May 2019 - Users - libvirt List Archives

[libvirt-users] bridge / ubuntu / no arp reply
by François Chenais 15 Oct '26

15 Oct '26

Hello I'm trying to setup a bridged guest on an ubuntu 13.10 but it doesn't work. (Everything is ok with NAT) Network sniffing shows that arp replies don't come back to the guest. Test 1 ------ Guest : ping host_bridge_ip (ok) Test 2 ------ Guest: ping other_lan_host (KO) other_lan_host - receives arp who-is request - sends arp reply - arp -a shows the guest macaddr => Guest doesn't receive reply Test 3 ------ other_lan_host ping the Guest (KO) - arp -a shows "incomplete" addr - Guest receives nothing On Host ------- network tcpdump on bridge or vnet interfaces shows request but no reply ... Thanks in advance for help or ideas François

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[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

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[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

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[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

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[libvirt-users] Using qemu active blockcommit results in 'Permission denied' error
by Marcus Hoffmann 13 Jun '19

13 Jun '19

Hello all, I tried following this guide: https://wiki.libvirt.org/page/Live-disk-backup-with-active-blockcommit Unfortunately when I try to do the final virsh blockcommit step I always get the following error: error: internal error: unable to execute QEMU command 'block-commit': Could not reopen file: Permission denied I checked directory und image file permissions, app-armor profiles (set to complain mode for now.) and libvirt logs but nothing there gives me any hints what might be going wrong. This is on a debian buster system, using libvirtd (libvirt) 5.0.0 qemu 3.1+dfsg-7 I would appreciate any hints on how to proceed/get more debug info on this. Thanks! Marcus

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[libvirt-users] Easy solution for custom firewall rules- is it possible?
by Joshua Kramer 03 Jun '19

03 Jun '19

Hello All- I've looked in several places and haven't found an answer to this question: is it possible to have libvirt add custom rules to iptables for virtual network interfaces? I took a look at the "Firewall and Network Filtering in Libvirt" page and it seems overly complicated for what I want to do. Given an interface virbr2 and its network 192.168.4.0/24, libvirt installs the following rules in iptables. Essentially, these rules will drop any packets for the interface virbr2 where the source or destination is not on the 192.168.4.0/24 network. -P FORWARD ACCEPT -A FORWARD -d 192.168.4.0/24 -o virbr2 -j ACCEPT -A FORWARD -s 192.168.4.0/24 -i virbr2 -j ACCEPT -A FORWARD -i virbr2 -o virbr2 -j ACCEPT -A FORWARD -o virbr2 -j REJECT --reject-with icmp-port-unreachable -A FORWARD -i virbr2 -j REJECT --reject-with icmp-port-unreachable I have a VPN server on the 4/24 network- and it hands out addresses in the 8/24 network. So I would like libvirt to also create the following rules in iptables: -A FORWARD -d 192.168.8.0/24 -o virbr2 -j ACCEPT -A FORWARD -s 192.168.8.0/24 -i virbr2 -j ACCEPT I've tried creating direct rules in firewalld for the FORWARD_direct chain. Firewalld happily creates those rules, but they are never reached, because they fall AFTER the libvirt rules. I've also tried creating an IP address on the virbr2 interface in the 8/24 network, but that doesn't work either. How can I get this done? Thanks!! -JK

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[libvirt-users] logging of domains
by Lentes, Bernd 30 May '19

30 May '19

Hi, recently i had some domains stopped without any obvious reason for me. Unfortunately i didn't find the cause. I'd like to log information about the domains that i have more information the next time this will happen. In /etc/libvirt/libvirtd.conf i have: log_level = 3 log_outputs="3:file:/var/log/libvirt/libvirtd.log" which creates enormous log files, but with logrotate and xz i can manage that. But i think this is just related to libvirtd. The logs for the domains under /var/log/libvirt/qemu are poor and very small, nearly no information. Is there a way to be more verbose with the domains so that i may find helpful information in these logs when the domains stop for the next time ? Thanks. Bernd -- Bernd Lentes Systemadministration Institut für Entwicklungsgenetik Gebäude 35.34 - Raum 208 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/idg wer Fehler macht kann etwas lernen wer nichts macht kann auch nichts lernen Helmholtz Zentrum Muenchen Deutsches Forschungszentrum fuer Gesundheit und Umwelt (GmbH) Ingolstaedter Landstr. 1 85764 Neuherberg www.helmholtz-muenchen.de Stellv. Aufsichtsratsvorsitzender: MinDirig. Dr. Manfred Wolter Geschaeftsfuehrung: Prof. Dr. med. Dr. h.c. Matthias Tschoep, Heinrich Bassler, Kerstin Guenther Registergericht: Amtsgericht Muenchen HRB 6466 USt-IdNr: DE 129521671

