March 2016 - Users - libvirt List Archives

[libvirt-users] Virtual Netwok manager and cmd
by Mohsen Pahlevanzadeh 23 Mar '16

23 Mar '16

Dear All, I'm reading the following pages: http://wiki.libvirt.org/page/TaskRoutedNetworkSetupVirtManager http://wiki.libvirt.org/page/TaskNATSetupVirtManager http://wiki.libvirt.org/page/TaskIsolatedNetworkSetupVirtManager routed mode, NAT mode and Isolated mode, But above pages explain with GUI, a sysadmin forgets GUI... Question is What's replacement of above command? ---Best Regards Mohsen

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[libvirt-users] changing clock on host temporarily blocks guest OS operation
by Andrei Perietanu 22 Mar '16

22 Mar '16

I have the following running on my system: - one linux host running libvirt 1.2.20 - two Linux guestOS VMs running When I change the clock on the host, the VMs stop responding: The VNC connection stops working, the console connection to the VMs does not work, ping stops reponding, libvirt commands temporarily stop working (after issuing the command, the system just hangs). I get control back after 5 min or so, but I have to restart the VMs for everything to work again. Any ideas what's causing this? Is this a know bug? Is there a fix for it? Thanks in advance, Andrei -- The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential and/or privileged material. Any review, retransmission, dissemination or other use of or taking of any action in reliance upon this information by persons or entities other than the intended recipient is prohibited. If you receive this in error please contact the sender and delete the material from any computer immediately. It is the policy of Klas Limited to disavow the sending of offensive material and should you consider that the material contained in the message is offensive you should contact the sender immediately and also your I.T. Manager. Klas Telecom Inc., a Virginia Corporation with offices at 1101 30th St. NW, Washington, DC 20007. Klas Limited (Company Number 163303) trading as Klas Telecom, an Irish Limited Liability Company, with its registered office at Fourth Floor, One Kilmainham Square, Inchicore Road, Kilmainham, Dublin 8, Ireland.

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[libvirt-users] virtual machine won't autostart when using LVM with cache
by David Hlacik 21 Mar '16

21 Mar '16

Hello guys, Recently I have switched to use LVM cache feature on logical volume /dev/hdd/windata1 to improve it performace using 32GB partition from SSD disk. However, when my computer will start, my virtual machine won't autostart Mar 21 10:48:57 brutus-coreos libvirtd[956]: Cannot access storage file '/dev/hdd/windata1' (as uid:107, gid:107): No such file or directory Mar 21 10:48:57 brutus-coreos libvirtd[956]: Failed to autostart VM 'winos1': Cannot access storage file '/dev/hdd/windata1' (as uid:107, gid:107): No such file or directory Mar 21 10:48:57 brutus-coreos libvirtd[956]: Cannot access storage file '/dev/hdd/windata1' (as uid:107, gid:107): No such file or directory It seems that when using LVM cache, one have to wait till it will inicialize? When I will manually start virtual machine afterwards, everything works OK : [root@brutus-coreos ~]# virsh start winos1 Domain winos1 started I have tried to remove LVM cache from /dev/hdd/windata1 and afterward autostart works! So it must be LVM cache related. Can you please help me to solve this ? Thanks in advance David Hlacik +420-777-307-745 | david(a)hlacik.cz [image: View David Hlacik's profile on LinkedIn] <http://cz.linkedin.com/in/hlacik>

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[libvirt-users] Libvirt bite sized tasks
by Michal Privoznik 20 Mar '16

20 Mar '16

Dear lists, I've just started new wiki page which aim is to summarize small and trivial tasks, that starting contributors can take, investigate and implement. The aim is to give them something easy to start with while not scaring them out about complexity of our code. The page can be found here: http://wiki.libvirt.org/page/BiteSizedTasks The name is copied from qemu wiki: http://wiki.qemu.org/BiteSizedTasks Please, feel free to extend the list. I plan to use it in the future when interviewing GSoC candidates. Michal

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[libvirt-users] Incorrect memory usage returned from virsh
by Connor Osborn 18 Mar '16

18 Mar '16

When I run `virsh dominfo <domain>` I get the following: Id: 455 Name: instance-000047e0 UUID: 50722aa0-d5c6-4a68-b4ef-9b27beba48aa OS Type: hvm State: running CPU(s): 4 CPU time: 123160.4s Max memory: 33554432 KiB Used memory: 33554432 KiB Persistent: yes Autostart: disable Managed save: no Security model: apparmor Security DOI: 0 Security label: libvirt-50722aa0-d5c6-4a68-b4ef-9b27beba48aa (enforcing) The domain is not at 100% memory capacity. How can I diagnose this further?

