July 2020 - Users - libvirt List Archives

[libvirt-users] [virtual interface] detach interface during boot succeed with no changes
by Yalan Zhang 08 Sep '22

08 Sep '22

Hi guys, when I detach an interface from vm during boot (vm boot not finished), it always fail. I'm not sure if there is an existing bug. I have confirmed with someone that for disk, there is similar behavior, if this is also acceptable? # virsh destroy rhel7.2; virsh start rhel7.2 ;sleep 2; virsh detach-interface rhel7.2 network 52:54:00:98:c4:a0; sleep 2; virsh dumpxml rhel7.2 |grep /interface -B9 Domain rhel7.2 destroyed Domain rhel7.2 started Interface detached successfully <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/> </controller> <interface type='network'> <mac address='52:54:00:98:c4:a0'/> <source network='default' bridge='virbr0'/> <target dev='vnet0'/> <model type='rtl8139'/> <alias name='net0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> When I detach after the vm boot, expand the sleep time to 10, it will succeed. # virsh destroy rhel7.2; virsh start rhel7.2 ;sleep 10; virsh detach-interface rhel7.2 network 52:54:00:98:c4:a0; sleep 2; virsh dumpxml rhel7.2 |grep /interface -B9 Domain rhel7.2 destroyed Domain rhel7.2 started Interface detached successfully ------- Best Regards, Yalan Zhang IRC: yalzhang Internal phone: 8389413

3 4

Set hostname of guest during installation time
by john doe 05 Nov '20

05 Nov '20

Hi, I would like to set the hostname when installing a guest, with the below command the hostname is not set to 'try06' in the guest: virt-install --name=try06 --graphic none --pxe --network bridge=virbr0 How can I set the hostname of the guest during installation time? I realy appriciate the support I'm getting in here, I'm fairly new to libvirt. -- John Doe

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[libvirt-users] Live migrate + change interface name
by Marc Roos 07 Oct '20

07 Oct '20

Is it possible to do a live migrate of a guest, having on the from host a source_device=eth2 and to host a source_dev=eth1?

2 4

[libvirt-users] Add Virtlyst to the list of libvirt users
by Daniel Nicoletti 23 Sep '20

23 Sep '20

Hi, I've just released v1.0.0 of Virtlyst[1] a web tool to manage VMs using Qt/C++/Cutelyst https://dantti.wordpress.com/2018/04/19/announcing-virtlyst-a-web-interface… Thanks. 1 - https://github.com/cutelyst/Virtlyst -- Daniel Nicoletti KDE Developer - http://dantti.wordpress.com

4 5

Two questions about NVDIMM devices
by Milan Zamazal 14 Sep '20

14 Sep '20

Hi, I've met two situations with NVDIMM support in libvirt where I'm not sure all the parties (libvirt & I) do the things correctly. The first problem is with memory alignment and size changes. In addition to the size changes applied to NVDIMMs by QEMU, libvirt also makes some NVDIMM size changes for better alignments, in qemuDomainMemoryDeviceAlignSize. This can lead to the size being rounded up, exceeding the size of the backing device and QEMU failing to start the VM for that reason (I've experienced that actually). I work with emulated NVDIMM devices, not a bare metal hardware, so one might argue that in practice the device sizes should already be aligned, but I'm not sure it must be always the case considering labels or whatever else the user decides to set up. And I still don't feel very comfortable that I have to count with two internal size adjustments (libvirt & QEMU) to the `size' value I specify, with the ultimate goal of getting the VM started and having the NVDIMM aligned properly to make (non-NVDIMM) memory hot plug working. Is the size alignment performed by libvirt, especially rounding up, completely correct for NVDIMMs? The second problem is that a VM fails to start with a backing NVDIMM in devdax mode due to SELinux preventing access to the /dev/dax* device (it doesn't happen with any other NVDIMM modes). Who should be responsible for handling the SELinux label appropriately in that case? libvirt, the system administrator, anybody else? Using <seclabel> in NVDIMM's source doesn't seem to be accepted by the domain XML schema. Thanks, Milan