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[libvirt-users] libvirt blkiotune mechanism
by Maksym Isaiev 30 May '19

30 May '19

Hello! We are using oVirt in our infrastructure, which uses libvirt as backend. Last time we needed to activate storage QoS aka libvirt blkiotune parameters. So some questions appeared about how libvirt limitation mechanism works: 1. What happened to overlimit storage traffic in small time period after we apply blkiotune parameters on high loaded virtual machine on fly: a) All over-limit traffic pulled into some queue, where all disk transactions can be successfully finished with QoS throughput? b) All over-limitation data dropped and opened transactions state became failed? c) All active transactions finishes on speed beyond blkiotune parameters limit, but all new transactions immediately are limited based on configured limits? Thanks in advance!

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[libvirt-users] Snapshot of single block device
by jarek 29 May '19

29 May '19

Hello! I have a guest with one qcow2 disk image (vda) and one physical partition (sda) from host. When I'm trying to get snapshot with: virsh snapshot-create-as ..... It fails with message: error: unsupported configuration: source for disk 'sda' is not a regular file; refusing to generate external snapshot name I understand, that it is not possible to make a snapshot of physical device, but it is enough for me to take snapshot of vda. How to force virsh to ignore sda ? best regards Jarek

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[libvirt-users] [Libvirt failed to claim Virtual Functions on hostdev network after VM reboot]
by Fuzail Ahmad 29 May '19

29 May '19

Problem Statement: Libvirt failed to claim Virtual Functions on hostdev network after VM reboot. Version-Release number of selected component (if applicable): libvirtd (libvirt) 2.0.0 kernel-4.1.12-112.16.4.el7uek.x86_64 Reproducible: Not always Description: I am doing a reboot of Virtual machines and sometimes one of the VM does not start and fail with the following error In total I have spun 3 VMs out of which 2 gets started and 1 of them fail with the below error. [root@sriov2 ~]# virsh start VM3 error: Failed to attach interface error: internal error: network 'hostnet' requires exclusive access to interfaces, but none are available [root@sriov2 ~]# virsh net-dumpxml hostnet <network connections='2'> <name>hostnet</name> <uuid>c1fb4ead-21b8-4d69-8ad9-669c55b3dfc7</uuid> <forward mode='hostdev' managed='yes'> <address type='pci' domain='0x0000' bus='0x0f' slot='0x10' function='0x0'/> <address type='pci' domain='0x0000' bus='0x0f' slot='0x10' function='0x2'/> </forward> </network> However, "ip link show" command shows 8 VFs in total. # ip link show ens2 ens2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 9000 qdisc mq state UP mode DEFAULT qlen 1000 link/ether 00:0a:f7:d5:a7:50 brd ff:ff:ff:ff:ff:ff vf 0 MAC 52:54:00:6d:7c:a0, spoof checking off, link-state auto vf 1 MAC 52:54:00:44:c9:b6, spoof checking off, link-state auto vf 2 MAC 52:54:00:30:7a:86, spoof checking off, link-state auto vf 3 MAC c6:9a:1b:82:90:ea, spoof checking off, link-state auto vf 4 MAC 46:db:e2:33:c7:a4, spoof checking off, link-state auto vf 5 MAC 76:65:e1:f7:82:78, spoof checking off, link-state auto vf 6 MAC 8e:a0:8b:e5:1a:66, spoof checking off, link-state auto vf 7 MAC ba:f4:83:19:80:bf, spoof checking off, link-state auto # Please, letme know if I need to attach any additional information. Regards Fuzail

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[libvirt-users] libvirtd not starting
by Lothar Schilling 22 May '19

