat --domain vm_idcc_devel --period 5 --live" or "dommemstat --domain vm_idcc_devel --period 5 --current" does neither update nor extend the information. In vm_idcc_devel virtio_balloon is loaded: idcc-devel:~ # lsmod|grep balloon virtio_balloon 22788 0 Guest OS is SLES 10 SP4. Is that too old ? Host OS is SLES 12 SP5. There are other domains in which the information is updated. Here is the config from vm_idcc_devel: virsh # dumpxml vm_idcc_devel <domain type='kvm' id='7'> <name>vm_idcc_devel</name> <uuid>4993009b-42ff-45d9-b1e0-145b8c0c8f82</uuid> <memory unit='KiB'>2044928</memory> <currentMemory unit='KiB'>1044480</currentMemory> <vcpu placement='static'>1</vcpu> <resource> <partition>/machine</partition> </resource> <os> <type arch='x86_64' machine='pc-i440fx-1.4'>hvm</type> <boot dev='hd'/> <boot dev='cdrom'/> <bootmenu enable='yes'/> </os> <features> <acpi/> <apic/> </features> <clock offset='localtime'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>destroy</on_crash> <devices> <emulator>/usr/bin/qemu-kvm</emulator> <disk type='file' device='disk'> <driver name='qemu' type='raw' cache='none'/> <source file='/mnt/ocfs2/vm_idcc_devel.raw'/> <backingStore/> <target dev='vdb' bus='ide'/> <alias name='ide0-0-0'/> <address type='drive' controller='0' bus='0' target='0' unit='0'/> </disk> <disk type='file' device='cdrom'> <driver name='qemu'/> <target dev='hdc' bus='ide'/> <readonly/> <alias name='ide0-1-0'/> <address type='drive' controller='0' bus='1' target='0' unit='0'/> </disk> <controller type='usb' index='0' model='piix3-uhci'> <alias name='usb'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/> </controller> <controller type='pci' index='0' model='pci-root'> <alias name='pci.0'/> </controller> <controller type='ide' index='0'> <alias name='ide'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> </controller> <interface type='bridge'> <mac address='52:54:00:37:92:05'/> <source bridge='br0'/> <target dev='vnet6'/> <model type='rtl8139'/> <alias name='net0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> <serial type='pty'> <source path='/dev/pts/6'/> <target type='isa-serial' port='0'> <model name='isa-serial'/> </target> <alias name='serial0'/> </serial> <console type='pty' tty='/dev/pts/6'> <source path='/dev/pts/6'/> <target type='serial' port='0'/> <alias name='serial0'/> </console> <input type='mouse' bus='ps2'> <alias name='input0'/> </input> <input type='keyboard' bus='ps2'> <alias name='input1'/> </input> <graphics type='vnc' port='5902' autoport='no' listen='127.0.0.1'> <listen type='address' address='127.0.0.1'/> </graphics> <video> <model type='cirrus' vram='16384' heads='1' primary='yes'/> <alias name='video0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/> </video> <memballoon model='virtio'> <stats period='5'/> <alias name='balloon0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> </memballoon> </devices> </domain> Bernd -- Bernd Lentes System Administrator Institute for Metabolism and Cell Death (MCD) Building 25 - office 122 HelmholtzZentrum München bernd.lentes(a)helmholtz-muenchen.de phone: +49 89 3187 1241 phone: +49 89 3187 3827 fax: +49 89 3187 2294 http://www.helmholtz-muenchen.de/mcd Public key: 30 82 01 0a 02 82 01 01 00 b3 72 3e ce 2c 0a 6f 58 49 2c 92 23 c7 b9 c1 ff 6c 3a 53 be f7 9e e9 24 b7 49 fa 3c e8 de 28 85 2c d3 ed f7 70 03 3f 4d 82 fc cc 96 4f 18 27 1f df 25 b3 13 00 db 4b 1d ec 7f 1b cf f9 cd e8 5b 1f 11 b3 a7 48 f8 c8 37 ed 41 ff 18 9f d7 83 51 a9 bd 86 c2 32 b3 d6 2d 77 ff 32 83 92 67 9e ae ae 9c 99 ce 42 27 6f bf d8 c2 a1 54 fd 2b 6b 12 65 0e 8a 79 56 be 53 89 70 51 02 6a eb 76 b8 92 25 2d 88 aa 57 08 42 ef 57 fb fe 00 71 8e 90 ef b2 e3 22 f3 34 4f 7b f1 c4 b1 7c 2f 1d 6f bd c8 a6 a1 1f 25 f3 e4 4b 6a 23 d3 d2 fa 27 ae 97 80 a3 f0 5a c4 50 4a 45 e3 45 4d 82 9f 8b 87 90 d0 f9 92 2d a7 d2 67 53 e6 ae 1e 72 3e e9 e0 c9 d3 1c 23 e0 75 78 4a 45 60 94 f8 e3 03 0b 09 85 08 d0 6c f3 ff ce fa 50 25 d9 da 81 7b 2a dc 9e 28 8b 83 04 b4 0a 9f 37 b8 ac 58 f1 38 43 0e 72 af 02 03 01 00 01