5 11

Problem with xen config
by Christoph 15 Aug '20

15 Aug '20

Hi all, I 've such a config on xen (4.14): name = "marax.chao5.int" uuid = "e0de3cb7-3937-417d-8d63-b0993b377b6a" maxmem = 16384 memory = 16384 kernel = '/usr/lib64/xen/boot/hvmloader' vcpus = 16 rtc_timeoffset = 0 localtime = 1 on_poweroff = "destroy" on_reboot = "restart" on_crash = "restart" vif = [ "mac=00:16:3e:05:01:10,bridge=xenbr5,script=vif-bridge,model=e1000" ] parallel = "none" serial = "none" type = "hvm" loader = "/usr/lib64/xen/boot/hvmloader" disk = [ "phy:/dev/mapper/marax_c,hda,rw", "phy:/dev/vg_lilith/lv_marax_d,hdb,rw" ] max_grant_frames = "128" pci = [ "01:00.0", "01:00.1", "01:00.2", "01:00.3", "00:1f.3", "05:00.0" ] pci_permissive = 1 keymap = "de" vnclisten="0.0.0.0" pci_power_mgmt=1 xen_platform_pci=1 pci_msitranslate=1 viridian=1 hpet=1 acpi=1 apic=1 pae=1 I want to convert it to a xml format for use it with libvirt/virsh but I get an error: "error: An error occurred, but the cause is unknown" If I comment out the line with pci = [ "01:00.0", "01:00.1", "01:00.2", "01:00.3", "00:1f.3", "05:00.0" ] then it works but I dont see the settings like xen_platform_pci=1 pci_msitranslate=1 pci_permissive = 1 max_grant_frames = "128 and the pci passthrough devices are not there... Does libvirt doesnt support such a config? -- ------ Greetz

3 9

guest-fsfreeze-freeze freezes all mounted block devices
by Marc Roos 09 Aug '20

09 Aug '20

I wondered if anyone here can confirm that virsh qemu-agent-command domain '{"execute":"guest-fsfreeze-freeze"}' Freezes all mounted block devices filesystems. So if I use 4 block devices they are all frozen for snapshotting. Or just the root fs?

5 15

[libvirt-users] Question about disabling UFO on guest
by Bao Nguyen 05 Aug '20

05 Aug '20

Hello everyone, I would like to ask a question regarding to disable UFO of virtio vNIC in my guest. I have read the document at https://libvirt.org/formatdomain.html *host* The csum, gso, tso4, tso6, ecn and ufo attributes with possible values on and off can be used to turn off host offloading options. By default, the supported offloads are enabled by QEMU. *Since 1.2.9 (QEMU only)* The mrg_rxbuf attribute can be used to control mergeable rx buffers on the host side. Possible values are on (default) and off. *Since 1.2.13 (QEMU only)* *guest* The csum, tso4, tso6, ecn and ufo attributes with possible values on and off can be used to turn off guest offloading options. By default, the supported offloads are enabl ed by QEMU. *Since 1.2.9 (QEMU only)* Then I disabled UFO on my vNIC on guest as the following configuration <devices> <interface type='network'> <source network='default'/> <target dev='vnet1'/> <model type='virtio'/> <driver name='vhost' txmode='iothread' ioeventfd='on' event_idx='off' queues='5' rx_queue_size='256' tx_queue_size='256'> *<host gso='off' ufo='off' />* *<guest ufo='off'/>* </driver> </interface> </devices> Then I reboot my node to get the change effect and it works. However, can I disable the UFO without touching the host OS? or it always has to disable on both host and guest like that? Thanks, Brs, Natsu

2 1

Cannot pass secret id for backing file after taking external snapshot on encrypted qcow2 file
by yaohua.wu＠zstack.io 03 Aug '20