22 May '19

Hi everybody, I've set up an new CentOS 7.6.1810 server. Then, via yum I installed qemu-kvm libvirt libvirt-python libguestfs-tools virt-install. There were no problems. But when I try to systemctl start libvirtd I get the following message: "libvirtd: process 472: arguments to dbus_message_iter_append_basic() were incorrect, assertion "_dbus_check_is_valid_utf8 (*string_p)" failed in file ../../dbus/dbus-message.c line 2754." Starting libvirtd manually just by issuing the command "libvirtd" without any further arguments is working, though. I do not have the slightest idea what is going on, especially as I didn't change anything about the config files. Any help would be appreciated, thank you Lothar Schilling

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[libvirt-users] VM bootup got failed with systemd/dbus error messages
by PRIYANKA M A 22 May '19

22 May '19

We are having one server machine (ubuntu 16.04 OS) with 10 VMs. When the server is rebooted, some VMs got failed to boot with systemd/dbus error messages. Rebooting the affected VMs resolves this issue. Jan 30 20:40:02 VM systemd[1]: Failed to subscribe to NameOwnerChanged signal for 'org.freedesktop.DisplayManager': Connection timed out Jan 30 20:40:02 VM systemd[1]: Failed to subscribe to NameOwnerChanged signal for 'org.freedesktop.NetworkManager': Connection timed out Jan 30 20:40:02 VM systemd[1]: Failed to subscribe to NameOwnerChanged signal for 'org.freedesktop.login1': Connection timed out Jan 30 20:40:02 VM systemd[1]: Failed to subscribe to NameOwnerChanged signal for 'org.freedesktop.Accounts': Connection timed out Jan 30 20:40:02 VM systemd[1]: Failed to subscribe to NameOwnerChanged signal for 'org.freedesktop.Avahi': Connection timed out Jan 30 20:40:02 VM systemd[1]: Failed to subscribe to NameOwnerChanged signal for 'org.freedesktop.ModemManager1': Connection timed out Jan 30 20:40:02 VM systemd[1]: Failed to subscribe to activation signal: Connection timed out Jan 30 20:40:02 VM systemd[1]: Failed to register name: Connection timed out Jan 30 20:40:02 VM systemd[1]: Failed to set up API bus: Connection timed out an 30 20:40:32 VM dbus[1009]: [system] Failed to activate service 'org.freedesktop.systemd1': timed out Jan 30 20:40:32 VM systemd-logind[998]: Failed to enable subscription: Failed to activate service 'org.freedesktop.systemd1': timed out Jan 30 20:40:32 VM systemd-logind[998]: Failed to fully start up daemon: Connection timed out Host machine specifications:- OS : Ubuntu 16.04 Kernel : 4.15.0-47-generic CPUs : 48 ( 2*12*2) RAM : 64G VM specifications:- OS : Ubuntu 16.04 Kernel : 4.13.16 CPUs : 8 RAM : 4G Attached the full log file. Kindly help us to resolve this issue with a permanent fix. *With Best Regards,* M A PRIYANKA VVDN Technologies Pvt Ltd *Cell : * +91 8489574081 | *Skype :* priyankamathavan27 -- _Disclaimer: _© 2019 VVDN Technologies Pvt. Ltd. This e-mail contains PRIVILEGED AND CONFIDENTIAL INFORMATION intended solely for the use of the addressee(s). If you are not the intended recipient, please notify the sender by e-mail and delete the original message. Further, you are not to copy, disclose, or distribute this e-mail or its contents to any other person and any such actions are unlawful.__

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[libvirt-users] GVT-g - suboptimal user experience
by Alex Ivanov 20 May '19

20 May '19

Hi. In the current state of gvt-g the user experience is suboptimal. So my question is what are the ETAs for following features: 1. Accelerated virt-manager console using gvt-g device 2. Custom resolutions or dynamic resolution 3. UEFI VMs support (Windows guest) Thanks.