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how to check a virtual disk
by Lentes, Bernd 29 Mar '21

29 Mar '21

Hi, we have a two-node cluster with pacemaker a SAN. The resources are inside virtual domains. The images of the virtual disks reside on the SAN. On one domain i have errors from the hd in my log: 2021-03-24T21:02:28.416504+01:00 geneious kernel: [2159685.909613] JBD2: Detected IO errors while flushing file data on dm-1-8 2021-03-24T21:02:46.505323+01:00 geneious kernel: [2159704.012213] JBD2: Detected IO errors while flushing file data on dm-1-8 2021-03-24T21:02:55.573149+01:00 geneious kernel: [2159713.078560] JBD2: Detected IO errors while flushing file data on dm-1-8 2021-03-24T21:03:23.702946+01:00 geneious kernel: [2159741.202546] JBD2: Detected IO errors while flushing file data on dm-1-8 2021-03-24T21:03:30.289606+01:00 geneious kernel: [2159747.796192] ------------[ cut here ]------------ 2021-03-24T21:03:30.289635+01:00 geneious kernel: [2159747.796207] WARNING: CPU: 0 PID: 457 at ../fs/buffer.c:1108 mark_buffer_dirty+0xe8/0x100 2021-03-24T21:03:30.289637+01:00 geneious kernel: [2159747.796208] Modules linked in: st sr_mod cdrom lp parport_pc ppdev parport xfrm_user xfrm_algo binfmt_misc uinput nf_log_ipv6 xt_comme nt nf_log_ipv4 nf_log_common xt_LOG xt_limit af_packet iscsi_ibft iscsi_boot_sysfs ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 ipt_REJECT xt_pkttype xt_tcpudp iptable_filter ip6table_mangl e nf_conntrack_netbios_ns nf_conntrack_broadcast nf_conntrack_ipv4 nf_defrag_ipv4 ip_tables xt_conntrack nf_conntrack libcrc32c ip6table_filter ip6_tables x_tables joydev virtio_net net_fai lover failover virtio_balloon i2c_piix4 qemu_fw_cfg pcspkr button ext4 crc16 jbd2 mbcache ata_generic hid_generic usbhid ata_piix sd_mod virtio_rng ahci floppy libahci serio_raw ehci_pci bo chs_drm drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops ttm drm uhci_hcd ehci_hcd usbcore virtio_pci 2021-03-24T21:03:30.289637+01:00 geneious kernel: [2159747.796374] drm_panel_orientation_quirks libata dm_mirror dm_region_hash dm_log sg dm_multipath dm_mod scsi_dh_rdac scsi_dh_emc scsi_ dh_alua scsi_mod autofs4 [last unloaded: parport_pc] 2021-03-24T21:03:30.289643+01:00 geneious kernel: [2159747.796400] Supported: Yes 2021-03-24T21:03:30.289644+01:00 geneious kernel: [2159747.796405] CPU: 0 PID: 457 Comm: jbd2/dm-0-8 Not tainted 4.12.14-122.57-default #1 SLE12-SP5 2021-03-24T21:03:30.289644+01:00 geneious kernel: [2159747.796406] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c89-rebuilt.suse.com 04/01/2014 2021-03-24T21:03:30.289645+01:00 geneious kernel: [2159747.796407] task: ffff8ba32766c380 task.stack: ffff99954124c000 2021-03-24T21:03:30.289645+01:00 geneious kernel: [2159747.796409] RIP: 0010:mark_buffer_dirty+0xe8/0x100 2021-03-24T21:03:30.289646+01:00 geneious kernel: [2159747.796409] RSP: 0018:ffff99954124fcf0 EFLAGS: 00010246 2021-03-24T21:03:30.289650+01:00 geneious kernel: [2159747.796413] RAX: 0000000000a20828 RBX: ffff8ba209a58d90 RCX: ffff8ba3292d7958 2021-03-24T21:03:30.289651+01:00 geneious kernel: [2159747.796413] RDX: ffff8ba209a585b0 RSI: ffff8ba24270b690 RDI: ffff8ba3292d7958 2021-03-24T21:03:30.289652+01:00 geneious kernel: [2159747.796414] RBP: ffff8ba3292d7958 R08: ffff8ba209a585b0 R09: 0000000000000001 2021-03-24T21:03:30.289652+01:00 geneious kernel: [2159747.796415] R10: ffff8ba328c1c0b0 R11: ffff8ba287805380 R12: ffff8ba3292d795a 2021-03-24T21:03:30.289653+01:00 geneious kernel: [2159747.796415] R13: 0000000000000000 R14: ffff8ba3292d7958 R15: ffff8ba209a58d90 2021-03-24T21:03:30.289653+01:00 geneious kernel: [2159747.796417] FS: 0000000000000000(0000) GS:ffff8ba333c00000(0000) knlGS:0000000000000000 2021-03-24T21:03:30.289654+01:00 geneious kernel: [2159747.796417] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 2021-03-24T21:03:30.289654+01:00 geneious kernel: [2159747.796418] CR2: 0000000099bff000 CR3: 0000000101b06000 CR4: 00000000000006f0 2021-03-24T21:03:30.289655+01:00 geneious kernel: [2159747.796424] Call Trace: 2021-03-24T21:03:30.289656+01:00 geneious kernel: [2159747.796470] __jbd2_journal_refile_buffer+0xbb/0xe0 [jbd2] 2021-03-24T21:03:30.289656+01:00 geneious kernel: [2159747.796479] jbd2_journal_commit_transaction+0xf1a/0x1870 [jbd2] 2021-03-24T21:03:30.289657+01:00 geneious kernel: [2159747.796489] ? __switch_to_asm+0x41/0x70 2021-03-24T21:03:30.289658+01:00 geneious kernel: [2159747.796490] ? __switch_to_asm+0x35/0x70 2021-03-24T21:03:30.289662+01:00 