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[libvirt-users] Can I use 'virsh save' this command only get 'vm physical memory' ? If not , please tell me how can I get it .
by Leekitty 18 Mar '16

18 Mar '16

Can I use 'virsh save' this command only get 'vm physical memory' ? If not ,please tell me how can I get it . Thanks in advance. Lee Wen

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[libvirt-users] CfP 11th Workshop on Virtualization in High-Performance Cloud Computing (VHPC '16)
by VHPC 16 18 Mar '16

18 Mar '16

==================================================================== CALL FOR PAPERS 11th Workshop on Virtualization in High-Performance Cloud Computing (VHPC '16) held in conjunction with the International Supercomputing Conference - High Performance, June 19-23, 2016, Frankfurt, Germany. ==================================================================== Date: June 23, 2016 Workshop URL: http://vhpc.org Paper Submission Deadline: April 25, 2016 Call for Papers Virtualization technologies constitute a key enabling factor for flexible resource management in modern data centers, and particularly in cloud environments. Cloud providers need to manage complex infrastructures in a seamless fashion to support the highly dynamic and heterogeneous workloads and hosted applications customers deploy. Similarly, HPC environments have been increasingly adopting techniques that enable flexible management of vast computing and networking resources, close to marginal provisioning cost, which is unprecedented in the history of scientific and commercial computing. Various virtualization technologies contribute to the overall picture in different ways: machine virtualization, with its capability to enable consolidation of multiple underutilized servers with heterogeneous software and operating systems (OSes), and its capability to live-migrate a fully operating virtual machine (VM) with a very short downtime, enables novel and dynamic ways to manage physical servers; OS-level virtualization (i.e., containerization), with its capability to isolate multiple user-space environments and to allow for their coexistence within the same OS kernel, promises to provide many of the advantages of machine virtualization with high levels of responsiveness and performance; I/O Virtualization allows physical NICs/HBAs to take traffic from multiple VMs or containers; network virtualization, with its capability to create logical network overlays that are independent of the underlying physical topology and IP addressing, provides the fundamental ground on top of which evolved network services can be realized with an unprecedented level of dynamicity and flexibility; the increasingly adopted paradigm of Software-Defined Networking (SDN) promises to extend this flexibility to the control and data planes of network paths. Topics of Interest The VHPC program committee solicits original, high-quality submissions related to virtualization across the entire software stack with a special focus on the intersection of HPC and the cloud. Topics include, but are not limited to: - Virtualization in supercomputing environments, HPC clusters, cloud HPC and grids - OS-level virtualization including container runtimes (Docker, rkt et al.) - Lightweight compute node operating systems/VMMs - Optimizations of virtual machine monitor platforms, hypervisors - QoS and SLA in hypervisors and network virtualization - Cloud based network and system management for SDN and NFV - Management, deployment and monitoring of virtualized environments - Virtual per job / on-demand clusters and cloud bursting - Performance measurement, modelling and monitoring of virtualized/cloud workloads - Programming models for virtualized environments - Virtualization in data intensive computing and Big Data processing - Cloud reliability, fault-tolerance, high-availability and security - Heterogeneous virtualized environments, virtualized accelerators, GPUs and co-processors - Optimized communication libraries/protocols in the cloud and for HPC in the cloud - Topology management and optimization for distributed virtualized applications - Adaptation of emerging HPC technologies (high performance networks, RDMA, etc..) - I/O and storage virtualization, virtualization aware file systems - Job scheduling/control/policy in virtualized environments - Checkpointing and migration of VM-based large compute jobs - Cloud frameworks and APIs - Energy-efficient / power-aware virtualization The Workshop on Virtualization in High-Performance Cloud Computing (VHPC) aims to bring together researchers and industrial practitioners facing the challenges posed by virtualization in order to foster discussion, collaboration, mutual exchange of knowledge and experience, enabling research to ultimately provide novel solutions for virtualized computing systems of tomorrow. The workshop will be one day in length, composed of 20 min paper presentations, each followed by 10 min discussion sections, plus lightning talks that are limited to 5 minutes. Presentations may be accompanied by interactive demonstrations. Important Dates April 25, 2016 - Paper submission deadline May 30, 2016 Acceptance notification June 23, 2016 - Workshop Day July 25, 2016 - Camera-ready version due Chair Michael Alexander (chair), TU Wien, Austria Anastassios Nanos (co-chair), NTUA, Greece Balazs Gerofi (co-chair), RIKEN Advanced Institute for Computational Science, Japan Program committee Stergios Anastasiadis, University of Ioannina, Greece Costas Bekas, IBM Research, Switzerland Jakob Blomer, CERN Ron Brightwell, Sandia National Laboratories, USA Roberto Canonico, University of Napoli Federico II, Italy Julian Chesterfield, OnApp, UK Stephen Crago, USC ISI, USA Christoffer Dall, Columbia University, USA Patrick Dreher, MIT, USA Robert Futrick, Cycle Computing, USA Robert Gardner, University of Chicago, USA William Gardner, University of Guelph, Canada Wolfgang Gentzsch, UberCloud, USA Kyle Hale, Northwestern University, USA Marcus Hardt, Karlsruhe Institute of Technology, Germany Krishna Kant, Templte University, USA Romeo Kinzler, IBM, Switzerland Brian Kocoloski, University of Pittsburgh, USA Kornilios Kourtis, IBM Research, Switzerland Nectarios Koziris, National Technical University of Athens, Greece John Lange, University of Pittsburgh, USA Nikos Parlavantzas, IRISA, France Kevin Pendretti, Sandia National Laboratories, USA Che-Rung Roger Lee, National Tsing Hua University, Taiwan Giuseppe Lettieri, University of Pisa, Italy Qing Liu, Oak Ridge National Laboratory, USA Paul Mundt, Adaptant, Germany Amer Qouneh, University of Florida, USA Carlos Reaño, Technical University of Valencia, Spain Seetharami Seelam, IBM Research, USA Josh Simons, VMWare, USA Borja Sotomayor, University of Chicago, USA Dieter Suess, TU Wien, Austria Craig Stewart, Indiana University, USA Anata Tiwari, San Diego Supercomputer Center, USA Kurt Tutschku, Blekinge Institute of Technology, Sweden Amit Vadudevan, Carnegie Mellon University, USA Yasuhiro Watashiba, Osaka University, Japan Nicholas Wright, Lawrence Berkeley National Laboratory, USA Chao-Tung Yang, Tunghai University, Taiwan Gianluigi Zanetti, CRS4, Italy Paper Submission-Publication Papers submitted to the workshop will be reviewed by at least two members of the program committee and external reviewers. Submissions should include abstract, key words, the e-mail address of the corresponding author, and must not exceed 10 pages, including tables and figures at a main font size no smaller than 11 point. Submission of a paper should be regarded as a commitment that, should the paper be accepted, at least one of the authors will register and attend the conference to present the work. The format must be according to the Springer LNCS Style. Initial submissions are in PDF; authors of accepted papers will be requested to provide source files. Format Guidelines: ftp://ftp.springer.de/pub/tex/latex/llncs/latex2e/llncs2e.zip Abstract, Paper Submission Link: https://edas.info/newPaper.php?c=21801 Lightning Talks Lightning Talks are non-paper track, synoptical in nature and are strictly limited to 5 minutes. They can be used to gain early feedback on ongoing research, for demonstrations, to present research results, early research ideas, perspectives and positions of interest to the community. Submit abstract via the main submission link. General Information The workshop is one day in length and will be held in conjunction with the International Supercomputing Conference - High Performance (ISC) 2016, June 19-23, Frankfurt, Germany.