03 Aug '20

Hi， I used 'virsh snapshot-create' create an encrypted external snapshot, when I try to use 'qemu-img check' top file, found no entrance to pass backing-file's secret-id 1、Version centos-release-8.2-2.2004.0.1.el8.x86_64 libvirt.x86_64 6.0.0-17.el8 qemu-kvm.x86_64 15:4.2.0-19.el82、Reproduce Steps 1)Create an encrypted qcow2 qemu-img create --object secret,id=sec0,data=123456 -f qcow2 -o encrypt.format=luks,encrypt.key-secret=sec0 first.qcow2 1G 2)Create external snapshot with 'encrypted' xml # cat snap.xml <domainsnapshot> <disks> <disk name='hdc' snapshot='no'/> <disk name='vdb' snapshot='external'> <source file='/root/first-snapshot.qcow2'> <encryption format='luks'> <secret type='passphrase' uuid='f52a81b2-424e-490c-823d-6bd4235bc572'/> </encryption> </source> </disk> </disks> </domainsnapshot> # virsh dumpxml test-vm | awk '/<disk/,/<\/disk/' <disk type='file' device='disk'> <driver name='qemu' type='qcow2'/> <source file='/root/first-snapshot.qcow2' index='5'/> <backingStore type='file' index='2'> <format type='qcow2'/> <source file='/root/first.qcow2'> <encryption format='luks'> <secret type='passphrase' uuid='f981dd17-143f-45bc-88e6-222222222222'/> </encryption> </source> <backingStore/> </backingStore> <target dev='vdb' bus='virtio'/> <encryption format='luks'> <secret type='passphrase' uuid='f52a81b2-424e-490c-823d-6bd4235bc572'/> </encryption> <alias name='virtio-disk1'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x0a' function='0x0'/> </disk> 3)try to qemu-img check top qcow2 file Note: The secid of the backing file is not recorded, so when I use qemu-img check/etc.. how to pass the secret to qemu of backing files # qemu-img info -U first-snapshot.qcow2 image: first-snapshot.qcow2 file format: qcow2 virtual size: 1 GiB (1073741824 bytes) disk size: 544 KiB encrypted: yes cluster_size: 65536 backing file: /root/first.qcow2 ### backing file: json:{"encrypt.format": "luks", "encrypt.key-secret": "secrete-id"} backing file format: luks Format specific information: compat: 1.1 lazy refcounts: false refcount bits: 16 encrypt: ivgen alg: plain64 hash alg: sha256 cipher alg: aes-256 uuid: e4158089-26e4-433f-990e-1d1d0723feee format: luks cipher mode: xts slots: [0]: active: true iters: 1257888 key offset: 4096 stripes: 4000 [1]: active: false key offset: 262144 [2]: active: false key offset: 520192 [3]: active: false key offset: 778240 [4]: active: false key offset: 1036288 [5]: active: false key offset: 1294336 [6]: active: false key offset: 1552384 [7]: active: false key offset: 1810432 payload offset: 2068480 master key iters: 300073 corrupt: false # qemu-img check -U --object secret,id=sec_1,file=/etc/libvirt/secrets/f52a81b2-424e-490c-823d-6bd4235bc572.base64,format=base64 --image-opts encrypt.format=luks,encrypt.key-secret=sec_1,file.filename=first-snapshot.qcow2 --object secret,id=sec_2,file=/etc/libvirt/secrets/f981dd17-143f-45bc-88e6-222222222222.base64,format=base64 qemu-img: Could not open 'encrypt.format=luks,encrypt.key-secret=sec_1,file.filename=first-snapshot.qcow2': Could not open backing file: Parameter 'key-secret' is required for cipher yaohua.wu(a)zstack.io

2 1

libvirt segfaults with "internal,error: Missing monitor reply object", during block live-migration
by Alex Walender 31 Jul '20

31 Jul '20

Dear libvirt community, Using recent Ubuntu Stein Cloud Packages, we are observing random libvirtd live-migration crashes on the target host. Libvirt is having a SEGFAULT with the qemu driver. Transferring block devices usually works without issues. However, the following memory transfer is causing the target libvirtd randomly to close down its socket, resulting in a roll-backed migration process.I can reproduce this with large VMs, which have a large memory pool. The last error message we see in libvirt logs is: error : qemuMonitorJSONCommandWithFd:315 : internal error: Missing monitor reply object With this, libvirt segfaults and restarts. Before we encountered this issue, we used an older nova-compute package (19.0.3). Not sure if this made a difference with usage of libvirtd-api. After upgrade, we also see a lot of recurring errors during migration: warning : qemuDomainObjBeginJobInternal:7044 : Cannot start job (query, none, none) for domain instance-00008f56; current job is (none, none, migration in) owned by (0 <null>, 0 <null>, 0 remoteDispatchDomainMigratePrepare3Params (flags=0x809b)) for (0s, 0s, 14834s) error : qemuDomainObjBeginJobInternal:7066 : Timed out during operation: cannot acquire state change lock (held by monitor=remoteDispatchDomainMigratePrepare3Params) They don't abort the running migration process, but spam every minute to the systemd journal. Source and destination run the same packages: Ubuntu 18.04.4 LTS (GNU/Linux 4.15.0-99-generic x86_64) OpenStack Stein (Ubuntu Cloud Archive) Libvirt+QEMU_x86 keystone-common 2:15.0.1-0ubuntu1~cloud0 libvirt-daemon 5.0.0-1ubuntu2.6~cloud0 qemu-system-x86 1:3.1+dfsg-2ubuntu3.7~cloud0 neutron-linuxbridge-agent 2:14.2.0-0ubuntu1~cloud0 neutron-plugin-ml2 2:14.2.0-0ubuntu1~cloud0 nova-compute 2:19.2.0-0ubuntu1~cloud0 nova-compute-libvirt 2:19.2.0-0ubuntu1~cloud0 I have attached source/destination debug logs from libvirtd and nova-compute here: https://denzelx.ddns.net/index.php/s/KPJ7vv4aTcb69XD Any help would be nice! Best Regards -- M.Sc Alex Walender de.NBI Cloud Bielefeld Administrator Center for Biotechnology (CeBiTec) University of Bielefeld 33594 Bielefeld Germany room: M3-118 phone: +49 (521) 106 2907

