- Users - libvirt List Archives

[libvirt-users] How to insert a dummy NIC
by wferi＠niif.hu 11 Mar '19

11 Mar '19

Hi, I have to host (with KVM) an appliance which does not use its second and third NIC. They have to be present in the guest, but they'd better stay totally disconnected from anything in the host. "Second" and "third" apparently means bus order. Let's consider virtio devices only. I think the best technical solution is adding -device virtio-net-pci,addr=0x3 and similar options to the KVM command line, without any corresponding -netdev options (better ideas welcome). QEMU emits "Warning: nic virtio-net-pci.2 has no peer" messages, but that's expected. I can even do this much using the <qemu:commandline> element, but libvirt assigns the 0x3 address to other virtio devices, leading to collision. Is there a way to "reserve" a bus address for such manually added devices without assigning explicit addresses to all other devices in the configuration? Things I also tried (and found inadequate): * Using "generic ethernet connection" for the dummy NICs. Close, but requires extra permissions for accessing /dev/net/tun, and technically feels a little inferior to using a peerless network device like above. * TCP tunnel server. Even more inferior, does not require extra permissions but leaves even looser ends (listening sockets). Also, the RelaxNG grammal does not let me specify a model for this interface type, so maintaining bus order with respect to the virtio interfaces is impossible. A grammar bug? * Using a dummy VLAN in the bridge. This is what I temporarily settled for, but this requires global agreement and still technically inferior, so I'd like to move away. * A <network> without forwarding. Still inferior, and also requires configuration sharing across the host cluster. -- Thanks, Feri

2 2

[libvirt-users] Obtaining the PID of a domain's QEMU process from C
by Shawn Anastasio 11 Mar '19

11 Mar '19

Hello all, I'm currently writing a C program that uses the libvirt API and I need a way to obtain the pid of a given domain's QEMU process. Specifically, I'm writing an ivshmem server that uses SO_PEERCRED to get the pid of clients that connect to it, and I would like to use that pid to look up the domain in libvirt to determine the proper domain ID to return to the client. As far as I can tell, libvirt doesn't expose this information in an easy to access manner. Of course it is possible to call `ps` and grep for the information I'm looking for, but I was hoping for a cleaner solution. If anybody knows how to do this, advice would be greatly appreciated. Thanks in advance, Shawn

7 10

[libvirt-users] Development of Libvirt PHP
by Maximilian Schieder 08 Mar '19

08 Mar '19

Hey, I want to ask if LibVirt PHP will be develop further or if it is deprecated. Kind regards, Maxi

4 3

[libvirt-users] why attach-disk can't be effective when the guest is booting
by Jianan Gao 07 Mar '19

07 Mar '19

Hi, When i use "virsh attach-device rhel disk.xml" when the guest is booting,then i can't find the disk in the guest after booting.But i can find it by "virsh domblklist rhel",and when i want to detach it from the guest and use "virsh detach-disk rhel vdb", i still can find the disk by "virsh domblklist rhel" The disk.xml is like: <disk type="file" device="disk"> <driver name='qemu' type='raw' cache='none'/> <source file="/var/lib/libvirt/images/foo.img"/> <target dev="vdb" bus="virtio"/> </disk> Libvirt-release is 5.0.0.4 and the qemu-kvm release is 3.1.0 So i want to know why it failed to attach-disk when booting,and why we design in this way.Maybe it's better to return failure if we can't use it like this.

2 1

[libvirt-users] virsh hangs when backup jobs run on the kvm host
by Zhan Adlun 07 Mar '19

07 Mar '19

Hi, Has anyone met the same problem that virsh hangs when there are some backup jobs running on the kvm host? I use dirty bitmap supported by qemu to do backups every 6 minitues. About a few hours later, I ran 'virsh list', It hung. Then I stopped the backup jobs ，nothing was getting better. I had checked the libvirt logs ，but found nothing useful . Maybe the high I/O caused the problem? or there are connection number limits when using virsh, because I use virsh to check the backup jobs are still running every 10 seconds? My os version is ' Ubuntu 12.04 LTS Release: 12.04 Codename: precise,Linux version 4.1.0-generic (gcc version 4.6.3 (Ubuntu/Linaro 4.6.3-1ubuntu5) ) #1 SMP Wed Nov 9 02:04:23 CST 2016'. KVM version is 'QEMU emulator version 2.7.1(Debian 1:2.7+dfsg-3)'. Hoping for you reply. Thanks!

