- Users - libvirt List Archives

[libvirt-users] Live migration process in src/qemu_driver.ca
by Faizul Bari 20 Mar '14

20 Mar '14

Hello, I have been trying to track different phases of a live migration process. I am using libvirt with qemu-kvm. I am issuing migration commands using virsh. Now, I want to measure the time spent in each phase of live migration, e.g., pre-copy and stop-copy. I stumbled upon the file qemu_driver.c. It has functions like qemudDomainMigratePrepare2 qemudDomainMigratePerform qemudDomainMigrateFinish2 I want to know whether qemudDomainMigratePerform and qemudDomainMigrateFinish2 directly map to the pre-copy and stop-copy phase? or the qemudDomainMigratePerform function performs both of them? Any pointers or suggestions will be greatly appreciated. Regards ---------------------- Md. Faizul Bari PhD Student David R. Cheriton School of Computer Science University of Waterloo {http://www.cs.uwaterloo.ca/~mfbari} [My mind rebels at stagnation! Give me problems! Give me work!]

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[libvirt-users] Linux host / Windows guest sharing
by Pal, Laszlo 20 Mar '14

20 Mar '14

Hi, I'm almost give up again because for a day I try to access my windows kvm guest from FC20 :) I've tried everything including virtio mapping mount -t 9p -o trans=virtio,version=9p2000.L hostshare /tmp/hostfiles where I get the following messages mount: special device hostshare does not exist --- --- to be honest clipboard sharing would be enough for me, so I googled why it is not working and I applied this: https://mytechdepot.wordpress.com/2013/02/22/enabling-clipboard-copy-paste-… yum install spice-vdagent # chkconfig --add spice-vdagentd # service spice-vdagentd start but, the clipboard sharing isn't working.... Do you have any idea to solve any of the issues above? Thank you Vlad

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[libvirt-users] Adjust disk image migration (NBD)
by Joaquim Barrera 20 Mar '14

20 Mar '14

Hi all, As I am doing some tests with qemu, I realized that the way it does 'migrate -i tcp:DEST:444' is not the same as 'libvirt migrate --copy-storage-inc'. Basically qemu uses the same stream as RAM migration and libvirt takes advantage of NBD transfer. With virsh migrate-setspeed I observed that one can only control the transfer throughput of RAM, but not disk synchronization. At least this is what I can see in bmon when doing a migration with incremental copy. The question is: Am I missing something or it is not implemented? Thank you guys!

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[libvirt-users] KVM networking help needed - Promiscuous network configuration for guest Snort instance
by Philip Wang 18 Mar '14

18 Mar '14

Hi, I am looking for some direction on how to configure KVM networking so that a promiscuous bridge/host nic/guest nic allows two different network monitoring packages to sniff the same physical traffic. The idea is to run a commercial package on the CentOS 6.5 host and Snort, via Security Onion, on the guest, both being fed by a physical switch SPAN or physical firewall TAP. The host has two NICs, one for management and one for sniffing. I am using libvirt and libvirt-manager to supplement configuration. I have basic bridge networking configured and connected on the management NIC, but I can't seem to figure out the missing piece for getting physical network traffic from the SPAN/TAP port to the Xubuntu guest NIC for sniffing. I have seen mention of setting the bridge aging time to 0, but that did not seem to work and the only place I could find to verify the setting was by running brctl showmacs <brisge name>. I have also seen posts saying this was more of a workaround, without discussing an alternate method. I have tinkered with setting the host nic, bridge, and guest nic to promiscuous mode, only to see relatively equal traffic climb on the host nic and bridge, but not the guest nic. Other searched have turned up discussions about tunctl and its implementation, so at this point I figured a reality check was in order. Is this idea feasible? If so, where should I be looking for information on how to implement it? Thanks in advance for any pointers.

