November 2016 - Users - libvirt List Archives

[libvirt-users] ceph rbd pool and libvirt manageability (virt-install)
by Jelle de Jong 28 Aug '18

28 Aug '18

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello everybody, I created a rbd pool and activated it, but I can't seem to create volumes in it with virsh or virt-install? # virsh pool-dumpxml myrbdpool <pool type='rbd'> <name>myrbdpool</name> <uuid>2d786f7a-2df3-4d79-ae60-1535bcf1c6b5</uuid> <capacity unit='bytes'>6997998301184</capacity> <allocation unit='bytes'>10309227031</allocation> <available unit='bytes'>6977204658176</available> <source> <host name='ceph01.powercraft.nl' port='6789'/> <host name='ceph02.powercraft.nl' port='6789'/> <host name='ceph03.powercraft.nl' port='6789'/> <name>libvirt-pool</name> <auth type='ceph' username='libvirt'> <secret uuid='029a334e-ed57-4293-bb99-ffafa8867122'/> </auth> </source> </pool> # virt-install --version 1.0.1 # virsh --version 1.2.9 I ended using virsh edit ceph-test.powercraft.nl and making creating the disk manually. <disk type='network' device='disk'> <auth username='libvirt'> <secret type='ceph' uuid='029a334e-ed57-4293-bb99-ffafa8867122'/> </auth> <source protocol='rbd' name='libvirt-pool/kvm01-storage'> <host name='ceph01.powercraft.nl' port='6789'/> <host name='ceph02.powercraft.nl' port='6789'/> <host name='ceph03.powercraft.nl' port='6789'/> </source> <target dev='vdc' bus='virtio'/> </disk> I use virt-install a lot to define, import and undefine domains, how can I use virt-install to manage my rdb disks? Kind regards, Jelle de Jong -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iJwEAQECAAYFAlV1xlQACgkQ1WclBW9j5HkbPQP+PjNrzvlqysslOp2Yk7wH4Mxy 2sh2dn96G0KOAHEeEn3BN6IWlnD1TADZbHdpTtMwkdv48Xwn0sP1s+3QDM4pb3gP n+z+dVxS8FouDIy/eiso3IBCj3g4TWbEX8ZHqs3jKqe0lZgAXBzB9xYSUowcEBrZ ddkPbr8p8ozWyOG+9V8= =lkK7 -----END PGP SIGNATURE-----

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[libvirt-users] virRandomBits - not very random
by Brian Rak 01 Jun '18

01 Jun '18

I just ran into an issue where I had about 30 guests get duplicate mac addresses assigned. These were scattered across 30 different machines. Some debugging revealed that: 1) All the host machines were restarted within a couple seconds of each other 2) All the host machines had fairly similar libvirtd pids (within ~100 PIDs of each other) 3) Libvirt seeds the RNG using 'time(NULL) ^ getpid()' This perfectly explains why I saw so many duplicate mac addresses. Why is the RNG seed such a predictable value? Surely there has to be a better source of a random seed then the timestamp and the pid? The PID seems to me to be a very bad source of any randomness. I just ran a test across 60 of our hosts. 43 of them shared their PID with at least one other machine.

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[libvirt-users] virDomainBlockInfo for local volume
by Shahar Havivi 21 Dec '16

21 Dec '16

Hi, I am using virStorageVolGetInfo to get the volume size virStorageVol.download to download a normal file for VDSM project. I want to add support for block devices as well, I was able to see the size via virDomainBlockInfo and download via virDomain.blockPeek which is works fine for both file and block device. 1. Can I depend on virDomainBlockInfo for non block devices? 2. Does the virDomainBlockInfo return the correct physical size for normal file? 3. Performance wise do we have a difference between virStorageVol.download and virDomain.blockPeek? Assuming the VMs are down, this is the code I intend to use for all formats: vm = con.lookupByName(options.vmname) info = vm.blockInfo(src) physical = info[2] off = 0 size = 0 with open(dest, 'w+') as f: while off < physical: if (physical - off) < bufsize: size = physical - off else: size = bufsize buf = vm.blockPeek(src, off, size) f.write(buf) off += size

