- Users - libvirt List Archives

[libvirt-users] XML file format for snapshot-create
by Trey Dockendorf 13 Oct '11

13 Oct '11

I've created a very basic snapshot XML file, to allow for a description of the snapshot. However when running the virsh command, it doesn't like the formatting. # virsh snapshot-create proxy_0 /vmstore/proxy_0/proxy_0_ss.xml error: XML description for failed to parse snapshot xml document is not well formed or invalid This are the XML file contents... # cat proxy_0_ss.xml <domainsnapshot> <name></name> <description>Before updating to CR repo</desciption> </domainsnapshot> I'm running libvirt-0.8.7 on CentOS 6 x86_64. I can take snapshots just fine without defining the XML file, but I'd like to be able to add a description. Thanks - Trey

3 4

[libvirt-users] BIOS Delay
by xuteng 13 Oct '11

13 Oct '11

Hi, Does the libvirt support the bios delay ? I mean that after set a special number of seconds or minutes, when the domain starts, the bios will delay after the time I set Thanks for your time wade xuteng via foxmail

2 2

[libvirt-users] Live Migration using Libvirt migrate()
by PREETHI RAMESH 12 Oct '11

12 Oct '11

Hi, This is a follow up of the mail regd migration I'd posted a few days ago. My scenario: I'm creating two virtual machines images from an Ubuntu 10.10 iso of RAM size 128 and 700 MB. Using the migrate() , I migrate it from the current physical machine to the destination machine via a 100 Mbps switch LAN connection. BOTH migrations take the same amount of time. Checking out the eth0's transmitted and received bytes after and before the migration, I find that there's NO change in the readings. Using any other method to migrate(virsh,Qemu) takes a substantial amount of time(close to 10 seconds) for the 128 and 700 MB images. How can this drastic change in migration time be accounted for? Are there any other ways to check if the VM has been successfully migrated to the destination(i tried using virsh console after migrate() but for some reason it just hangs. I tried out the suggested patches on various sites but to no avail)? Is pinging the migrated VM from its PM a sure test for successful migration? Thanks guys.