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[libvirt-users] save - restore problem
by Fırat KÜÇÜK 18 Mar '16

18 Mar '16

I was trying to live-migrate a VM. I have not succeeded for now. Instead live-migration Just tried simple save and restore action in same host. virsh save my-domain my-domain.saved virsh restore my-domain.saved Everything seems fine after restoring. But after 5 minutes VM halted. No network connectivity. No response to VNC keystrokes. Totally halted. Is there any suggestion?

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[libvirt-users] Fwd: [Issue]: Regarding client socket getting closed from the server once the lxc container is started
by rammohan madhusudan 18 Mar '16

18 Mar '16

Hi Folks, Using libvirt python bindings we are creating an lxc container.Here is the problem that we see sometimes (say 20 % of the time) when we create a new container. 1.container gets created, and also starts.However the we are not able to enter the namepace of the container.It throws an error initPid not available.We see that the using netstat command , socket connection is closed. 2.To get around this problem we have to stop and start the container again.We see that socket under (/var/run/libvirt/*) connection is established and we are able to enter the namespace. Enabled the libvirtd debug logs to debug this issue. For *success* case we see that for new client connection gets created and is able to handle async incoming events, *2016-03-12 08:18:55.748+0000: 1247: info : virObjectNew:202 : OBJECT_NEW: obj=0x7fed54005460 classname=virLXCMonitor* *2016-03-12 08:18:55.748+0000: 1247: debug : virNetSocketNew:159 : localAddr=0x7fed7cd1d170 remoteAddr=0x7fed7cd1d200 fd=28 errfd=-1 pid=0* *2016-03-12 08:18:55.749+0000: 1247: info : virObjectNew:202 : OBJECT_NEW: obj=0x7fed54009040 classname=virNetSocket* *2016-03-12 08:18:55.749+0000: 1247: info : virNetSocketNew:209 : RPC_SOCKET_NEW: sock=0x7fed54009040 fd=28 errfd=-1 pid=0 localAddr=127.0.0.1;0, remoteAddr=127.0.0.1;0* *2016-03-12 08:18:55.749+0000: 1247: info : virObjectNew:202 : OBJECT_NEW: obj=0x7fed54009d10 classname=virNetClient* *2016-03-12 08:18:55.749+0000: 1247: info : virNetClientNew:327 : RPC_CLIENT_NEW: client=0x7fed54009d10 sock=0x7fed54009040* *2016-03-12 08:18:55.749+0000: 1247: info : virObjectRef:296 : OBJECT_REF: obj=0x7fed54009d10* *2016-03-12 08:18:55.749+0000: 1247: info : virObjectRef:296 : OBJECT_REF: obj=0x7fed54009040* *2016-03-12 08:18:55.750+0000: 1247: info : virObjectNew:202 : OBJECT_NEW: obj=0x7fed540009a0 classname=virNetClientProgram* *2016-03-12 08:18:55.750+0000: 1247: info : virObjectRef:296 : OBJECT_REF: obj=0x7fed540009a0* *2016-03-12 08:18:55.750+0000: 1247: info : virObjectRef:296 : OBJECT_REF: obj=0x7fed54005460* *2016-03-12 08:18:55.750+0000: 1247: info : virObjectUnref:259 : OBJECT_UNREF: obj=0x7fed5c168eb0* *2016-03-12 08:18:55.750+0000: 1247: debug : virLXCProcessCleanInterfaces:475 : Cleared net names: eth0 * *2016-03-12 08:18:55.750+0000: 1247: info : virObjectUnref:259 : OBJECT_UNREF: obj=0x7fed5c168eb0* *2016-03-12 08:18:55.750+0000: 1247: info : virObjectUnref:259 : OBJECT_UNREF: obj=0x7fed5c169600* *2016-03-12 08:18:55.755+0000: 1244: debug : virNetClientIncomingEvent:1808 : client=0x7fed54009d10 wantclose=0* *2016-03-12 08:18:55.755+0000: 1244: debug : virNetClientIncomingEvent:1816 : Event fired 0x7fed54009040 1* *2016-03-12 08:18:55.755+0000: 1244: debug : virNetMessageDecodeLength:151 : Got length, now need 36 total (32 more)* *2016-03-12 08:18:55.756+0000: 1244: info : virNetClientCallDispatch:1116 : RPC_CLIENT_MSG_RX: client=0x7fed54009d10 len=36 prog=305402420 vers=1 proc=2 type=2 status=0 serial=1* *2016-03-12 08:18:55.756+0000: 1244: debug : virKeepAliveCheckMessage:377 : ka=(nil), client=0x7fed81fc5ed4, msg=0x7fed54009d78* *2016-03-12 08:18:55.756+0000: 1244: debug : virNetClientProgramDispatch:220 : prog=305402420 ver=1 type=2 status=0 serial=1 proc=2* *2016-03-12 08:18:55.756+0000: 1244: debug : virLXCMonitorHandleEventInit:109 : Event init 1420 * For *failure* case ,we see that the client socket connection is initiated and gets closed immediately after receiving an incoming event.In this case, I don’t see an object for virNetClientProgram being created. Incoming event comes in