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[libvirt-users] Understanding and converting between type='drive' and type='pci'
by Leroy Tennison 02 Dec '16

02 Dec '16

First, if this isn't the right list please tell me where i should post. I've searched for an explanation and I'm either searching for the wrong thing or it's not there. I'm trying to get an understanding of the "controller='0' bus='0' target='0' unit='0' " parameters for 'drive' compared to the "domain='0x0000' bus='0x00' slot='0x05' function='0x0' " parameters for 'pci'. It appears that 'dev hda' to 'dev hdd' is the maximum associated with 'drive', how many are available with 'pci' and what are the valid ranges for those parameters? If I have an xml using 'drive' and want to convert it to 'pci' what do I need to do? I've had trouble with this when moving disk images between hypervisors but have never had the time to investigate fully, does it have to do with how the drives are referenced (/dev/disk/by0id or /dev/[h|s|v]da as opposed to UUID)? Thanks for your help.

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[libvirt-users] sudo user to access xen server remotely.
by ganesh kg 29 Nov '16

29 Nov '16

HI, i am trying to use sudo user to access xen server remotely. As its documented, libvirtd can be accessed only through root user or users from libvirtd usergroup. is there any tweak or possibility to access libvirt remotely through sudo user? or by using certificate? code snippet: #!/usr/bin/env python import sys import libvirt conn = libvirt.open('xen+ssh://sudo_user@xen_server') <== Trying to establish connection to the remote xen using sudo user. if conn == None: print('Failed to open connection to xen+ssh:xen_server') exit(1) host = conn.getHostname() print('Hostname:'+host) conn.close() exit(0)

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[libvirt-users] Routed mode problem with SSH
by Marcelo Palma 27 Nov '16

27 Nov '16

Hi guys, I describe the context of the problem below: I installed a Tor relay on a virtual machine on my server with IP 9.1.1.101. This virtual machine needs to use a static IP (9.1.1.102) to work as a Tor relay. After that I create a virtual network in *Routed mode* to connect to the physical network (used as a bridge between the virtual machine and the external network (Internet)). Since I change the NAT to Routed mode, I can't access my server via ssh user(a)9.1.1.101. Will it be a Routed mode problem? How can I solve this problem? Thank you Marcelo

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[libvirt-users] stream finish throws exception via python API
by Shahar Havivi 27 Nov '16

27 Nov '16

Hi, The following snippet works fine e.g. receiving the data but when calling stream.finish() we get the following error: stream = con.newStream() vol.download(stream, 0, 0, 0) buf = stream.recv(1024) stream.finish() libvirt: I/O Stream Utils error : internal error: I/O helper exited abnormally Traceback (most recent call last): File "./helpers/kvm2ovirt", line 149, in <module> download_volume(vol, item[1], diskno, disksitems, pksize) File "./helpers/kvm2ovirt", line 102, in download_volume stream.finish() File "/usr/lib64/python2.7/site-packages/libvirt.py", line 5501, in finish if ret == -1: raise libvirtError ('virStreamFinish() failed') libvirt.libvirtError: internal error: I/O helper exited abnormally Am I doing something wrong? Thank you, Shahar.

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[libvirt-users] locking domain memory
by Dennis Jacobfeuerborn 26 Nov '16

26 Nov '16

Hi, is there a way to lock a guests memory so it doesn't get swapped out? I now there is memoryBacking->locked but that says it requires memtune->hard_limit and the description of that basically "don't ever do this" rendering the locked element kind of pointless. How can I prevent the guests memory from being swapped out without shooting myself in the foot? Regards, Dennis

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[libvirt-users] NUMA VM and assigning interfaces
by Amir Shehata 26 Nov '16