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[libvirt-users] virtio-user intarfece
by Avi Cohen 19 May '19

19 May '19

Hello all i have multiple workload containers connected to my DPDK-app. I have another special container - which all packets are mirrored to it. Is it possible for zero-copy reason - that all virtio interfaces shared memory between my DPDK-app and workload containers - can be accessed by this special container ? it means that for every workload container X this is a shared memory between the:

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Re: [libvirt-users] [libvirt] surprising <backingStore type='file'> setting in domain.xml
by Thomas Stein 17 May '19

17 May '19

(switched to libvirt-users as it seems to be more appropriate) On 2019-05-16 23:02, Eric Blake wrote: > On 5/16/19 10:20 AM, Thomas Stein wrote: >> Hello all. >> >> My currently used versions: libvirt-5.2.0 and qemu-4.0.0. >> >> Here is my problem. I'm struggeling since a few weeks with a strange >> behaviour by either qemu or libvirt. After a reboot of >> the hardware node the $domain.xml contains suddenly a backingStore >> setting which was not there before reboot. >> Something like that: >> >> <devices> >> <emulator>/usr/bin/qemu-system-x86_64</emulator> >> <disk type='file' device='disk'> >> <driver name='qemu' type='qcow2'/> >> <source >> file='/var/lib/libvirt/shinymail/shinymail_weekly.qcow2-2019-05-15'/> >> <backingStore type='file'> >> <format type='qcow2'/> >> <source file='/var/lib/libvirt/images/shinymail.qcow2'/> > > Yes, this matches: > >> </backingStore> >> <target dev='vda' bus='virtio'/> >> <address type='pci' domain='0x0000' bus='0x00' slot='0x07' >> function='0x0'/> >> </disk> >> ... >> >> This obviousely happens after a backup has been running. The Backup >> Script looks like this: >> >> <snip> >> virsh snapshot-create-as --domain shinymail weekly --diskspec >> vda,file=/var/lib/libvirt/shinymail/shinymail_weekly.qcow2-$(date >> +%Y-%m-%d) --disk-only --atomic --no-metadata > > the effects of this command. > > Ultimately, I'm TRYING to get my new 'virsh domain-backup' command > integrated into the next libvirt release, which has the advantage of > performing a backup WITHOUT having to modify the <domain> XML. But > until > that happens, any time you use 'virsh snapshot-create-as' as part of a > sequence for performing backups, you ARE modifying the <domain> XML, > and > if you want to revert to the external backup, or if... Cool. Will it be in 5.4.0 already? >> >> cp ... >> >> virsh blockcommit shinymail vda --active --verbose --pivot >> <snip> > > ...blockcommit fails for whatever reason to undo the effects of > 'snapshot-create-as' in creating a temporary overlay, then yes, you do > have to worry about the temporary overlay being in the way, where > you'll > have to manually edit the <domain> definition to match the actual disk > layouts you really want. So you're saying blockcommit fails me somehow? What i'm asking myself is, why does this problem suddenly appear. It worked literally for years this way. thanks for your answer Eric. cheers t. >> >> So after that "dmblklist shinymail" does show the right source file >> but >> after a reboot it tries to use the weekly snapshot >> again which leads to filesystem errors. >> >> Someone has an idea what could cause such a behaviour? >>

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[libvirt-users] surprising <backingStore type='file'> setting in domain.xml
by Thomas Stein 16 May '19

16 May '19

Hello all. My currently used versions: libvirt-5.2.0 and qemu-4.0.0. Here is my problem. I'm struggeling since a few weeks with a strange behaviour by either qemu or libvirt. After a reboot of the hardware node the $domain.xml contains suddenly a backingStore setting which was not there before reboot. Something like that: <devices> <emulator>/usr/bin/qemu-system-x86_64</emulator> <disk type='file' device='disk'> <driver name='qemu' type='qcow2'/> <source file='/var/lib/libvirt/shinymail/shinymail_weekly.qcow2-2019-05-15'/> <backingStore type='file'> <format type='qcow2'/> <source file='/var/lib/libvirt/images/shinymail.qcow2'/> </backingStore> <target dev='vda' bus='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x07' function='0x0'/> </disk> ... This obviousely happens after a backup has been running. The Backup Script looks like this: <snip> virsh snapshot-create-as --domain shinymail weekly --diskspec vda,file=/var/lib/libvirt/shinymail/shinymail_weekly.qcow2-$(date +%Y-%m-%d) --disk-only --atomic --no-metadata cp ... virsh blockcommit shinymail vda --active --verbose --pivot <snip> So after that "dmblklist shinymail" does show the right source file but after a reboot it tries to use the weekly snapshot again which leads to filesystem errors. Someone has an idea what could cause such a behaviour? cheers t. -- libvir-list mailing list libvir-list(a)redhat.com https://www.redhat.com/mailman/listinfo/libvir-list