geneious kernel: [2159747.796493] kjournald2+0xbb/0x230 [jbd2] 2021-03-24T21:03:30.289663+01:00 geneious kernel: [2159747.796499] ? wait_woken+0x80/0x80 2021-03-24T21:03:30.289663+01:00 geneious kernel: [2159747.796503] kthread+0xf6/0x130 2021-03-24T21:03:30.289664+01:00 geneious kernel: [2159747.796508] ? commit_timeout+0x10/0x10 [jbd2] 2021-03-24T21:03:30.289664+01:00 geneious kernel: [2159747.796510] ? kthread_bind+0x10/0x10 2021-03-24T21:03:30.289665+01:00 geneious kernel: [2159747.796511] ret_from_fork+0x35/0x40 2021-03-24T21:03:30.289665+01:00 geneious kernel: [2159747.796517] Code: 1b 48 8b 03 48 8b 7b 08 48 83 c3 18 48 89 ee e8 bf 42 76 00 48 8b 03 48 85 c0 75 e8 e9 3c ff ff ff 48 89 df 5b 5d e9 c8 35 fb ff <0f> 0b e9 26 ff ff ff 48 83 e8 01 e9 5b ff ff ff 0f 1f 84 00 00 2021-03-24T21:03:30.289670+01:00 geneious kernel: [2159747.796533] ---[ end trace db796891c8ff94af ]--- 2021-03-24T21:03:46.593225+01:00 geneious kernel: [2159764.100145] JBD2: Detected IO errors while flushing file data on dm-1-8 2021-03-24T21:05:09.372772+01:00 geneious kernel: [2159846.877201] JBD2: Detected IO errors while flushing file data on dm-1-8 2021-03-24T21:06:39.943519+01:00 geneious kernel: [2159937.381068] JBD2: Detected IO errors while flushing file data on dm-1-8 2021-03-24T21:07:42.364311+01:00 geneious kernel: [2159999.793805] JBD2: Detected IO errors while flushing file data on dm-1-8 2021-03-24T21:07:57.822133+01:00 geneious kernel: [2160015.291776] JBD2: Detected IO errors while flushing file data on dm-1-8 First i'm wondering: what is dm-1-8 ? I don't have a device like that. geneious:~ # find /dev -iname '*dm*' /dev/dm-1 /dev/dm-0 /dev/disk/by-id/dm-uuid-LVM-a9Cy1cweHgXlAEECqZL5KZBfnuigUG6lq0ntdZJxxLIIp5G8XihsuYrTbx7Rs0vc /dev/disk/by-id/dm-name-vg_local-lv_var /dev/disk/by-id/dm-uuid-LVM-a9Cy1cweHgXlAEECqZL5KZBfnuigUG6l3fdsOpBFoDWral3Fa7c6ZeYECmLd6FFj /dev/disk/by-id/dm-name-vg_local-lv_root /dev/cpu_dma_latency I just find /proc/fs/jbd2/dm-1-8. There is a file /proc/fs/jbd2/dm-1-8/info: 453005 transactions (319055 requested), each up to 8192 blocks average: 0ms waiting for transaction 12ms request delay 5124ms running transaction 0ms transaction was being locked 0ms flushing data (in ordered mode) 44ms logging transaction 8031us average transaction commit time 64 handles per transaction 5 blocks per transaction 6 logged blocks per transaction What is that ? The logfile says also something about dm-0-8: 2021-03-24T21:03:30.289644+01:00 geneious kernel: [2159747.796405] CPU: 0 PID: 457 Comm: jbd2/dm-0-8 Not tainted 4.12.14-122.57-default #1 SLE12-SP5 geneious:~ # find / -iname dm-0-8 /proc/fs/jbd2/dm-0-8 geneious:~ # ll /proc/fs/jbd2/dm-0-8 total 0 -r--r--r-- 1 root root 0 Mar 29 12:56 info geneious:~ # cat /proc/fs/jbd2/dm-0-8/info 7356 transactions (556 requested), each up to 8192 blocks average: 0ms waiting for transaction 20ms request delay 5628ms running transaction 4ms transaction was being locked 0ms flushing data (in ordered mode) 132ms logging transaction 134769us average transaction commit time 52 handles per transaction 18 blocks per transaction 19 logged blocks per transaction geneious:~ # I assume i have a harddisk problem. I'm checking currently the SAN with its own tools, via a web interface. Afterwards i want to stop the domain, boot it with a live cd and run badblocks and fsck.ext3. What else can i do ? Bernd -- Bernd Lentes System Administrator Institute for Metabolism and Cell Death (MCD) Building 25 - office 122 HelmholtzZentrum München bernd.lentes(a)helmholtz-muenchen.de phone: +49 89 3187 1241 phone: +49 89 3187 3827 fax: +49 89 3187 2294 http://www.helmholtz-muenchen.de/mcd Public key: 30 82 01 0a 02 82 01 01 00 b3 72 3e ce 2c 0a 6f 58 49 2c 92 23 c7 b9 c1 ff 6c 3a 53 be f7 9e e9 24 b7 49 fa 3c e8 de 28 85 2c d3 ed f7 70 03 3f 4d 82 fc cc 96 4f 18 27 1f df 25 b3 13 00 db 4b 1d ec 7f 1b cf f9 cd e8 5b 1f 11 b3 a7 48 f8 c8 37 ed 41 ff 18 9f d7 83 51 a9 bd 86 c2 32 b3 d6 2d 77 ff 32 83 92 67 9e ae ae 9c 99 ce 42 27 6f bf d8 c2 a1 54 fd 2b 6b 12 65 0e 8a 79 56 be 53 89 70 51 02 6a eb 76 b8 92 25 2d 88 aa 57 08 42 ef 57 fb fe 00 71 8e 90 ef b2 e3 22 f3 34 4f 7b f1 c4 b1 7c 2f 1d 6f bd c8 a6 a1 1f 25 f3 e4 4b 6a 23 d3 d2 fa 27 ae 97 80 a3 f0 5a c4 50 4a 45 e3 45 4d 82 9f 8b 87 90 d0 f9 92 2d a7 d2 67 53 e6 ae 1e 72 3e e9 e0 c9 d3 1c 23 e0 75 78 4a 45 60 94 f8 e3 03 0b 09 85 08 d0 6c f3 ff ce fa 50 25 d9 da 81 7b 2a dc 9e 28 8b 83 04 b4 0a 9f 37 b8 ac 58 f1 38 43 0e 72 af 02 03 01 00 01