26 Nov '16

Hello, Hope all is well. I've been looking at how I can create a virtual machine which is NUMA capable. I was able to do that by: 140 <qemu:commandline> 143 <qemu:arg value='-numa'/> 144 <qemu:arg value='node'/> 145 <qemu:arg value='-numa'/> 146 <qemu:arg value='node'/> 147 </qemu:commandline> This creates two NUMA nodes. Now I would like to assign my virtual network interfaces, of which I have three, to the different NUMA nodes on the VM. Anyone know how I can do that? Any help/pointers would be much appreciated. I'm trying to create a VM that will enable me to test a NUMA based feature. thanks amir

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[libvirt-users] Fwd: Re: Attach libvirt guest to an existing openvswitch port
by Ivan Borodin 25 Nov '16

25 Nov '16

Thank you, Laine for you time and patience to give me a detailed answer. I missed the interfaceid parameter in the docs, but now I didn't manage to get it working. > http://www.libvirt.org/formatdomain.html The docs state: "The Open vSwitch type virtualport accepts two parameters in its <parameters> element - an interfaceid which is a standard uuid used to uniquely identify this particular interface to Open vSwitch (if you do not specify one, a random interfaceid will be generated for you when you first define the interface[...]" This interfaceid doesn't seem to have anything to do with ovsdb values. $ ovs-vsctl find Port 'name=vm_test' _uuid : f0f06327-6fcc-4073-b8c8-3f42944d43ca bond_downdelay : 0 bond_fake_iface : false bond_mode : [] bond_updelay : 0 external_ids : {} fake_bridge : false interfaces : [eb7fad6e-3728-4bf7-b31e-4a1693e2ec4b] lacp : [] mac : [] name : "vm_test" other_config : {} qos : [] statistics : {} status : {} tag : [] trunks : [] vlan_mode : [] The "_uuid" is ovsdb internal id of a record. If you take "interfaces" value for "interfaceid", libvirt will silently create its own new ovs port, with its own new uuid and defining a libvirt guest's interface with a unique uuid in "interfaceid"... Libvirt will create a new ovs port, and the ovsdb-"interfaces" value will be the interfaceid... And I could not find anything specific about this ovsdb/Port/interfaces. Actually, my point was to find a way to control ovs vlans outside libvirt. Since virsh doesn't have capabilities to edit interface's vlan options, the only way to do it is editing domains' xml-configs through virsh-edit, which is a bit tiresome. (By the way, there must be some technical reason(beyond virt-xml-validate) for designing libvirt writing it's own configuration files instead of reading them...) There should be.. There must be a way to do this. Port parameters are ovs authority. If there is no such way, could you, please, tell me the reason. On 11/21/2016 09:46 PM, Laine Stump wrote: > On 11/13/2016 01:23 PM, Ivan Borodin wrote: >> Somehow with interface types 'bridge' and 'network', libvirt does attach >> domain to the existing port specified in <target dev=''/>, wiping the >> exixting settings and always deletes this port upon domain shutdown, >> thus making me loose ovs configuration.

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[libvirt-users] virt-manager wont connect to remote libvirt instance
by bherman 23 Nov '16

23 Nov '16

I am using virt-manager on debian 8 and I am remotely connecting to a libvirt instance on a server. It was all working fine until today when I discovered that I cannot remotely connect to the libvirt server anymore. ● libvirtd.service - Virtualization daemon Loaded: loaded (/lib/systemd/system/libvirtd.service; enabled) Active: active (running) since Tue 2016-11-22 10:27:09 CST; 46min ago Docs: man:libvirtd(8) http://libvirt.org Process: 27630 ExecReload=/bin/kill -HUP $MAINPID (code=exited, status=0/SUCCESS) Main PID: 27823 (libvirtd) CGroup: /system.slice/libvirtd.service ├─ 4787 /usr/sbin/libvirtd ├─ 8187 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --dhcp-script=/usr/lib/libvi... ├─ 8188 /usr/sbin/dnsmasq --conf-file=/var/lib/libvirt/dnsmasq/default.conf --dhcp-script=/usr/lib/libvi... └─27823 /usr/sbin/libvirtd It says it is running however I cant connect to it either remotely or on the server using virt-manager. When I do a virsh --list It just hangs and doesn't output anything. Any ideas? -- Thanks, Brian Herman IT O: (773)299-7557 F: (773)299-7505