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[libvirt-users] domain still running although snapshot-file is deleted !?!
by Lentes, Bernd 15 May '19

15 May '19

Hi, i have a strange situation: A domain is still running where domblklist points to a snapshot file and also dumpxml says the current drive is that snapshot file. But the file has been deleted hours ago. And the domain is still running. I can login via ssh, the database and the webserver are still running, domain is performant. How can that be ? Also lsof shows that the file is deleted: qemu-syst 27007 qemu 15ur REG 254,14 335609856 183599 /mnt/snap/sim.sn (deleted) qemu-syst 27007 qemu 16ur REG 254,14 335609856 183599 /mnt/snap/sim.sn (deleted) qemu-syst 27007 27288 qemu 15ur REG 254,14 335609856 183599 /mnt/snap/sim.sn (deleted) qemu-syst 27007 27288 qemu 16ur REG 254,14 335609856 183599 /mnt/snap/sim.sn (deleted) CPU\x200/ 27007 27308 qemu 15ur REG 254,14 335609856 183599 /mnt/snap/sim.sn (deleted) CPU\x200/ 27007 27308 qemu 16ur REG 254,14 335609856 183599 /mnt/snap/sim.sn (deleted) CPU\x201/ 27007 27309 qemu 15ur REG 254,14 335609856 183599 /mnt/snap/sim.sn (deleted) CPU\x201/ 27007 27309 qemu 16ur REG 254,14 335609856 183599 /mnt/snap/sim.sn (deleted) vnc_worke 27007 27321 qemu 15ur REG 254,14 335609856 183599 /mnt/snap/sim.sn (deleted) vnc_worke 27007 27321 qemu 16ur REG 254,14 335609856 183599 /mnt/snap/sim.sn (deleted) Bernd -- Bernd Lentes Systemadministration Institut für Entwicklungsgenetik Gebäude 35.34 - Raum 208 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/idg wer Fehler macht kann etwas lernen wer nichts macht kann auch nichts lernen Helmholtz Zentrum Muenchen Deutsches Forschungszentrum fuer Gesundheit und Umwelt (GmbH) Ingolstaedter Landstr. 1 85764 Neuherberg www.helmholtz-muenchen.de Stellv. Aufsichtsratsvorsitzender: MinDirig. Dr. Manfred Wolter Geschaeftsfuehrung: Prof. Dr. med. Dr. h.c. Matthias Tschoep, Heinrich Bassler, Kerstin Guenther Registergericht: Amtsgericht Muenchen HRB 6466 USt-IdNr: DE 129521671

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[libvirt-users] domains paused without any obvious reason
by Lentes, Bernd 14 May '19

14 May '19

Hi, i have a two node HA-Cluster with several domains as resources. Currently it's running in test mode. Some domains (all on the same host) stopped running, virsh list shows them as "paused". All stopped at the same time (11th of may, 7:00 am), my monitoring system began to yell. I don't have any clue why this happened. virsh domblkerror says for all the domains (5) "no space". The days before the domains were running fine and i know that all disks inside the domain should have enough space. Also the host is not running out of space. The logs don't say anything sensefully, unfortunately i didn't have a log for the libvirtd daemon, i just configured that now. The domains are stopped each day by cron at 10:30 pm for a short moment, a snapshot is taken, domains are started again, the backing file is copied to a CIFS server and if that is finished the snapshot is blockcommited into the backing file. That's working fine already for several days. This cronjob creates a log and it's looking fine. The domains reside in naked Logical Volumes, the respective Volume Group has enough space. Bernd -- Bernd Lentes Systemadministration Institut für Entwicklungsgenetik Gebäude 35.34 - Raum 208 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/idg wer Fehler macht kann etwas lernen wer nichts macht kann auch nichts lernen Helmholtz Zentrum Muenchen Deutsches Forschungszentrum fuer Gesundheit und Umwelt (GmbH) Ingolstaedter Landstr. 1 85764 Neuherberg www.helmholtz-muenchen.de Stellv. Aufsichtsratsvorsitzender: MinDirig. Dr. Manfred Wolter Geschaeftsfuehrung: Prof. Dr. med. Dr. h.c. Matthias Tschoep, Heinrich Bassler, Kerstin Guenther Registergericht: Amtsgericht Muenchen HRB 6466 USt-IdNr: DE 129521671