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vcenter on esxi on KVM on RHEL8
by Nicholas Hardiman 29 Mar '21

29 Mar '21

I tried something new at the weekend - I created a lab for ansible experiments. One PC, two ESXi VMs, some nested guests. Is this a sensible thing to attempt? vcenter ubuntu1 ubuntu2 ------- ------- ------- ESXi1 ESXI2 ---------------- ------------- KVM -------------------------------- RHEL 8 -------------------------------- ASUS PN50 Everything within ESXi1 works fine, but communication with the outside world is not fine. Before I get into troubleshooting details, I thought I'd just check if this is a reasonable thing to do, or if I'm heading in the wrong direction. Thanks, Nick -- Nick Hardiman, RHCA Senior Consultant Red Hat <https://www.redhat.com/> nhardima(a)redhat.com M: 07585-206195 Upcoming PTO: - Upcoming Training: Mon 8 - Fri 12 March <https://www.redhat.com/>

1 0

Packets dropped by virtual NICs
by Silvia Fichera 29 Mar '21

29 Mar '21

Hi all, I want to use tc qdisc settings in a network coposed of several qemu VMs, connected through bridges and tap interfaces. I generate traffic with a spirent. Everything is fine when the scheduling discipline is not installed but when I run the command to set taprio queues traffic on the VM's NIC the traffic is dropped, i can send max 1mbps. I think that there is something missing in the virtual NIC configuration or setup. With ethtool i can see that queues are configured. I've also noticed the BQL equals to 0, that is different than the physical machine (BQL=18600) where everything works correctly. I've read that it could be because NIC drivers do not support that setting. Do you have any suggestions? Thanks you all Silvia

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Question about the Qos support status for different type interfaces
by Yalan Zhang 29 Mar '21