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[libvirt-users] Routed mode problem with SSH
by Marcelo Palma 22 Nov '16

22 Nov '16

Hi guys, I describe the context of the problem below: I installed a Tor relay on a virtual machine on my server with IP 9.1.1.101. This virtual machine needs to use a static IP (9.1.1.102) to work as a Tor relay. After that I create a virtual network in *Routed mode* to connect to the physical network (used as a bridge between the virtual machine and the external network (Internet)). Since I change the NAT to Routed mode, I can't access my server via ssh user(a)9.1.1.101. Will it be a Routed mode problem? How can I solve this problem? Thank you Marcelo

1 0

[libvirt-users] blockcommit and gluster network disk path
by Sahina Bose 22 Nov '16

22 Nov '16

Hi, I'm running into problems with blockcommit and gluster network disks - wanted to check how to pass path for network disks. How's the protocol and host parameters specified? For a backing volume chain as below, executing virsh blockcommit fioo5 vmstore/912d9062-3881-479b-a6e5-7b074a252cb6/images/27b0cbcb-4dfd-4eeb-8ab0-8fda54a6d8a4/027a3b37-77d4-4fa9-8173-b1fedba1176c --base vmstore/912d9062-3881-479b-a6e5-7b074a252cb6/images/27b0cbcb-4dfd-4eeb-8ab0-8fda54a6d8a4/d4c23ec6-20ce-4a2f-9b32-ca91e65a114a --top vmstore/912d9062-3881-479b-a6e5-7b074a252cb6/images/27b0cbcb-4dfd-4eeb-8ab0-8fda54a6d8a4/027a3b37-77d4-4fa9-8173-b1fedba1176c --verbose --wait gives "error: invalid argument: No device found for specified path". <disk type='network' device='disk' snapshot='no'> <driver name='qemu' type='qcow2' cache='none' error_policy='stop' io='threads'/> <source protocol='gluster' name='vmstore/912d9062-3881-47 9b-a6e5-7b074a252cb6/images/27b0cbcb-4dfd-4eeb-8ab0-8fda54a6 d8a4/027a3b37-77d4-4fa9-8173-b1fedba1176c'> <host name='10.70.37.28' port='0'/> </source> <backingStore type='network' index='1'> <format type='qcow2'/> <source protocol='gluster' name='vmstore/912d9062-3881-47 9b-a6e5-7b074a252cb6/images/27b0cbcb-4dfd-4eeb-8ab0-8fda54a6 d8a4/d4c23ec6-20ce-4a2f-9b32-ca91e65a114a'> <host name='10.70.37.28' port='0'/> </source> <backingStore type='network' index='2'> <format type='raw'/> <source protocol='gluster' name='vmstore/912d9062-3881-47 9b-a6e5-7b074a252cb6/images/27b0cbcb-4dfd-4eeb-8ab0-8fda54a6 d8a4/f5098809-e719-404b-8d80-3f824f4333a2'> <host name='10.70.37.28' port='0'/> </source> <backingStore/> </backingStore> </backingStore> <target dev='vda' bus='virtio'/> <serial>27b0cbcb-4dfd-4eeb-8ab0-8fda54a6d8a4</serial> <boot order='2'/> <alias name='virtio-disk0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/> </disk> thanks sahina

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[libvirt-users] Attach libvirt guest to an existing openvswitch port
by Ivan Borodin 21 Nov '16

21 Nov '16

Good day gentlemen. I am building a study project and trying to configure openvswitch vlans outside libvirt by means of openvswitch itself. Somehow with interface types 'bridge' and 'network', libvirt does attach domain to the existing port specified in <target dev=''/>, wiping the exixting settings and always deletes this port upon domain shutdown, thus making me loose ovs configuration. Could you, please, tell me how should I configure an interface or libvirt itself to avoid this libvirt's greedines. libvirt 2.4.0 Thak you. Ivan.