2 1

[libvirt-users] Performance tuning questions for mail server
by Alex 11 Oct '11

11 Oct '11

Hi, I have a fedora15 x86_64 host with one fedora15 guest running amavis+spamassassin+postfix and performance is horrible. The host is a quad-core E13240 with 16GB and 3 1TB Seagate ST31000524NS and all partitions are ext4. I've allocated 4 processors and 8GB of RAM to this guest. I really hoped someone could help me identify areas in which performance can be improved at both the guest and host. Load on the server is regularly above 20, yet the processors generally are idle and the host is still responsive. Should the concentration of the performance tuning be done on the guest or the host? I've read through the information at http://libvirt.org/formatdomain.html#elementsMemoryTuning but I don't know how the settings apply to my configuration and which ones apply to my hardware. I've included my libvirt xml config below. It was built using virt-manager on fedora15. There appears to be quite a few other options that are available and not provided by virt-manager that I would like to be able to use. I've done a little kernel tuning on the host, although it doesn't appear to have made much difference. Are there a set of values for kernel parameters that would be advisable to make for a mail server? Here is what I currently have: # sysctl -p net.ipv4.ip_forward = 1 net.ipv4.conf.default.rp_filter = 1 net.ipv4.conf.default.accept_source_route = 0 kernel.sysrq = 0 kernel.core_uses_pid = 1 net.bridge.bridge-nf-call-ip6tables = 0 net.bridge.bridge-nf-call-iptables = 0 net.bridge.bridge-nf-call-arptables = 0 net.ipv4.ip_forward = 1 net.ipv4.conf.default.rp_filter = 0 net.ipv4.conf.all.send_redirects = 0 net.ipv4.conf.default.send_redirects = 0 net.ipv4.icmp_ignore_bogus_error_responses = 1 net.ipv4.conf.all.log_martians = 0 net.ipv4.conf.default.log_martians = 0 net.ipv4.conf.default.accept_source_route = 0 net.ipv4.conf.all.accept_redirects = 0 net.ipv4.conf.default.accept_redirects = 0 vm.vfs_cache_pressure = 35 vm.nr_hugepages = 512 net.ipv4.tcp_max_syn_backlog = 2048 fs.aio-max-nr = 1048576 vm.dirty_background_ratio = 3 vm.dirty_ratio = 40 After making changes, do you have any recommendations on which tools to use to monitor those changes and see how they perform? I have noatime set in fstab in the guest for the /var partition, where much of the spamassassin occurs. I've included below my libvirt xml config for the guest and hoped someone could make some recommendations on how to apply the cputune and memtune parameters to my system. <domain type='kvm'> <name>mail02</name> <uuid>ec4f3cf5-2f27-fb3e-72f6-3fa3176b13b6</uuid> <memory>8388608</memory> <currentMemory>8388608</currentMemory> <vcpu>8</vcpu> <os> <type arch='x86_64' machine='pc-0.14'>hvm</type> <boot dev='hd'/> </os> <features> <acpi/> <apic/> <pae/> </features> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>restart</on_crash> <devices> <emulator>/usr/bin/qemu-kvm</emulator> <disk type='file' device='disk'> <driver name='qemu' type='raw'/> <source file='/var/lib/libvirt/images/mail02.img'/> <target dev='vda' bus='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/> </disk> <disk type='block' device='cdrom'> <driver name='qemu' type='raw'/> <target dev='hdc' bus='ide'/> <readonly/> <address type='drive' controller='0' bus='1' unit='0'/> </disk> <controller type='ide' index='0'> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> </controller> <interface type='bridge'> <mac address='52:54:00:67:2c:4c'/> <source bridge='br0'/> <model type='virtio'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> <serial type='pty'> <target port='0'/> </serial> <console type='pty'> <target type='serial' port='0'/> </console> <input type='mouse' bus='ps2'/> <graphics type='vnc' port='-1' autoport='yes'/> <video> <model type='cirrus' vram='9216' heads='1'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/> </video> <memballoon model='virtio'> <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/> </memballoon> </devices> </domain> Thanks, Alex

5 17

Re: [libvirt-users] Libvirt newbie, need help with doubts
by Eric Blake 08 Oct '11

08 Oct '11

Forwarding to the list (this was mistakenly sent to just me) On 10/07/2011 11:32 AM, Mohammed Naser wrote: > On 2011-10-07, at 12:13 PM, Eric Blake<eblake(a)redhat.com> wrote: > >> On 10/07/2011 05:28 AM, PREETHI RAMESH wrote: >>> >>> 3. I'm developing an application in Java to monitor VM usage(Memory,CPU, >>> Network etc). Are there any easily integrable graph plotting applications I >>> could integrate with? >> >> Sorry, I can't answer this one. > > There is a plugin that collects resource details of libvirt for > collectd. I believe that collectd collects data in an RRD database and > I'm sure you can find an RRD charting library for Java. > >> >> -- >> Eric Blake eblake(a)redhat.com +1-801-349-2682 >> Libvirt virtualization library http://libvirt.org >> >> _______________________________________________ >> libvirt-users mailing list >> libvirt-users(a)redhat.com >> https://www.redhat.com/mailman/listinfo/libvirt-users > > Regards, > Mohammed Naser > > Sent from my iPhone -- Eric Blake eblake(a)redhat.com +1-801-349-2682 Libvirt virtualization library http://libvirt.org

1 0

[libvirt-users] Libvirt newbie, need help with doubts
by PREETHI RAMESH 08 Oct '11