29 Mar '21

Hi there, I have a question about the Qos support status for different type interfaces. Some types of interface do not support Qos, such as hostdev, user type, mcast type, but the behavior are different, for hostdev, the guest can not start with a meaningful error message, but for other types, vm can start successfully with a warning message in the libvirtd log. I doubt that if it is necessary to keep the behavior consistent for these different types? There are 2 history bugs for them, I should have thought further and asked early when testing the bugs. Bug 1319044 <https://bugzilla.redhat.com/show_bug.cgi?id=1319044> - log error when <bandwidth> requested on a <interface type='hostdev'> Bug 1524230 <https://bugzilla.redhat.com/show_bug.cgi?id=1524230> - vhostuser type interface do not support bandwidth, but no warning message Thank you for looking into this and very appreciate your feedback! 1. start vm with user type interface set with Qos: <interface type='user'> <mac address='52:54:00:3e:ec:14'/> <bandwidth> <inbound average='1000' peak='5000' burst='5120'/> <outbound average='128' peak='256' burst='256'/> </bandwidth> <model type='rtl8139'/> <address type='pci' domain='0x0000' bus='0x07' slot='0x01' function='0x0'/> </interface> # cat /var/log/libvirt/libvirtd.log | grep bandwidth 2021-03-26 10:47:11.452+0000: 20185: warning : qemuBuildInterfaceCommandLine:8223 : setting bandwidth on interfaces of type 'user' is not implemented yet 2. start with hostdev type interface with Qos setting: <interface type='hostdev' managed='yes'> <mac address='52:54:00:07:27:b0'/> <source> <address type='pci' domain='0x0000' bus='0x82' slot='0x10' function='0x6'/> </source> <bandwidth> <inbound average='1000' peak='5000' burst='5120'/> <outbound average='128' peak='256' burst='256'/> </bandwidth> <address type='pci' domain='0x0000' bus='0x01' slot='0x00' function='0x0'/> </interface> # virsh start rh error: Failed to start domain 'rh' error: unsupported configuration: interface 52:54:00:07:27:b0 - bandwidth settings are not supported for hostdev interfaces ------- Best Regards, Yalan Zhang IRC: yalzhang

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Incremental backup utility
by Michael Ablassmeier 28 Mar '21

28 Mar '21

hi users, i have started a project on github that aims to create a small backup utility, supporting the new changed block tracking features. If anyone wants to give it a try and has some suggestions, here is the link: https://github.com/abbbi/virtnbdbackup bye, - michael

1 0

infinite lease time
by Francesc Guasch 23 Mar '21

23 Mar '21

Hi. First of all thanks for this great project and specially for keeping the Perl library. I need to keep the IP address of the virtual machines the same as long as possible. dnsmasq provides a setting for lease time. It can be set to infinite, but not from within libvirt. I found this patch from 2016. > https://listman.redhat.com/archives/libvir-list/2016-October/msg00561.html But it looks like it never made to libvirt. Some time ago I made it work changing dnsmasq/default.conf. Then we made it immutable with chattr. This no longer works because libvirt refuses to start dnsmasq unless it can write to it. Fair enough. I've seen I can add manual IP addresses as stated here: https://wiki.libvirt.org/page/Networking This is ok, but it would be a considerable amount of work, requiring lots of manual labour. Is there a way to set the lease time from libvirt ? Thank you !

2 3

virsh capabilities does not include qemu
by shafnamol N 23 Mar '21

23 Mar '21

Hi, I am new to Libvirt and Qemu.I have installed Libvirt 7.1.0 and qemu-kvm 4.2.0. I configured and built libvirt based on instructions from https://libvirt.org/compiling.html. But when i tried to create a VM using virsh it shows the following error: # virsh create /home/abc.xml error: Failed to create domain from /home/abc.xml error: invalid argument: could not find capabilities for arch=x86_64 domaintype=kvm When i check the hypervisor capabilities ,it doest show qemu in guest domain type. # virsh capabilities .................................... ..................................... </host> <guest> <os_type>exe</os_type> <arch name='x86_64'> <wordsize>64</wordsize> <emulator>/usr/local/libexec/libvirt_lxc</emulator> <domain type='lxc'/> </arch> </guest> <guest> <os_type>exe</os_type> <arch name='i686'> <wordsize>32</wordsize> <emulator>/usr/local/libexec/libvirt_lxc</emulator> <domain type='lxc'/> </arch> </guest> </capabilities> I have restarted libvirt to get the qemu support,but it is not shown in capabilities list.What will be the problem? Thanks for the help in advance....