3 3

Routed network can't reach outside network
by Rui Correia 29 Jul '20

29 Jul '20

Greetings folks. I've setup libvirtd on my manjaro linux laptop. Got a couple of VM's running (Win10 and Debian10) through NAT without any issues. This is what the current network diagram looks like and it works fine: +-----------------------------------+ | +---------------------+ | | | +----------+ | | | | |Win 10 VM | | | | | |10.1.1.10 | | | | | +----------+ | | | Laptop | | | | Manjaro | +-------------+ | | | 10.0.0.10 | |Debian 10 VM | | | +-------->+ | |10.1.1.11 | | | | | | +-------------+ | | | | |NAT | | | | |10.1.1.0/24 | | | | +---------------------+ | +------------+ | +-----------------------------------+ |router | | |switch +---+ |10.0.0.0/24 | | +---------+ +------------+ | |Desktop | +-------->+Manjaro | |10.0.0.11| +---------+ But now I need the debian machine to be accessible from another host on the lan 10.0.0.0/24 which of course is outside the host. That network diagram would look like this: +-----------------------------------------+ | +------------------+ | | | +----------+ | | | | |Win 10 VM | | | | | |10.1.1.10 | | | | | NAT +----------+ | | | | 10.1.1.0/24 | | | +------------------+ | | Laptop | +-------->+ Manjaro +------------------------+ | | | 10.0.0.10 | +-------------+ | | | | | |Debian 10 VM | | | | | | |10.2.2.10 | | | | | | Routed +-------------+ | | +------------+ | | | 10.2.2.0/24 | | |router | | | +------------------------+ | |switch +---+ +-----------------------------------------+ |10.0.0.0/24 | | +------------+ | | | +---------+ | |Desktop | +-------->+Manjaro | |10.0.0.11| +---------+ So, I've setup a 'routed network' for the Debian 10 VM but it's not working as I would expect. The host can ping the Debian VM and the Debian VM can ping the host but the Debian VM cannot ping the router 10.0.0.1 or any ip address on the internet. I've been using Virtual Machine Manager to set everything up. And this is how the routed network is configured <network connections="1"> <name>routed</name> <uuid>970a25f7-29b6-4a6b-b890-f593eae4fc15</uuid> <forward dev="wlo1" mode="route"> <interface dev="wlo1"/> </forward> <bridge name="virbr2" stp="on" delay="0"/> <mac address="52:54:00:bf:35:42"/> <domain name="routed"/> <ip address="10.2.2.1" netmask="255.255.255.0"> <dhcp> <range start="10.2.2.2" end="10.2.2.254"/> </dhcp> </ip> </network> Any idea on what i might be doing wrong? Thanks in advance. Cheers Rui Correia

6 9

machinectl does not show libvirtd vms
by Ismael Bouya 28 Jul '20

28 Jul '20

(this is a follow-up of a discussion on IRC with mprivozn) Hello, I’m facing an issue where systemd-machined is not aware of new VMs happening in libvirt (with QEMU). I attached debug logs for a VM starting. To repeat the discussion that happened on IRC: - libvirt config does not specify anything related to cgroup_controllers - cgroups are mounted (mount | grep cgroup is not empty) - in libvirtd.service I see no mention of cgroups (apart from comments related to TasksMax and LimitMEMLOCK) I’m suspecting a packaging issue in my distribution (NixOS) but I’m not really sure where I should look at to solve it. NB: the reason I wanted machinectl was to make use of nsswitch mymachines facilities, which I learnt wouldn’t work anyway. So I’m only reporting it in case something needs to be fixed (probably in my distribution packaging). -- Ismael

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Re: Routed network can't reach outside network
by Rui Correia 23 Jul '20

23 Jul '20

Hi Ken, Of course I did it all by hand. :-D No, I didn't. I'm a fraud. I used http://asciiflow.com/ which asks you to register in order to save your drawings in their cloud. If you don't register, you can still draw and export your drawings, but you can't save them for reusing those later. I see I've missed a couple of posts in this small thread. I was under the impression that I had subscribed to the list but apparently I'm only receiving the messages directly addressed to me. Hence why I took so much time to reply. I'll try to subscribe again. Thank you all in advance. Cheers, Rui Correia On Thu, Jul 23, 2020 at 3:31 PM Marc Roos <M.Roos(a)f1-outsourcing.eu> wrote: > > > > > you must be an ASCII charting demigod. Did you use software to make > those, or do > > them yourselves? Either way, I'm impressed... > > Search for AsciiArtStudio.exe > > > > >