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[libvirt-users] export a cert
by lejeczek 21 Nov '16

21 Nov '16

hi everybody I'm browsing around but probably missing that obvious little thing - exporting certs to pem format with ipa command toolkit - that must be there somewhere, right? thanks, L.

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[libvirt-users] ergodox keyboard not working on USB hostdev passthrough
by Paul Handy 16 Nov '16

16 Nov '16

I'm using a bit of a different keyboard, the infinity ergodox [ https://input.club/devices/infinity-ergodox/] It functions just fine as a keyboard on my host computer, but when I try to bind it to the guest, nothing seems to happen. lsusb gives its ID: Bus 006 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub *Bus 005 Device 003: ID 1c11:b04d* Bus 005 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub Bus 001 Device 003: ID 258a:0001 Bus 001 Device 002: ID 093a:2521 Pixart Imaging, Inc. Optical Mouse Bus 001 Device 004: ID 8087:0a2b Intel Corp. Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub So, I made a file, hostdev-1c11:b04d.xml, which contains the following: <hostdev mode='subsystem' type='usb' > <source> <vendor id='0x1c11'/> <product id='0xb04d'/> </source> </hostdev> Note, I have had this same xml inside the domain's xml, but have pulled it out separately so that I could run: virsh attach-device linux-x86_64 hostdev-1c11:b04d.xml It appears to attach the device, as it becomes visible in the domain's lsusb: Bus 001 Device 001: ID 1d6b:0002 Bus 004 Device 001: ID 1d6b:0001 *Bus 003 Device 003: ID 1c11:b04d * Bus 003 Device 001: ID 1d6b:0001 Bus 002 Device 003: ID 093a:2521 Bus 002 Device 002: ID 258a:0001 Bus 002 Device 001: ID 1d6b:0001 The mouse works just fine. I bought a cheap keyboard to test out, and it works just fine. My pet keyboard, however, doesn't work on the guest. Nothing seems to register. Any ideas here what I could do? Drivers? ROM's? I've tried both SeaBIOS and OVMF with no difference in outcome, and while this appears to be a hardware problem, I don't know where to begin. Thanks, Paul

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[libvirt-users] BroadCom NIC not adding as PassThrough device
by Tahir Masood 16 Nov '16

16 Nov '16

Hi Guys, I am trying to add a Broadcom Physical NIC to a virtual Machine as Passthrough device. However I am getting following error. Error starting domain: unsupported configuration: host doesn't support passthrough of host PCI devices Traceback (most recent call last): File "/usr/share/virt-manager/virtManager/asyncjob.py", line 88, in cb_wrapper callback(asyncjob, *args, **kwargs) File "/usr/share/virt-manager/virtManager/asyncjob.py", line 124, in tmpcb callback(*args, **kwargs) File "/usr/share/virt-manager/virtManager/libvirtobject.py", line 83, in newfn ret = fn(self, *args, **kwargs) File "/usr/share/virt-manager/virtManager/domain.py", line 1404, in startup self._backend.create() File "/usr/lib64/python2.7/site-packages/libvirt.py", line 1035, in create if ret == -1: raise libvirtError ('virDomainCreate() failed', dom=self) libvirtError: unsupported configuration: host doesn't support passthrough of host PCI devices libvirt allows to appply the changes to the VM xml configurations, but gives error the moment I try to start the VM. I have tried following approaches. 1- Open Virt-Manager, Shutdown VM, edit VM , add PCI hardware device , locate BroadCom NIC, apply changes. Then I restart the VM. 2- Also tried to add following XML tags one by one using 'virsh edit', but got same error. Tag -1 <hostdev mode='subsystem' type='pci' managed='yes'> <source> <address domain='0x0000' bus='0x02' slot='0x00' function='0x1'/> </source> </hostdev> Tag -2 <interface type='hostdev' managed='yes'> <source> <address type='pci' domain='0x0000' bus='0x02' slot='0x00' function='0x1'/> </source> </interface> The detail of the BroadCOm NIC are as follows. 02:00.1 Ethernet controller: Broadcom Limited NetXtreme II BCM5709 Gigabit Ethernet (rev 20) What would it take to add this NIC to VM as Passthrough Device? Regards, Tahir Masood Senior Engineer, xFlow Research Inc. +92-300-9779473 <mailto:tahir.masood@xflowresearch.com> tahir.masood(a)xflowresearch.com <http://www.xflowresearch.com/> www.xflowresearch.com