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[libvirt-users] Working Set Size Estimation
by Giampiero De Ciantis 18 Mar '14

18 Mar '14

Is there a way through virsh or libvirt to get the working set size for a VM. I am trying to find a metric similar to what VMware calls "Active Memory". Thanks in advance, -Gp

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[libvirt-users] KVM -snapshot mode
by chris 0 18 Mar '14

18 Mar '14

Hi, I'm just wondering is there any way for me to trigger KVM's -snapshot parameter from libvirt. I don't want to clone a disk etc. I just need a way so that KVM is spawned with a '-snapshot' parameter. Anyone got any ideas? Cheers Chris

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[libvirt-users] Undoing domiftune changes
by Brian Rak 18 Mar '14

18 Mar '14

If I apply some network limits with domiftune, how do I undo them (without restarting the VM?) So let's say I did: # virsh domiftune SRVID8736 vnet0 inbound.average: 0 inbound.peak : 0 inbound.burst : 0 outbound.average: 0 outbound.peak : 0 outbound.burst : 0 # virsh domiftune SRVID8736 vnet0 --outbound 1000,1000,1000 How I do revert this back to what it was before I set it? If I try "--outbound 0,0,0" it fails, saying "error: outbound average is mandatory"

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[libvirt-users] a question on vCPU setting for lxc
by WANG Cheng D 18 Mar '14

18 Mar '14

Dear all, I am not clear about the 'vcpu' element for CPU allocation. I allocated 1 vCPU to my container, after I started the container, I ran 4 computation-intensive tasks on the container. And I found all the 4 physical core are 100% used (my host has 4 physical cores and no other application ran on the host except the container). That is, all available cores were used by the container. I want to know how to give a hard limitation for CPU usage of a container. So I don't understand what 'vcpu' setting can be used for. I know that another CPU allocation element 'shares' can also be used, but this elements only give a relative quota. If new containers are started, the CPU quota for the already started containers will change. Regards, Cheng

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[libvirt-users] Sys::Virt integration into other event loops
by Scott Wiersdorf 17 Mar '14

17 Mar '14

Hi all, I’m trying to integrate Perl’s Sys::Virt into an already existing AnyEvent program. I’m accustomed to writing things like this: use EV; use AnyEvent; use AnyEvent::Handle; my $h = AnyEvent::Handle->new(fh => $fh, …); $h->on_read(sub { … }); EV::run; ## start the event loop I can add some code in the on_read() handler and every time the $fh has something to read, it will fire off. I’d like to do something similar with Sys::Virt, but I can’t seem to wrap my head around its event system. The only examples I can find are the ones included in Sys::Virt source, which consist of a series of run_once() calls, or a while loop around run_default(). Does anyone have any idea how I can make this play nicely with an existing event loop such as EV, or even to fire off ($cv->send) an AnyEvent condvar when the event I set in domain_event_register_any() triggers? Our current solution involves setting an AnyEvent->timer, which periodically fires off and then does a run_once() to see if any events happened during the period, but we’d like something more responsive (i.e., triggers when the event actually occurs) and less poll-y feeling. I’d appreciate any advice you may have—thanks! Scott

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[libvirt-users] Problem in getting memory statistics
by Pasquale Dir 17 Mar '14

17 Mar '14

Hello, I need to get how much memory is used by a guest system, in order to implement some monitoring function which tells me if the system is overstressed. I am currently using java apis and the binding which was suggested to me was Domain.memoryStats(); This is a binding to int virDomainMemoryStats (virDomainPtr<http://libvirt.org/html/libvirt-libvirt.html#virDomainPtr>dom, virDomainMemoryStatPtr<http://libvirt.org/html/libvirt-libvirt.html#virDomainMemoryStatPtr>stats, unsigned int nr_stats, unsigned int flags). Problem is that it returns me just tags 0,6 and 7. Looking at the documentation I see they are not what I am looking for...I would rather need 4 (VIR_DOMAIN_MEMORY_STAT_UNUSED) and 5 (VIR_DOMAIN_MEMORY_STAT_AVAILABLE). Is there a way to set them?

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