1 0

virt-install missing parameters
by David 22 Jul '20

22 Jul '20

Hello, Hopefully this is the right place to send a question like this... I'm attempting to automate creation of VMs using virt-install and a cloud-init disk image. To get this to work, I need to specify the location of the cloud-init configs by passing smbios key/value pairs. Normally, -smbios is provided to qemu to do this. With virt-install, the Internet says I should use --sysinfo. However, --sysinfo (as well as --qemu-comandline) is reported as an invalid command flag, and it is not present when I look at man virt-install and virt-install --help. I am hoping someone on the list knows why this isn't working or can explain how I might provide the arguments to qemu. The host is Debian 9. It is up-to-date as far as package versions are concerned, as much as Debian 9 can be. I can't find any indication about why the arguments would have been taken away. Thanks!

1 0

host and vm on isolated network, there is ip (via dhcp) but not ping
by daggs 22 Jul '20

22 Jul '20

Greetings, I've setup an vm with openwrt in it, defined a isolated lan between the vm and the host and booted the vm up. I see the vm is up, made sure the vnic is visible in both the host and guest and added it to the br in the guest. I've issued an dhcpd call on the vnic (labeled vnic0) in the host and got an ip, see: dagg@NCC-5001D ~ $ dhcpcd vnet0 DUID 00:01:00:01:23:dd:d8:5b:e0:d5:5e:d9:f2:e2 vnet0: IAID 00:10:20:bf vnet0: rebinding lease of 192.168.1.130 vnet0: probing address 192.168.1.130/24 vnet0: soliciting an IPv6 router vnet0: leased 192.168.1.130 for 43200 seconds vnet0: adding route to 192.168.1.0/24 vnet0: adding default route via 192.168.1.1 forked to background, child pid 26279 dagg@NCC-5001D ~ $ ifconfig virtsw0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 ether 52:54:00:3e:3f:88 txqueuelen 1000 (Ethernet) RX packets 123098 bytes 16327962 (15.5 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 6 bytes 252 (252.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 vnet0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.1.130 netmask 255.255.255.0 broadcast 192.168.1.255 inet6 fe80::fc54:ff:fe10:20bf prefixlen 64 scopeid 0x20<link> ether fe:54:00:10:20:bf txqueuelen 1000 (Ethernet) RX packets 45 bytes 8002 (7.8 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 39 bytes 2676 (2.6 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 dagg@NCC-5001D ~ $ ping 192.168.1.1 PING 192.168.1.1 (192.168.1.1) 56(84) bytes of data. ^C --- 192.168.1.1 ping statistics --- 2 packets transmitted, 0 received, 100% packet loss, time 1018ms the vm's xml can be found at https://pastebin.com/1gXBGcPb virtsw0 is defined as follows: <network connections='1'> <name>virtsw0</name> <uuid>c8eb15a3-cc5c-4bd6-8f3b-5790792ddccc</uuid> <bridge name='virtsw0' stp='on' delay='0'/> <mac address='52:54:00:3e:3f:88'/> </network> the os is gentoo, the versions are libvirt-6.2.0 qemu-5.0.0. I have another server running debian 10 with the same virtsw0 definition, there the connection is working. /var/lib/libvirt/dnsmasq/virtsw0.macs has only [] in it, can that be the issue? Thanks, Dagg.

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dns test 2
by NO SPAM 21 Jul '20

21 Jul '20

please ignore

1 0

incomplete features for external snapshot
by Henry lol 21 Jul '20

21 Jul '20

as far as I know, deleting/reverting features for external snapshot are not being supported for long time. I'm wondering why it takes so long time and what is the main problem even though those tasks can be done manually. thanks.