08 Oct '11

Hi, These are my doubts: 1. I tried live migration of Ubuntu 11.04 from the one physical machine to another using the migrate() function. I connected via tcp in the destination URI and migrated successfully(lesser than 2 seconds). I tried running virsh list --all on the destination PM and confirmed that the VM had been migrated successfully. When I tried checking ps aux | grep vmname where vmname was the name of the VM migrated, I could see that on the source PM the thread was still active with the PID though the machine had been migrated successfully. Shouldn't the vmname not be listed at all on the source PM's side,if it has been completely migrated? Isn't 2 seconds too little(considering the memory allotted to the VM was 128MB and I'm using a 100Mbps LAN switch, time taken=size/speed~10 seconds). Why is virsh list --all showing me that the VM migrated to be shutdown on the source PM? If it's been completely migrated, shouldn't the entry be removed completely? 2. Is there any way to set the CPU limit in terms of % of CPU used on a VCPU using libvirt function? As in, if I want my VM to use just 10% of VCPU 1. 3. I'm developing an application in Java to monitor VM usage(Memory,CPU, Network etc). Are there any easily integrable graph plotting applications I could integrate with? Thanks for your time. Regards, Preethi

2 1

[libvirt-users] Reg: shutdown/restart from within the container(system LXC)
by Alphonse Hansel Anthony 07 Oct '11

07 Oct '11

Hi, Is it possible to shutdown/restart a system LXC from within the container? From what I have observed(Version - 0.8.4): * The libvirt_lxc manager process, which listens on the /dev/pts for console connection loops infinitely. Let me know If I am missing out something obvious or there exists any other way to shutdown/restart system LXC from within. Any pointers in this regard would be useful. Thanks, Alphonse

2 2

[libvirt-users] Libvirt for custom VM
by ankur deshwal 07 Oct '11

07 Oct '11

Hi, I need to create an application where I can use a single interface for different VMs (libvirt becomes an obvious choice then). However I will need to control a VM running on custom hypervisor other than ones currently supported by libvirt. Is it possible to add a new interface to the hypervisor (easily)? Shall I try to use "test-hypervisor" supported by libvirt ?? I shall be grateful for some initial pointers to read which can help me for the task. Thanks and Regards, Ankur

2 1

[libvirt-users] Need help debugging virtio net issue
by Darren Dao 06 Oct '11

06 Oct '11

This is what I use for creating the VM sudo virt-install -n myvm -r 2048 --vcpus=1 --accelerate -v -w bridge:br0,model=virtio --nographics -m 54:52:00:01:bb:8d --disk path=/storage_pool/myvm.raw,size=20,bus=virtio --pxe It used to work fine, but now it get stuck trying to do pxeboot/kickstart. Here's what I see when trying to debug the pxeboot/kickstart process: * Querying DHCP server for IP address went through fine * vmlinuz.CentOS5-5.5-x86_64 was downloaded successfully * initrd.img.CentOS5-5.5-x86_64 started to get transferred, but then stopped. It looks like the VM's network interface just crashed (can't even ping the VM anymore) If I don't use virtio for networking, then everything went through fine. What's strange that is virtio used to work fine. I ran out of ideas/ways to debug this issue. Any has any idea? Here's more info on my system: Host: * Scientific Linux 6, kernel version: 2.6.32-71.el6.x86_64 * libvirt: 0.8.1-27 * qemu-kvm: 0.12.1.2-2.113 Guest: * Scientific Linux 6, kernel version: 2.6.32-71.el6.x86_64

1 0

[libvirt-users] libvir: Remote error : cannot recv data: : Connection reset by peer
by PREETHI RAMESH 05 Oct '11

05 Oct '11

I'm using Libvirt's Java API and connecting to the hypervisor using the same. My program is such that periodic discovery of active VMs is done using Libvirt's functions. However, when I try to perform any VM related operations while the Java code connecting to Qemu is running such as shutdown, start VM using virsh, I end up with : 'libvir: Remote error : cannot recv data: : Connection reset by peer' on my Java IDE and 'error: cannot recv data: : Connection reset by peer error: failed to connect to the hypervisor' on the terminal running virsh. I'm using QEMU emulator version 0.14.0 (qemu-kvm-0.14.0) and Libvirt version 0.4.7 on Ubuntu 11.04. Please help me out! Thanks.

3 2