and since the its unable to find client->prog it bails out and closes the connection. Snaphost of the code, static int virNetClientCallDispatchMessage(virNetClientPtr client) { size_t i; virNetClientProgramPtr prog = NULL; for (i = 0; i < client->nprograms; i++) { if (virNetClientProgramMatches(client->programs[i], &client->msg)) { prog = client->programs[i]; break; } } if (!prog) { * VIR_DEBUG("No program found for event with prog=%d vers=%d",* * client->msg.header.prog, client->msg.header.vers);* return -1; } *2016-03-12 08:19:15.935+0000: 1246: info : virObjectRef:296 : OBJECT_REF: obj=0x7fed5c168eb0* *2016-03-12 08:19:15.935+0000: 1246: info : virObjectRef:296 : OBJECT_REF: obj=0x7fed82bd7bc0* *2016-03-12 08:19:15.935+0000: 1246: info : virObjectNew:202 : OBJECT_NEW: obj=0x7fed82bd8120 classname=virLXCMonitor* *2016-03-12 08:19:15.935+0000: 1246: debug : virNetSocketNew:159 : localAddr=0x7fed7d51e170 remoteAddr=0x7fed7d51e200 fd=31 errfd=-1 pid=0* *2016-03-12 08:19:15.936+0000: 1246: info : virObjectNew:202 : OBJECT_NEW: obj=0x7fed82bd8660 classname=virNetSocket* *2016-03-12 08:19:15.936+0000: 1246: info : virNetSocketNew:209 : RPC_SOCKET_NEW: sock=0x7fed82bd8660 fd=31 errfd=-1 pid=0 localAddr=127.0.0.1;0, remoteAddr=127.0.0.1;0* *2016-03-12 08:19:15.936+0000: 1246: info : virObjectNew:202 : OBJECT_NEW: obj=0x7fed82bd8ca0 classname=virNetClient* *2016-03-12 08:19:15.936+0000: 1246: info : virNetClientNew:327 : RPC_CLIENT_NEW: client=0x7fed82bd8ca0 sock=0x7fed82bd8660* *2016-03-12 08:19:15.936+0000: 1246: info : virObjectRef:296 : OBJECT_REF: obj=0x7fed82bd8ca0* *2016-03-12 08:19:15.936+0000: 1246: info : virObjectRef:296 : OBJECT_REF: obj=0x7fed82bd8660* *2016-03-12 08:19:15.942+0000: 1244: debug : virNetClientIncomingEvent:1808 : client=0x7fed82bd8ca0 wantclose=0* *2016-03-12 08:19:15.942+0000: 1244: debug : virNetClientIncomingEvent:1816 : Event fired 0x7fed82bd8660 1* *2016-03-12 08:19:15.942+0000: 1244: debug : virNetMessageDecodeLength:151 : Got length, now need 36 total (32 more)* *2016-03-12 08:19:15.942+0000: 1244: info : virNetClientCallDispatch:1116 : RPC_CLIENT_MSG_RX: client=0x7fed82bd8ca0 len=36 prog=305402420 vers=1 proc=2 type=2 status=0 serial=1* *2016-03-12 08:19:15.942+0000: 1244: debug : virKeepAliveCheckMessage:377 : ka=(nil), client=0x7fed81fc5ed4, msg=0x7fed82bd8d08* *2016-03-12 08:19:15.942+0000: 1244: debug : virNetClientCallDispatchMessage:1008 : No program found for event with prog=305402420 vers=1* *2016-03-12 08:19:15.942+0000: 1244: debug : virNetMessageClear:57 : msg=0x7fed82bd8d08 nfds=0* *2016-03-12 08:19:15.942+0000: 1244: debug : virNetClientMarkClose:632 : client=0x7fed82bd8ca0, reason=0* *2016-03-12 08:19:15.942+0000: 1244: debug : virNetClientCloseLocked:648 : client=0x7fed82bd8ca0, sock=0x7fed82bd8660, reason=0* Here is the snapshot of code , virLXCMonitorPtr virLXCMonitorNew(virDomainObjPtr vm, const char *socketdir, virLXCMonitorCallbacksPtr cb) { virLXCMonitorPtr mon; char *sockpath = NULL; if (virLXCMonitorInitialize() < 0) return NULL; if (!(mon = virObjectLockableNew(virLXCMonitorClass))) return NULL; if (virAsprintf(&sockpath, "%s/%s.sock", socketdir, vm->def->name) < 0) goto error; if (!(mon->client = virNetClientNewUNIX(sockpath, false, NULL))) goto error; * if (virNetClientRegisterAsyncIO(mon->client) < 0)* * goto error;* * if (!(mon->program = virNetClientProgramNew(VIR_LXC_MONITOR_PROGRAM,* * VIR_LXC_MONITOR_PROGRAM_VERSION,* * virLXCMonitorEvents,* * ARRAY_CARDINALITY(virLXCMonitorEvents),* * mon)))* * goto error;* * if (virNetClientAddProgram(mon->client,* * mon->program) < 0)* * goto error;* * mon->vm = vm;* * memcpy(&mon->cb, cb, sizeof(mon->cb));* virObjectRef(mon); virNetClientSetCloseCallback(mon->client, virLXCMonitorEOFNotify, mon, virLXCMonitorCloseFreeCallback); Is the problem occurring due to invocation of “*virNetClientRegisterAsyncIO" api before the virNetClientAddProgram.Probably once we register for aysnc IO , immediately an event comes in and that thread takes priority and bails out since it does not find the client->prog?Also the client is not retrying to establish a new connection.* *Please let me any thoughts/comments.Is there any patch already available which has fixed this issue?We are using libvirt 1.2.15* *-Thanks,* *Rammohan*