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[libvirt-users] how to use command 'guest-file-open' for Windows server 2012R2 vm
by 刘梦可 09 Nov '16

09 Nov '16

hello, I am using libvirt 1.2.17 on CentOS 7.2 - kernel 3.10.0-327.13.1.el7.x86_64. The command guest-file-open failed to open with error "this feature or command is not currently supported", the detail is as below: virsh qemu-agent-command instance-00000015 "{\"execute\":\"guest-file-open\", \"arguments\":{\"path\":\"\tmp.txt\",\"mode\":\"r\"}}" error: internal error: unable to execute QEMU agent command 'guest-file-open': this feature or command is not currently supported. The guest instance-00000015 is a Windows server 2012R2, and I installed the qemu-guest-agent by the file qemu-ga-x64.msi from virtio-win-0.1.126. It can be running in guest. Doesn't the qemu-guest-agent in Windows VM support guest-file-* commands? How or when can I use the command guest-file-* command? Thanks very much!! -mkliu28

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[libvirt-users] sttic vnet device for guest
by Anton Gorlov 08 Nov '16

08 Nov '16

Can i assign static vnet* device for some guests?

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[libvirt-users] Guest startup process blocks if a hook's child process is still running (i.e : after forking)
by Nicolas Roy-Renaud 08 Nov '16

08 Nov '16

I've been having issues with KVM lately where I sometimes put my host into sleep while a guest is still running, which prevents it from waking up properly. This is somewhat expected due to my setup, but I have mistakenly done this more than once and could use a workaround to stop this from happening. So I've been trying to setup a libvirt hook to fork an instance of systemd-inhibit when the start hook is called and keep it running until the shutdown hook is called. This seems to work well when I run the hook script in a normal bash shell, but running it through libvirt simply blocks the starting process until systemd-inhibit quits. Here's the script : LOCK_FILE="/tmp/vfio-lock-$OBJECT" if [ "$OPERATION" == "start" ]; then ( touch "$LOCK_FILE"; systemd-inhibit --what="sleep" \ --who="libvirt" \ --mode="block" \ inotifywait -qq -e delete "$LOCK_FILE" ) & disown $! exit fi if [ "$OPERATION" == "shutdown" ]; then rm "$LOCK_FILE" fi Is there some way to make it so libvirt sees the hook script exiting and carries on with the rest of its guest startup process even after a process fork or would that require changes in the internal hook handling functions? - Nicolas

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[libvirt-users] Sharing network namespace between containers
by Harish Vishwanath 08 Nov '16