1 0

dns test
by NO SPAM 20 Jul '20

20 Jul '20

please ignore

1 0

9p file sharing issue
by Johan 19 Jul '20

19 Jul '20

I've run into an issue with 9p file sharing that I suspect is a bug. I'm running some Debian ARM VMs (armhf Ubuntu guests on an aarch64 Debian stretch host in case that matters). I'm using direct kernel boot, so I'm also using 9p host file sharing so that kernel updates from within the guest would work. However, I've noticed that dpkg (the Debian/Ubuntu package manager) fails when writing into a /boot directory that's shared from the host via 9p. Some investigation reveals that this is because dpkg does an openat() call of the type openat(AT_FDCWD, "/boot/vmlinuz-4.15.0-111-generic-lpae.dpkg-new", O_WRONLY|O_CREAT|O_EXCL|O_LARGEFILE, 000); and that it's the 0 permissions mode (last parameter) that causes the call to fail with a "Permission denied" error. A simple test program that does the above openat() call but with another mode (say, 600) works just fine. Some further data: * QEMU runs as the unprivileged user libvirt-qemu (Debian default) * QEMU is version 2.8, libvirt version 3.0.0 * XML snippet for 9p setup: <filesystem type='mount' accessmode='squash'> <source dir='/host/path/boot-test9p'/> <target dir='boot_mount'/> <alias name='fs0'/> <address type='pci' domain='0x0000' bus='0x03' slot='0x01' function='0x0'/> </filesystem> * The 9p filesystem is mounted by this line in /etc/fstab on the guest: boot_mount /boot 9p rw,dirsync,_netdev,relatime,trans=virtio,version=9p2000.L 0 0 The essential problem seems to be that opening a file with a mode of 0 is not compatible with the "squash" 9p access mode. Is this expected? Thank you, Johan