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Access to an OCFS2 Partition outside the VM
by Lentes, Bernd 18 Mar '21

18 Mar '21

Hi, i'm thinking about installing two Ubuntu versions on one pc, one as a host system with KVM, the other in a virtual domain. I need access from both to several OCFS2 partitions with big amount of data. The partitions are on harddisks attached to that pc. Is it possible to access an OCFS2 partition which is outside the domain ? And if yes how can i do that ? I know that i have to configure OCFS2 and that i need DLM. Buth systems have network, that shouldn't be the problem. Bernd -- Bernd Lentes System Administrator Institute for Metabolism and Cell Death (MCD) Building 25 - office 122 HelmholtzZentrum München bernd.lentes(a)helmholtz-muenchen.de phone: +49 89 3187 1241 phone: +49 89 3187 3827 fax: +49 89 3187 2294 http://www.helmholtz-muenchen.de/mcd Helmholtz Zentrum MÃ¼nchen Helmholtz Zentrum Muenchen Deutsches Forschungszentrum fuer Gesundheit und Umwelt (GmbH) Ingolstaedter Landstr. 1 85764 Neuherberg www.helmholtz-muenchen.de Aufsichtsratsvorsitzende: MinDir.in Prof. Dr. Veronika von Messling Geschaeftsfuehrung: Prof. Dr. med. Dr. h.c. Matthias Tschoep, Kerstin Guenther Registergericht: Amtsgericht Muenchen HRB 6466 USt-IdNr: DE 129521671

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Updating dnsmasq options with virsh net-update
by Alex Crawford 18 Mar '21

18 Mar '21

I'm trying to take advantage of libvirt's support for passing through options to dnsmasq <https://libvirt.org/formatnetwork.html#elementsNamespaces>, but I'm having trouble getting it to take effect. I have a network already created and I'm trying to use net-update to add the options, but it's not clear to me what section I should specify. By the way, is there a good way to list the available sections? I've been resorting to reading the code <https://gitlab.com/libvirt/libvirt/-/blob/18d0f2f9569edf3c26d912a7d8974a54b…>. Working in a different direction, I tried using net-edit to make the changes but they seem to have been silently discarded: $ virsh -c qemu:///system net-edit crawford-libvirt-67v2h Network crawford-libvirt-67v2h XML configuration edited. $ virsh -c qemu:///system net-dumpxml crawford-libvirt-67v2h | grep --count <my changes> 0 Can anyone tell me what I'm doing wrong or how this feature was intended to be used? Thank you. -Alex

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Question about migrate the vm with host-passthrough cpu
by Guoyi Tu 17 Mar '21

17 Mar '21

Hi there, Sorry to bother you, but could I ask you a question about the live migration of virtual machine configured with host-passthough cpu, it confuse me a lot. Here i have two hosts with different cpu, and the cpu feature set of old host is subset of the new one (by virsh cpu-compare). If the vm was first started on the old host,is it safe to migrate the vm between the two hosts back and forth with the vm always keep running? I've test the case in my environment, and the migration succeeds, the cpu family/model/stepping and features of lscpu in Guest OS is the same. -- Best Regards, Guoyi Tu

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Using cgroups in QEMU hooks
by Melissa Nuño 17 Mar '21

17 Mar '21

Hi all, I'm creating a device during the prepare hook, and would like to add it to the device.allow file for the VM. The cgroup doesn't exist during the prepare hook or the start hook and will fail with an "Operation not permitted" error. I can add the expected path to qemu.conf and restart libvirtd, but this isn't very flexible since I'd have to do it for each device for each VM I create. All of the other libvirt cgroups seem to allow all devices, so I'm not seeing where the VM cgroup is getting its initial list. Is there a way to access the cgroup for a VM before it has started? I can't even predict where it should be since it contains the domain ID. Thanks!

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Re: Issue
by Samuel Thampy 12 Mar '21

12 Mar '21

Is there any additional info anyone who needs? ________________________________ From: Samuel Thampy <samjiks(a)hotmail.com> Sent: 03 March 2021 22:11 To: libvirt-users(a)redhat.com <libvirt-users(a)redhat.com> Subject: Issue I have a storage backend san disks, I have five servers which is KVM hosted guests. I am looking to clone an image of a guest machine, so I can use a new VM form the image on a different server.. I am not sure what the best way. But when I do that, I get a memory error, and need to xfs_repair and damages the original machine. My steps are One vm machine on the same server * dd create original vm to template.img * lvcreate -L 9G -n <vol-name> <pool> * dd template.img to /dev/<pool>/<vol-name> * virsh define <vm_name>.xml another vm machine on the secondary server * copy template.img to another server * lvcreate -L 9G -n <vol-name> <pool> * dd if=template.img of=/dev/<pool>/<vol-name> * virsh define <vm_name>.xml May I know the steps are missing something because both are getting corrupted. Thanks for your help. Regards Samuel Thampy

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Bridge and VLAN trunk
by Gionatan Danti 11 Mar '21