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[libvirt-users] VM display is blank when open (but Gnome Boxes thumbnails ok)
by Michel Rozpendowski 13 May '19

13 May '19

Hi, I also posted this question on the IRC #virt channel but have not received any reaction at the moment of posting this message to the mailing list. Since I last turned off my laptop (Dell XPS-15-9570 running Ubuntu 19.04) on Friday 10 May (I had to do it by long power press by the way), I am no longer able to get the display of my VMs: I am getting a black screen, even though I can see it running in the thumbnail of Gnome Boxes. You can see the described behaviour on the following video capture: https://youtu.be/Lv67g0foyzc. Troubleshooting Log from Gnome Boxes is available here: https://pastebin.com/9eWGYsJV. It was working all properly on Friday before I turn off my laptop. Any clue what could be wrong and how I could solve this issue (I digged the Internet for 2 hours without success)? Thanks in advance for your help! Kind regards, Michel

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[libvirt-users] Cannot get interface MTU - qemu quest fails to start off OpenVswitch
by lejeczek 13 May '19

13 May '19

hi guys I have a qemu guest and openvswitch bridge and the guest fails to start: $ virsh start work8 error: Failed to start domain work8-vm-win2016 error: Cannot get interface MTU on 'ovsbr0': No such device LXC guest which uses the same source network starts just fine. I'm on Centos 7 with openvswitch-2.9.0-3.el7.x86_64 from centos-openstack-pike repo and libvirt-4.5.0-10.el7_6.7.x86_64. Would anybody care to suggest a possible reson(s) causing the failure? many thanks, L.

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[libvirt-users] Running libvirtd out of source directory connection reset error
by Peter P. 10 May '19

10 May '19

Hi all, I'm getting started with hacking around with libvirt and am trying to familiarize myself with launching and running an instance of libvirtd I built from source on Centos 7.6. Following the instructions from https://libvirt.org/compiling.html to launch my built versions of libvirtd and virsh, I get the following error with no other context when trying to start a domain using "virsh start mydomain": error: Cannot recv data: Connection reset by peer Despite this error, I am able to run commands list virsh list. Are there additional parameters needed to launch libvirtd or additional services I need to start up alongside it? Thanks, Peter

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Re: [libvirt-users] disable libvirt-nwfilter
by Michal Privoznik 07 May '19

07 May '19

[Please keep the list CC-ed as it may help somebody from future when searching for solution to the same problem] On 5/6/19 6:08 PM, nakata(a)geekpit.org wrote: > Am 2019-05-06 16:26, schrieb Michal Privoznik: >> On 5/6/19 3:44 PM, nakata(a)geekpit.org wrote: >>> Hi, >>> >>> i want to disable the nwfilter functionality of libvirt. >>> It's surely nice for some people, nevertheless i don't want libvirt >>> to alter any netfilter rules, neither i want the according >>> functionality even available. >> >> It's not only NWFilter that will inject firewall rules. Depending on >> configuration it might also be the default network. >> >>> I know about nwfilter-undefine, but what i'm looking for is an option >>> to globally disable this functionality at all. Some config flag or >>> similar. >>> How can i achieve that? >> >> Unless you have a domain <interface/> defined so that it uses a >> nwfilter then no firwall rules are added by nwfilter code. >> >> If you still want to remove nwfilter module then just uninstall it, >> e.g. via: >> >> dnf remove libvirt-daemon-driver-nwfilter libvirt-daemon-config-nwfilter >> >> Michal > > Hi, > > me again. > Another question libvirt is adding chains. Where do i disable these: > > chains are LIBVIRT-{FWO,FWX,FWI, INP, OUT} > > These are absolutely and explicit unwanted. > Adding new rich features for folks is a fine thing, but i need an opt out. > Please, how do i get rid of it? As I've said, there are two sources which cause libvirt to insert FW rules. By uninstalling nwfilter module you've eliminated one. But since you're still able to run the domain this step was useless because your domain doesn't have nwfilter configured for any of its <interface/>-s and thus nwfilter module did nothing but sit there. The other module that is inserting FW rules is network module. Currently, when libvirtd is starting it reads all the configs of defined networks. If a NATed network is found then it creates those LIBVIRT-* chains and when the network is started then all the rules will be placed into those chains to not contaminate config set by sysadmin. There is patch to postpone creating the chains unitl network actually is starting: https://www.redhat.com/archives/libvir-list/2019-April/msg01547.html So your options here are: a) undefine all NATed networks (typically there's 'default' network) b) uninstall network module (but this will render all domains using <interface type='network'/> unable to start). As an extension to a) you can have a network with <forward mode='open'/> which preserves all the advantages of having a libvirt network but does not install any FW rules. Of course, any comments to aforementioned patch are welcome too. Michal