3 3

[libvirt-users] How do I close a console connection?
by Lars Kellogg-Stedman 05 Mar '19

05 Mar '19

I'm working on (re-) implementing serial console support in virtualbmc [1], and one of the issues I'm hitting right now is that after establishing a console connection via... self._stream = self._conn.newStream(libvirt.VIR_STREAM_NONBLOCK) self._domain.openConsole(None, self._stream, 0) ...I can't figure out how to close the console. Subsequent calls to openConsole fail because "a console connection is already open". I thought maybe I should close the stream, but that doesn't appear to be possible (there is a finish method, but it just tells me that "this function is not supported by the connection driver"). [1]: https://github.com/openstack/virtualbmc Cheers, -- Lars Kellogg-Stedman <lars(a)redhat.com> | larsks @ {irc,twitter,github} http://blog.oddbit.com/ |

2 1

[libvirt-users] libvirt 5.0.0 - LXC container still in "virsh list" output after shutdown
by mxs kolo 25 Feb '19

25 Feb '19

Hello. Centos 7.6 with libvirt build from base "virt" repository: libvirt-daemon-driver-lxc-5.0.0-1.el7.x86_64 libvirt-client-5.0.0-1.el7.x86_64 libvirt-daemon-5.0.0-1.el7.x86_64 libvirt-daemon-driver-network-5.0.0-1.el7.x86_64 libvirt-libs-5.0.0-1.el7.x86_64 + systemd-219-62.el7_6.2.x86_64 Now lxc containers with type='direct' can be started, but can't be stopped :) Before shutdown. # virsh list --all Id Name State ------------------------------------------ 16312 test.lxc running # machinectl | grep test lxc-16312-test.lxc container libvirt-lxc # pstree -apA 16312 libvirt_lxc,16312 --name test.lxc --console 42 --security=none --handshake 45 --veth macvlan0 |-systemd,16315 | |-agetty,16690 --noclear --keep-baud console 115200 38400 9600 vt220 | |-dbus-daemon,16659 --system --address=systemd: --nofork --nopidfile --systemd-activation | |-rsyslogd,17614 -n | | |-{rsyslogd},17616 | | `-{rsyslogd},17626 | |-sshd,17613 -D | |-systemd-journal,16613 | `-systemd-logind,16657 `-{libvirt_lxc},16319 Shutdown. # virsh shutdown 16312 Domain 16312 is being shutdown # echo $? 0 After. In list output still present: # virsh list --all Id Name State ------------------------------------------ 16312 test.lxc running # machinectl | grep test | wc -l 0 No main process: # ps axuwwf | grep libvirt_lxc | grep test | wc -l 0 LXC realy stopped, but only virsh still show it in list Cgroups "blkio, cpuacct, memory, cpu, cpu,cpuacct, devices, hugetlb, pids" deleted. But another cgroups still present in fs: drwxr-xr-x 2 root root 0 Jan 21 13:07 /sys/fs/cgroup/cpuset/machine.slice/machine-lxc\x2d16312\x2dtest.lxc.scope drwxr-xr-x 2 root root 0 Jan 21 13:07 /sys/fs/cgroup/freezer/machine.slice/machine-lxc\x2d16312\x2dtest.lxc.scope drwxr-xr-x 2 root root 0 Jan 21 13:07 /sys/fs/cgroup/net_cls/machine.slice/machine-lxc\x2d16312\x2dtest.lxc.scope drwxr-xr-x 2 root root 0 Jan 21 13:07 /sys/fs/cgroup/net_cls,net_prio/machine.slice/machine-lxc\x2d16312\x2dtest.lxc.scope drwxr-xr-x 2 root root 0 Jan 21 13:07 /sys/fs/cgroup/net_prio/machine.slice/machine-lxc\x2d16312\x2dtest.lxc.scope drwxr-xr-x 2 root root 0 Jan 21 13:07 /sys/fs/cgroup/perf_event/machine.slice/machine-lxc\x2d16312\x2dtest.lxc.scope Restarted libvirtd temporary place container in correct state: # systemctl restart libvirtd # virsh list --all | grep test - test.lxc shut off libvirt 4.5.0 and 4.10.0 perform correct LXC shutdown. b.r. Maxim Kozin