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[libvirt-users] Questions regarding hostdev scsi
by Martin Polednik 18 Mar '16

18 Mar '16

Hi! I'm oVirt developer responsible for most of 'hostdev' support. While working on SCSI passthrough (that is hostdev type='scsi'), I've encountered few issues I'm not sure how to solve somewhat effectively and nicely. Just a note - oVirt by default disables 'dynamic_ownership', meaning we have to handle endpoint ownership/labeling ourselves. This is not something I can change in a short term. Also, oVirt uses libvirt's python API, I'll do my best using the original C names. To report and construct the hostdev element, I am using virConnectListAllNodeDevices. To get information about the devices, virNodeDeviceGetXMLDesc is called on each device. For PCI and USB devices, XML of the device contains everything needed to a) construct the element, b) fix endpoint permissions. SCSI device becomes more difficult as the information is scattered between multiple devices. Devices I have encountered contain this subtree: <device> <name>scsi_host4</name> <path>/sys/devices/pci0000:00/0000:00:1f.2/ata5/host4</path> <parent>pci_0000_00_1f_2</parent> <capability type='scsi_host'> <host>4</host> <unique_id>5</unique_id> </capability> </device> <device> <name>scsi_target4_0_0</name> <path>/sys/devices/pci0000:00/0000:00:1f.2/ata5/host4/target4:0:0</path> <parent>scsi_host4</parent> <capability type='scsi_target'> <target>target4:0:0</target> </capability> </device> <device> <name>scsi_4_0_0_0</name> <path>/sys/devices/pci0000:00/0000:00:1f.2/ata5/host4/target4:0:0/4:0:0:0</path> <parent>scsi_target4_0_0</parent> <driver> <name>sd</name> </driver> <capability type='scsi'> <host>4</host> <bus>0</bus> <target>0</target> <lun>0</lun> <type>disk</type> </capability> </device> <device> <name>block_sdb_Samsung_SSD_850_PRO_256GB_S251NXAGB42213R</name> <path>/sys/devices/pci0000:00/0000:00:1f.2/ata5/host4/target4:0:0/4:0:0:0/block/sdb</path> <parent>scsi_4_0_0_0</parent> <capability type='storage'> <block>/dev/sdb</block> <bus>ata</bus> <drive_type>disk</drive_type> <model>Samsung SSD 850</model> <vendor>ATA</vendor> <serial>Samsung_SSD_850_PRO_256GB_S251NXAGB42213R</serial> <size>256060514304</size> <logical_block_size>512</logical_block_size> <num_blocks>500118192</num_blocks> </capability> </device> <device> <name>scsi_generic_sg1</name> <path>/sys/devices/pci0000:00/0000:00:1f.2/ata5/host4/target4:0:0/4:0:0:0/scsi_generic/sg1</path> <parent>scsi_4_0_0_0</parent> <capability type='scsi_generic'> <char>/dev/sg1</char> </capability> </device> To construct the element, information from device scsi_4_0_0_0 is needed for <address> element (minus the host element). Adapter element is one of the places that I am not sure which information I can rely on, currently 'host' element from scsi_4_0_0_0 is used to form string 'scsi_host{host}'. Is this correct? Reliable? Whole different issue is locating the endpoint (/dev/sg{int}) to set the permissions. From the subtree, it's apparent that it is included in device called scsi_generic_sg1, but there is no *direct* link between scsi_4_0_0_0 and scsi_generic_sg1. At this point, we present user with devices matching capability='scsi', therefore to get the information 2 additional parses of the tree would have to be done. Other way would be reporting 'scsi_generic' capability, where only 2 additional virNodeDeviceLookupByName calls would be required (to descend 2 levels). Is there anything *really* wrong with this approach? Are there any other options without dynamic ownershit? Seclabel doesn't seem to be available. I'm thankful for any hints. Regards, mpolednik

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