1 0

Unable to decode message length
by Valentin David 16 Jul '20

16 Jul '20

Hello all, I have been trying to get libvirtd to work but when I connect to it with virsh, I get "error : virNetMessageDecodeLength:131 : Unable to decode message length" This happens with libvirt 6.1.0, libtirpc 1.2.6, rpcsvc-proto 1.4.1. I have tried with other versions, but I still get the same error. If anybody has any tip on what to try next, that would be helpful. Thank you in advance. Here is the debug log of libvirtd when I try to connect with virsh: 2020-07-14 16:29:58.220+0000: 5352: info : virEventGLibHandleDispatch:116 : EVENT_GLIB_DISPATCH_HANDLE: watch=2 events=1 cb=0x7f7b55b86c50 opaque=0x556fbcf8b8a0 2020-07-14 16:29:58.220+0000: 5352: info : virObjectNew:250 : OBJECT_NEW: obj=0x556fbcf8d770 classname=virNetSocket 2020-07-14 16:29:58.220+0000: 5352: info : virNetSocketNew:278 : RPC_SOCKET_NEW: sock=0x556fbcf8d770 fd=18 errfd=-1 pid=0 localAddr=127.0.0.1;0, remoteAddr=127.0.0.1;0 2020-07-14 16:29:58.220+0000: 5352: info : virObjectNew:250 : OBJECT_NEW: obj=0x556fbcf8da50 classname=virNetServerClient 2020-07-14 16:29:58.220+0000: 5352: info : virObjectRef:385 : OBJECT_REF: obj=0x556fbcf8d770 2020-07-14 16:29:58.220+0000: 5352: info : virEventGLibTimeoutAdd:341 : EVENT_GLIB_ADD_TIMEOUT: timer=1 interval=-1 cb=0x7f7b55b8d490 opaque=0x556fbcf8da50 ff=(nil) 2020-07-14 16:29:58.220+0000: 5352: info : virNetServerClientNewInternal:421 : RPC_SERVER_CLIENT_NEW: client=0x556fbcf8da50 sock=0x556fbcf8d770 2020-07-14 16:29:58.220+0000: 5352: info : virObjectRef:385 : OBJECT_REF: obj=0x556fbcf8da50 2020-07-14 16:29:58.220+0000: 5352: info : virObjectRef:385 : OBJECT_REF: obj=0x556fbcf8d770 2020-07-14 16:29:58.220+0000: 5352: info : virEventGLibHandleAdd:160 : EVENT_GLIB_ADD_HANDLE: watch=11 fd=18 events=1 cb=0x7f7b55b86c50 opaque=0x556fbcf8d770 ff=0x7f7b55b86c00 2020-07-14 16:29:58.220+0000: 5352: info : virObjectRef:385 : OBJECT_REF: obj=0x556fbcf8da50 2020-07-14 16:29:58.220+0000: 5352: info : virNetServerCheckLimits:280 : Re-enabling services 2020-07-14 16:29:58.220+0000: 5352: info : virEventGLibHandleUpdate:194 : EVENT_GLIB_UPDATE_HANDLE: watch=2 events=1 2020-07-14 16:29:58.220+0000: 5352: info : virObjectNew:250 : OBJECT_NEW: obj=0x556fbcf8e330 classname=virKeepAlive 2020-07-14 16:29:58.220+0000: 5352: info : virKeepAliveNew:208 : RPC_KEEPALIVE_NEW: ka=0x556fbcf8e330 client=0x556fbcf8da50 2020-07-14 16:29:58.220+0000: 5352: info : virObjectRef:385 : OBJECT_REF: obj=0x556fbcf8da50 2020-07-14 16:29:58.220+0000: 5352: info : virObjectUnref:347 : OBJECT_UNREF: obj=0x556fbcf8da50 2020-07-14 16:29:58.220+0000: 5352: info : virObjectUnref:347 : OBJECT_UNREF: obj=0x556fbcf8d770 2020-07-14 16:29:58.220+0000: 5352: info : virEventGLibHandleDispatch:116 : EVENT_GLIB_DISPATCH_HANDLE: watch=11 events=1 cb=0x7f7b55b86c50 opaque=0x556fbcf8d770 2020-07-14 16:29:58.220+0000: 5352: error : virNetMessageDecodeLength:131 : Unable to decode message length 2020-07-14 16:29:58.220+0000: 5352: info : virKeepAliveStop:300 : RPC_KEEPALIVE_STOP: ka=0x556fbcf8e330 client=0x556fbcf8da50 2020-07-14 16:29:58.221+0000: 5352: info : virObjectRef:385 : OBJECT_REF: obj=0x556fbcf8da50 2020-07-14 16:29:58.221+0000: 5352: info : virObjectUnref:347 : OBJECT_UNREF: obj=0x556fbcf8e330 2020-07-14 16:29:58.221+0000: 5352: info : virObjectUnref:349 : OBJECT_DISPOSE: obj=0x556fbcf8e330 2020-07-14 16:29:58.221+0000: 5352: info : virKeepAliveDispose:221 : RPC_KEEPALIVE_DISPOSE: ka=0x556fbcf8e330 2020-07-14 16:29:58.221+0000: 5352: info : virObjectUnref:347 : OBJECT_UNREF: obj=0x556fbcf8da50 2020-07-14 16:29:58.221+0000: 5352: info : virObjectUnref:347 : OBJECT_UNREF: obj=0x556fbcf8da50 2020-07-14 16:29:58.221+0000: 5352: info : virObjectRef:385 : OBJECT_REF: obj=0x556fbcf8da50 2020-07-14 16:29:58.221+0000: 5352: info : virObjectUnref:347 : OBJECT_UNREF: obj=0x556fbcf8da50 2020-07-14 16:29:58.221+0000: 5352: info : virEventGLibHandleRemove:261 : EVENT_GLIB_REMOVE_HANDLE: watch=11 2020-07-14 16:29:58.221+0000: 5352: info : virObjectUnref:347 : OBJECT_UNREF: obj=0x556fbcf8d770 2020-07-14 16:29:58.221+0000: 5352: info : virNetServerCheckLimits:280 : Re-enabling services 2020-07-14 16:29:58.221+0000: 5352: info : virEventGLibHandleUpdate:194 : EVENT_GLIB_UPDATE_HANDLE: watch=2 events=1 2020-07-14 16:29:58.221+0000: 5352: info : virObjectUnref:347 : OBJECT_UNREF: obj=0x556fbcf8da50 2020-07-14 16:29:58.221+0000: 5352: info : virEventGLibHandleRemoveIdle:242 : EVENT_GLIB_REMOVE_HANDLE_IDLE: watch=11 ff=0x7f7b55b86c00 opaque=0x556fbcf8d770 2020-07-14 16:29:58.221+0000: 5352: info : virObjectUnref:347 : OBJECT_UNREF: obj=0x556fbcf8da50 2020-07-14 16:29:58.221+0000: 5352: info : virObjectUnref:349 : OBJECT_DISPOSE: obj=0x556fbcf8da50 2020-07-14 16:29:58.221+0000: 5352: info : virNetServerClientDispose:976 : RPC_SERVER_CLIENT_DISPOSE: client=0x556fbcf8da50 2020-07-14 16:29:58.221+0000: 5352: info : virEventGLibTimeoutRemove:437 : EVENT_GLIB_REMOVE_TIMEOUT: timer=1 2020-07-14 16:29:58.221+0000: 5352: info : virObjectUnref:347 : OBJECT_UNREF: obj=0x556fbcf8d770 2020-07-14 16:29:58.221+0000: 5352: info : virObjectUnref:349 : OBJECT_DISPOSE: obj=0x556fbcf8d770 2020-07-14 16:29:58.221+0000: 5352: info : virNetSocketDispose:1332 : RPC_SOCKET_DISPOSE: sock=0x556fbcf8d770 2020-07-14 16:29:58.221+0000: 5352: info : virEventGLibTimeoutRemoveIdle:417 : EVENT_GLIB_REMOVE_TIMEOUT_IDLE: timer=1 ff=(nil) opaque=0x556fbcf8da50