2 3

[libvirt-users] virsh confirmed edits do not persist
by Josh Mcneil 21 Feb '19

21 Feb '19

This may be user error, I am new to libvirt. I am using libvirt 5.0.0. I have created a VM (win10) in the system URI using virt-manager. I stopped the VM to edit it. I set my LIBVIRT_DEFAULT_URI="qemu:///system" and am able to read the domain configuration with `EDITOR=nano virsh edit win10`. When I save (ctrl+o) and exit (ctrl+x) I see the message "Domain win10 XML configuration edited." as expected. However, when I run the edit command again the changes do not appear to have persisted. I have tried starting and stopping the VM. I read that I may need to define the domain with virsh so I did that. None of these things seem to work. I would appreciate it if someone could help me solve this issue in order to be able to modify domains from virsh! Thanks in advance for any help! Josh

2 3

[libvirt-users] HELP!
by Shashwat shagun 15 Feb '19

15 Feb '19

I'm getting this error (below) [root@localhost test]# ./test virError(Code=6, Domain=20, Message='invalid connection pointer in virConnectListAllDomains') 0 running domains: when running this program :- (below) package main import ( "fmt" libvirt "github.com/libvirt/libvirt-go" ) type DomService struct { Conn *libvirt.Connect } func (d *DomService) Connect() error { var err error d.Conn, err = libvirt.NewConnect("qemu:///system") if err != nil { fmt.Println(err) } defer d.Conn.Close() return nil } func (d *DomService) ListDoms() error { doms, err := d.Conn.ListAllDomains(libvirt.CONNECT_LIST_DOMAINS_ACTIVE) if err != nil { fmt.Println(err) } //fmt.Println(doms) fmt.Printf("%d running domains:\n", len(doms)) for _, dom := range doms { name, err := dom.GetName() if err == nil { fmt.Printf(" %s\n", name) } dom.Free() } return nil } func main() { doms := DomService{} doms.Connect() doms.ListDoms() } -- Regards, Shashwat Shagun

3 2

[libvirt-users] virsh migrate --copy-storage-inc
by Paul van der Vlis 13 Feb '19

13 Feb '19

Hello, I use libvirt on machines without shared storage. My VM's have all one qcow2-disk, with the same name as the VM. When I want to migrate a VM, I check if there is an qcow2 image on the other host with that name. When that's not the case, I copy the image using rsync first. If the image excist, I don't do that, and I think that "--copy-storage-inc" will do it. But I don't know how intelligent "--copy-storage-inc" is. I use LVM inside the VM's, and it's possible that I have changed the size of a volume for example. My questions: Is "--copy-storage-inc" intelligent enough for such tasks? Is there documentation what is done during migration? Is it using rsync? Is it possible to make the migration process more verbose? Is what I do a good way? With regards, Paul van der Vlis BTW: this is what I do, sometimes the lines are broken wrong: ----------- # Rsync image when not on the other host: if test `ssh $other "if test -e /data/$vm.qcow2; then echo ja; else echo nee; fi"` = "nee"; then echo "rsync..." rsync /data/$vm.qcow2 $other://data/$vm.qcow2 if test $? = 0; then echo "gelukt"; else echo "niet gelukt"; exit; fi fi # migrate echo "migrate..." virsh migrate --live --p2p --tunnelled --copy-storage-inc --persistent --undefinesource --verbose $vm qemu+ssh://$other/system if test $? = 0; then echo "gelukt"; else echo "niet gelukt"; exit; fi ----------- -- Paul van der Vlis Linux systeembeheer Groningen https://www.vandervlis.nl/

2 2