08 Nov '16

Hello Based on the lxc driver documentation, I am trying to create an xml to share an existing network namespace with another container. I am running libvirt 1.2.15. Here is the xml: <domain type='lxc' xmlns:lxc='http://libvirt.org/schemas/domain/lxc/1.0'> <name>nt</name> <uuid>43c00192-e114-4e29-8ce7-4b5487f60a75</uuid> <memory unit='KiB'>65536</memory> <currentMemory unit='KiB'>65536</currentMemory> <vcpu placement='static'>1</vcpu> <cputune> <shares>2000</shares> </cputune> <resource> <partition>/apphosting.partition</partition> </resource> <os> <type arch='x86_64'>exe</type> <init>/sbin/init</init> </os> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>destroy</on_crash> <devices> <emulator>/usr/lib/libvirt/libvirt_lxc</emulator> <filesystem type='mount' accessmode='passthrough'> <source dir='/work/repo-lxc/nt/rootfs_mnt'/> <target dir='/'/> </filesystem> <filesystem type='mount' accessmode='squash'> <driver type='path' wrpolicy='immediate'/> <source dir='/local/local1/core_dir/nt'/> <target dir='/local/local1/core_dir'/> </filesystem>  <console type='pty'> <target type='lxc' port='0'/> </console> </devices> * <lxc:namespace>* * <lxc:sharenet type='netns' value='node'/>* * </lxc:namespace>* </domain> However, the virsh edit is unable to save this file: error: XML document failed to validate against schema: Unable to validate doc against /usr/share/libvirt/schemas/domain.rng Element domain has extra content: namespace Failed. Try again? [y,n,i,f,?]: Is this supported in libvirt 1.2.15 - the document doesnt specify a minimum version of libvirt. Appreciate your help. Regards, Harish

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[libvirt-users] virtual wlan0
by Michael Ströder 07 Nov '16

07 Nov '16

HI! My goal is to run a virtualized access point with hostapd. Is it possible to use the host's WIFI interface in a VM created with libvirt? I can add the interface in bridged mode but it appears just as normal eth1 without wireless extensions. Ciao, Michael.

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[libvirt-users] pci-assign fails with read error on config-space file
by Henning Schild 02 Nov '16

02 Nov '16

Hey, i am running an unusual setup where i assign pci devices behind the back of libvirt. I have two options to do that: 1. a wrapper script for qemu that takes care of suid-root and appends arguments for pci-assign 2. virsh qemu-monitor-command ... 'device_add pci-assign...' I know i should probably not be doing this, it is a workaround to introduce fine-grained pci-assignment in an openstack setup, where vendor and device id are not enough to pick the right device for a vm. In both cases qemu will crash with the following output: > qemu: hardware error: pci read failed, ret = 0 errno = 22 followed by the usual machine state dump. With strace i found it to be a failing read on the config space file of my device. /sys/bus/pci/devices/0000:xx:xx.x/config A few reads out of that file succeeded, as well as accesses on vendor etc. Manually launching a qemu with the pci-assign works without a problem, so i "blame" libvirt and the cgroup environment the qemu ends up in. So i put a bash into the exact same cgroup setup - next to a running qemu, expecting a dd or hexdump on the config-space file to fail. But from that bash i can read the file without a problem. Has anyone seen that problem before? Right now i do not know what i am missing, maybe qemu is hitting some limits configured for the cgroups or whatever. I can not use pci-assign from libvirt, but if i did would it configure cgroups in a different way or relax some limits? What would be a good next step to debug that? Right now i am looking at kernel event traces, but the machine is pretty big and so is the trace. That assignment used to work and i do not know how it broke, i have tried combinations of several kernels, versions of libvirt and qemu. (kernel 3.18 and 4.4, libvirt 1.3.2 and 2.0.0, and qemu 2.2.1 and 2.7) All combinations show the same problem, even the ones that work on other machines. So when it comes to software versions the problem could well be caused by a software update of another component, that i got with the package manager and did not compile myself. It is a debian 8.6 with all recent updates installed. My guess would be that systemd could have an influence on cgroups or limits causing such a problem. regards, Henning

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[libvirt-users] pass-through hwrng
by lejeczek 01 Nov '16

01 Nov '16

hi all I have in my centos 7 this: crw-------. 1 root root 10, 183 Oct 11 21:28 /dev/hwrng and VM fails, complains like this: virsh # start volatile-work6 error: Failed to start domain volatile-work6 error: internal error: process exited while connecting to monitor: 2016-10-19T09:42:05.988142Z qemu-kvm: -object rng-random,id=objrng0,filename=/dev/hwrng: Could not open '/dev/hwrng': Permission denied which reads logical. Now - is this normal that hwrng is created with these permissions? And if yes then how to pass-through it to the VMs? How to aid VMs with hardware random numbers generator? many thanks. L

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