2 3

SELinux labels change in libvirt
by Ram Lavi 16 Jul '20

16 Jul '20

Hello all, tl;dr, can you point me to the point in the libvirt repo where it's trying to change a tap-device's SELinux label? I am trying to create a tap device with libvirt on a super-privileged container, and then use it on another, unprivileged container with libvirt. User wise, I know I need the super-privileged container to open the tap device with the user of the unprivileged one - that I already did and it's not the issue. But I have a problem when I open the tap device in the non-privileged container: the tap device currently has the spc_t label since the tun_socket inherited the selinux context from the super-privileged container who creates it. then libvirt is trying to change the SELinux labels, and since it's not privileged then it fails. But I didn't find where and how libvirt is trying to change the tap device's label. Can you point me to that specific code on libvirt? Ram Lavi Senior Software Engineer Red Hat Israel <https://www.redhat.com/> Yerushalaim Road 34, Ra'anana ralavi(a)redhat.com IM: ralavi @RedHat <https://twitter.com/redhat> Red Hat <https://www.linkedin.com/company/red-hat> Red Hat <https://www.facebook.com/RedHatInc> <https://www.redhat.com/>

2 5

Help with external snapshots as backups
by Alex Regan 14 Jul '20

14 Jul '20

Hi, I have a win10 guest on a fedora32 system and have some questions as I explore using external snapshots as a form of backup in case of a Windows failure (as in, it won't boot or is completely irrecoverable) as well as revision control (to be able to rollback changes after a failed app install, etc). The first hit on Google for external snapshots involves a RHEL7 document that talks about how it's not officially supported. The current RHEL8 docs don't include any references to snapshots. The fedora docs I've found are many years old - I'm just not sure if they're still applicable. Where can I find the current docs for fedora32? - If I've already created a live internal snapshot, can I then create an external safely? Are all changes currently being written to this internal snapshot now? - Can external snapshots be used for backup? Perhaps there are predefined steps for doing this that I can follow? This is the procedure I'm currently using. I've made a backup of the original image - can I now just continue to backup the snapshots in the eventuality of a crash, then use this original image backup and the snapshots to restore it? I suppose I would also periodically merge the snapshots back into the a single snapshot to ease the process? # virsh snapshot-create-as --domain dave-win10a win10a-state01 --diskspec vda,file=/var/lib/libvirt/images/vm_snapshots/disk-overlay.qcow2,snapshot=external --memspec file=/var/lib/libvirt/images/vm_snapshots/mem-overlay.qcow2,snapshot=external --atomic Domain snapshot win10a-state01 created # ls -lh vm_snapshots/ total 3.3G -rw------- 1 qemu qemu 196K Jul 11 12:32 disk-overlay.qcow2 -rw------- 1 root root 3.3G Jul 11 12:32 mem-overlay.qcow2 Thanks, Alex

2 1

Emulated TPM devices and snapshots of running VMs
by Milan Zamazal 09 Jul '20

09 Jul '20

Hi, I would like to clarify how to make snapshots of running VMs with emulated TPM devices. As far as I understand QEMU documentation, it's possible to make snapshots of running VMs with TPM, but it's important to retain the state of swtpm. Does libvirt assist with that in any way or is it completely user's responsibility? libvirt pauses the VM internally when making a snapshot, which should be the right moment to copy the swtpm data, but the user doesn't have control over it. Is there a way to make a copy of swtpm data that is guaranteed to be consistent with the snapshot? Thank you, Milan

2 5

Could you please help with questions about the net failover feature
by Yalan Zhang 09 Jul '20

09 Jul '20

Hi laine, I have leave some questions on IRC, but my VPN broken time after time. Please ignore the questions on IRC. In my understanding, the standby and primary hostdev interface may be in different subnet. I'm not sure whether it is correct. Could you please help to explain? Thank you in advance. For example, primary hostdev is connected to vf-pool with <pf='eth0'/>, while the standby is connected to NAT network with " forward dev='eth0'". The standby interface will get ip as 192.168.122.x, but after NAT, it will be in the same subnet of the vf. So after the VF is unplugged, the packet will still broadcast in the same subnet, and the vm will get the packet as the standby share the same mac. Right? Thank you! ------- Best Regards, Yalan Zhang IRC: yalzhang

4 7

Why wireless interface cannot be attached to a Linux host bridge?
by ryotaro kobayashi 08 Jul '20

08 Jul '20

Hello, everyone. I'm from japan and using machine translation, so I apologize if it's hard to read. I am currently trying to build a virtual environment using Ubuntu and kvm. However, I found out from the following page that the virtual machine cannot use the bridge network because I am using a wireless network. https://wiki.libvirt.org/page/Networking I am having trouble with this because my PC is using a wireless LAN. On that page it says "wireless interfaces cannot be attached to a Linux host bridge", I Can you tell me why this is so? Is it a limitation of the NIC driver for the wireless LAN? Or is it a limitation of libvirt? Best regards.

6 9