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[libvirt-users] Autodetecting backing file properties when using vol-create-as
by Gionatan Danti 06 May '19

06 May '19

Hi all, experimenting with vol-create-as, I think it should autodetect some data - filesize and backing file format, specifically. However, the current implementation require us to specify both filesize and backing file format. Considering that qemu-img already autodetects these data, there are any reason for the lack of autodetect by libvirt? Should I open a bugzilla issue? Below you can find a practical example of what I mean. System is CentOS Linux release 7.6.1810 (Core) with libvirt-4.5.0-10.el7_6.4.x86_64 Please let me know if I am missing something. Thanks. # create base file [root@singularity images]# qemu-img create base.qcow2 8G -f qcow2 Formatting 'base.qcow2', fmt=qcow2 size=8589934592 cluster_size=65536 lazy_refcounts=off refcount_bits=16 [root@singularity images]# qemu-img info base.qcow2 image: base.qcow2 file format: qcow2 virtual size: 8.0G (8589934592 bytes) disk size: 17K cluster_size: 65536 Format specific information: compat: 1.1 lazy refcounts: false refcount bits: 16 corrupt: false # create overlay1.qcow2 via qemu-img; note how backing file format is autodetected ("-f qcow2" regards the overlay file itself) [root@singularity images]# qemu-img create -b /var/lib/libvirt/images/base.qcow2 overlay1.qcow2 -f qcow2 Formatting 'overlay1.qcow2', fmt=qcow2 size=8589934592 backing_file=/var/lib/libvirt/images/base.qcow2 cluster_size=65536 lazy_refcounts=off refcount_bits=16 [root@singularity images]# qemu-img info overlay1.qcow2 image: overlay1.qcow2 file format: qcow2 virtual size: 8.0G (8589934592 bytes) disk size: 17K cluster_size: 65536 backing file: /var/lib/libvirt/images/base.qcow2 Format specific information: compat: 1.1 lazy refcounts: false refcount bits: 16 corrupt: false # try the same with virsh vol-create-as; note how you must specify filesize and the backing file format is *wrong* (leading to an unusable overlay disk) [root@singularity images]# virsh vol-create-as default overlay2.qcow2 8G --format qcow2 --backing-vol /var/lib/libvirt/images/base.qcow2 Vol overlay2.qcow2 created [root@singularity images]# qemu-img info overlay2.qcow2 image: overlay2.qcow2 file format: qcow2 virtual size: 8.0G (8589934592 bytes) disk size: 17K cluster_size: 65536 backing file: /var/lib/libvirt/images/base.qcow2 backing file format: raw Format specific information: compat: 0.10 refcount bits: 16 -- 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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[libvirt-users] disable libvirt-nwfilter
by nakata＠geekpit.org 06 May '19

06 May '19

Hi, i want to disable the nwfilter functionality of libvirt. It's surely nice for some people, nevertheless i don't want libvirt to alter any netfilter rules, neither i want the according functionality even available. I know about nwfilter-undefine, but what i'm looking for is an option to globally disable this functionality at all. Some config flag or similar. How can i achieve that? greetings

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[libvirt-users] VM: Unable to enable scatter-gather / tx-checksumming / tcp-segmentation offload
by Harsh Gondaliya 06 May '19

06 May '19

In my Linux VM, I am unable to change scatter-gather / tx-checksumming / TCP-segmentation offload features by ethtool command. I am using virtio nic with vhostuser port backend. It shows me an error: Cannot change tx-checksumming Cannot change scatter-gather Cannot change tcp-segmentation offload Could not change any device features Ony running command ethtool -k ens3, I get the following: [image: image.png] If there is something that needs to be changed in the domain XML itself then please guide me what changes to do?

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