11 Mar '21

Dear list, I am a question about the best use of bridge, vlan trunk and libvirt. When dealing with virtual machies bound to specific vlan, I generally use a straightforward approach: eth -> bridge -> vm (for untagged traffic) eth -> eth.10 -> bridge -> vm eth -> eth.nn -> bridge -> vm Now I am faced with enabling vlan trunking for a specific vm (a virtualized firewall). The simpler approach would be: eth -> bridge -> vm (for the vm needing trunk) eth -> bridge.10 -> macvtap -> vm The issue with the above method is that any VM on the main untagged vlan needs to be bound to the "plain" bridge, having access to *any* traffic of *any* other vlan. If this is ok (and the desired behavior) for the firewall, it is clearly wrong for the other VMs. A simple fix would be to use ebtables to block/drop vlan tagged traffic on the main bridge for any virtual adapter except the required one (ie: the firewall virtual interface). It works, but I wounder if other preferred approaches exists. For example, I tested another more convoluted setup: eth -> bridge -> firewall vm eth -> bridge.10 -> macvtap -> vm eth -> bridge -> veth0 -> veth1 -> other bridge with vlan filtering on -> vm The last row show the use of veth virtual interface, configurable via ip link. Enabling vlan filtering on the second bridge (rather than on the first) is to keep vlan filtering simple: rathen than enabling all required vlan on the first bridge, I simply enable only untagged traffic on the second one. Does libvirt support bridge vlan filtering natively? Reading the docs, it seems to the supported only on OpenVSwitch or SRV-IO based adapter. 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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Snapshot operation aborted and volume usage
by Liran Rotenberg 11 Mar '21

11 Mar '21

We recently had this bug[1]. The thought that came from it is the handling of error code after running virDomainSnapshotCreateXML, we encountered VIR_ERR_OPERATION_ABORTED(78). Apparently, the new volume is in use. Are there cases where this will happen and the new volume won't appear in the volumes chain? Can we detect / know when? Thinking aloud, if we can detect such cases we can prevent rolling back by reporting it back from VDSM to ovirt. Or, if it can't be detected to go on the safe side in order to save data corruption and prevent the rollback as well. Currently, in ovirt, if the job is aborted, we will look into the chain to decide whether to rollback or not. Regards, Liran. [1] - https://bugzilla.redhat.com/show_bug.cgi?id=1916122

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virsh snapshot-create-as with quiesce option times out
by David Wells 05 Mar '21

05 Mar '21

Hi all! I'm still working on the live backup of a couple vm's and what happens most of the times es that when I execute virsh with the snapshot-create-as with the --quiesce option the process finishes with an error that reads > error: Timed out during operation: cannot acquire state change lock I tried turning up the debug level but found nothing that appears to be of interest and I can connect successfully to the qemu guest agent since the following command returns the correct value > sudo /usr/sbin/virsh domfsinfo slackware-current > Mountpoint Name Type Target > ------------------------------------------------------------------- > / vda1 ext4 vda I also tried running the qemu-ga agent on the guest with debugging enabled and when I issue this last command I can see the agent talking to the host but when I issue the quiesce option the guest agent shows nothing at all. Is this by any chance a known bug? Is there something obvious I'm missing? What else can I provide to help debug this issue? Thanks in advance! Best regards, David Wells.

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virtio model type and netfilter masquerade not being applied
by Brad Jennings 04 Mar '21

04 Mar '21

Quick question for anyone in the know, I have a fairly basic setup (at least I think it is?) with an openvswitch, and the br0 port has an IP assigned in the same subnet as the VM to act as a gateway. |------ovs-------| eno2 <-- |--br0 | |--vnet0 - VM | |------------------| I would like the VM (vnet0) to use br0 as a gateway which local connectivity wise seems fine but the internet is a bit odd. I can ping for example 1.1.1.1 dns without any issues but anying udp/tcp is a no go. I checked the physical hosts interface(eno2) and br0 to find that the VM's packets were successfully heading to br0 but when leaving the physical host(eno2) the tcp/udp packets weren't being masqueraded. The rule is pretty straightforward and to test I plugged another device into the eno1 afxdp port and had no connectivity issues and packets were being masqueraded fine. I tried to set trustGuestRxFilters='yes' but that didn't work and the same state remained, the only thing that worked was using the "rtl8139" model type. I always remember using 'virtio' in the past and I must be missing something crucial in the somewhat lengthy libvirt documentation. Would be super helpful if someone can shed some light on this ? and possibly if I should be using virtio or the realtek driver ? Thanks ! (config below) Iptables: sudo iptables -t nat -A POSTROUTING -o eno2 -j MASQUERADE ovs-vsctl show ec13c3e2-6159-4019-984e-36cc90c59075 Bridge br0 fail_mode: standalone datapath_type: netdev Port vnet0 Interface vnet0 Port eno1 Interface eno1 type: afxdp Port br0 Interface br0 type: internal instance domain xml <interface type='bridge'> <mac address='52:54:00:77:fc:70'/> <source bridge='br0'/> <virtualport type='openvswitch'> <parameters interfaceid='2124ef39-e244-434c-8339-d2aa04d0d888'/> </virtualport> <model type='virtio'/> #rtl8139 works. <address type='pci' domain='0x0000' bus='0x02' slot='0x01' function='0x0'/> </interface>

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Some confusion about lsilogic controller
by xingchaochao 03 Mar '21

03 Mar '21

Hello, I have been confused by such a phenomenon recently. Libvirt is the master branch , and the VM is centos8.2(kernel is 4.18.0-193.el8.aarch64). When I hot-plug the scsi disk for a virtual machine without a virtio-scsi controller, libvirt will automatically generate an lsilogic controller for the scsi disk. <disk type='file' device='disk'> <driver name='qemu' type='qcow2' cache='none' io='native'/> <source file='/Images/xcc/tmp.img'/> <backingStore/> <target dev='sdt' bus='scsi'/> <address type='drive' controller='0' bus='0' target='0' unit='0'/> </disk> linux-upcHIq:/Images/xcc # virsh list Id Name State ---------------------- 12 g1 running linux-upcHIq:/Images/xcc # virsh attach-device g1 disk.xml Device attached successfully linux-upcHIq:/Images/xcc # virsh dumpxml g1 | grep scsi <target dev='sdt' bus='scsi'/> <alias name='scsi0-0-0'/> <controller type='scsi' index='0' model='lsilogic'> <alias name='scsi0'/> But this scsi disk cannot be found through the lsblk command inside the virtual machine. [root@localhost ~]# lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT vda 252:0 0 20G 0 disk ├─vda1 252:1 0 600M 0 part /boot/efi ├─vda2 252:2 0 1G 0 part /boot └─vda3 252:3 0 18.4G 0 part ├─cl-root 253:0 0 16.4G 0 lvm / └─cl-swap 253:1 0 2G 0 lvm [SWAP] After hot unplugging the scsi disk, I performed the hot unplug operation of the lsilogic controller. libvirt shows "Device detached successfully", but in fact, the lsilogic controller is not removed from the live XML and persistent XML. Through "virsh dumpxml vmname" and "virsh edit vmname", I can see <controller type='scsi' index='0' model='lsilogic'> is always there. linux-upcHIq:/Images/xcc # virsh detach-device g1 disk.xml Device detached successfully linux-upcHIq:/Images/xcc # virsh dumpxml g1 | grep scsi <controller type='scsi' index='0' model='lsilogic'> <alias name='scsi0'/> linux-upcHIq:/Images/xcc # linux-upcHIq:/Images/xcc # cat lsi.xml <controller type='scsi' index='0' model='lsilogic'> <alias name='scsi0'/> <address type='pci' domain='0x0000' bus='0x03' slot='0x05' function='0x0'/> </controller> linux-upcHIq:/Images/xcc # virsh detach-device g1 lsi.xml Device detached successfully linux-upcHIq:/Images/xcc # virsh dumpxml g1 | grep scsi <controller type='scsi' index='0' model='lsilogic'> <alias name='scsi0'/> I am confused, why libvirt chooses to generate an lsilogic controller for the scsi disk when there is no scsi controller, instead of directly reporting an error and exiting the hot plug operation. After all, the scsi disk based on the lsilogic controller is not perceived inside the virtual machine, and lsilogic will remain in the XML file of the virtual machine.

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Live backups create-snapshot-as and memspec
by David Wells 01 Mar '21

01 Mar '21

Hi all! I've been using libvirt for some time and until now I have treated backups of virtual computers as if they where physical computers installing the backup client on the guest. I am now however facing the need to backup a couple a couple of guest at the host level so I've been trying to catch up by reading, googling and by trial and error too. Up to now I've been able to backup a live machine whith a command like the following > virsh snapshot-create-as --domain test --name backup --atomic > --diskspec vda,snapshot=external --disk-only This command creates a file test.backup and in the meantime I can backup the original test.qcow2 but for what I saw this disk image is in a "dirty" state, as if the machine I could restore from this file had been turned off whithout a proper shutdown. I know that I can later restore the machine to its original state by issuing a command like this > virsh blockcommit --domain test vda --active --pivot > virsh snapshot-delete test --metadata backup I have seen that it is possible to create the snapshot using a memspec parameter which would make the backup of the guest as if it where in a clean state, however I haven't found the equivalent of the blockcommit for the memory file, in a sort of speak, to be able to restore the guest to it's original state. Thank you very much! Best regards. David Wells.

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Upgrading the host
by Marcin Struzak 19 Feb '21

19 Feb '21

Hello-- I'm planning on upgrading the OS on my host machine by doing manual re-installation, which will trigger an upgrade of libvirt from 1.1.3 to 6.1.0. Hardware, storage volumes & paths, etc., will be the same after upgrade. I was going to redefine & start everything from .xml files, starting with the network virsh net-define <network XML> virsh net-autostart <network> virsh net-start <network> and following with all the guests virsh define <domain XML> virsh autostart <domain> virsh start <domain> I have the following questions: 1. Do I need to generate XML dumps manually, or is it ok to use the ones from host's /etc/libvirt? 2. Do I need to define & start storage pools & volumes explicitly, or will they be picked up from domain definitions? 3. Anything else I should worry about or prepare ahead? --Marcin

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