virt

virt@lists.centos.org

1608 discussions

Reading the new 6.0 manual - now questions
by Steve Campbell 20 Jun '11

20 Jun '11

I'm new to running VMs, so I'm hoping this hasn't been a problem question asked before. I've only glazed over the emails from this list since I've joined due to not really needing all of the great information if provides. Eric suggested I wait for Centos 6 to start loading my new VM host, and so I grabbed the RH Virtualization PDF and started digging in. Firstly, it occurred to me that Centos 6 might not provide the virtualization rpms like it did with Centos 5. RH makes this an add-on to their license. Does anyone know if the upcoming Centos 6 will provide the virtualization packages (right away or in the future)? Secondly, I'm not sure I understand the CPU allocation stuff. If I have 6 cores, it appears I can only create VMs that use 6 cores total. Using the GUI for creating a new VM will provide me with a max number I can allocate. Does this mean that I can allocate, for example, 3 VMs that use 2 cores each and never be able to create any other new VMs or does this mean I can create as many VMs as I want but only start VMs that use the max total cores or less? I should get my shiny new machine next week, the one with real virtualization capability, so some of this may be answered on my own by playing around, but until then, thought I'd get a head start on rectifying my stupidity. Thanks for any help (along with a special thanks to Eric for his original help). steve campbell

5 4

no virtual network until vnc connection
by gisto85 16 Jun '11

16 Jun '11

Hi, I have a host with 3 guests ( 2 CentOs 1 Windows 2003 ) If I shutdown or reboot host the virtual machines starts up with no problems, If I pull down power supply when power come back host regulary startup, the vm startup ( autostart ) but vm machines network doesn't works until I connect to vm console ( e.g.: vncviewer 192.168.2.X:2 ) The host is "hp proliant ml350 g5" with network bonding (fault tolerance) CentOs 5.6, I have another identical server with 2 centos machines and no problem in case of power fault, when power come back the vm network start regulary. I attach some configuration files. Thanks in advance Egidio

1 0

My CentOS in VMware can't find my wireless card
by liming wu 16 Jun '11

16 Jun '11

hi, i'm woo, I'm a newer to CentOS. I installed my CentOS5.3(2.6.18-128.el5) in VMware. And my wireless card is MERCURY 54U(Atheros AR5xxx).I plugged the USB card into my virtual machine, but it couldn't be found. I've tried two drivers in different time: 1)install ath5k: -------------------------------------------------------------------------------- [root@wulmcent ~]# lsmod |grep ath5k [root@wulmcent ~]# modprobe ath5k [root@wulmcent ~]# lsmod |grep ath5k ath5k 97001 0 mac80211 137545 1 ath5k cfg80211 30793 2 ath5k,mac80211 [root@wulmcent ~]# ifconfig eth0 Link encap:Ethernet HWaddr 00:0C:29:F5:3D:F3 inet addr:172.3.0.5 Bcast:172.3.0.255 Mask:255.255.255.0 inet6 addr: fe80::20c:29ff:fef5:3df3/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:16417 errors:0 dropped:0 overruns:0 frame:0 TX packets:1434 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:1311085 (1.2 MiB) TX bytes:211106 (206.1 KiB) Interrupt:67 Base address:0x2000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:224 errors:0 dropped:0 overruns:0 frame:0 TX packets:224 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:15568 (15.2 KiB) TX bytes:15568 (15.2 KiB) [root@wulmcent ~]# -------------------------------------------------------------------------------- 2)install madwifi(0.9.4) -------------------------------------------------------------------------------- [root@wulmcent madwifi-0.9.4]# modprobe ath_pci [root@wulmcent madwifi-0.9.4]# lsmod|grep ath_pci ath_pci 88868 0 wlan 181904 1 ath_pci ath_hal 195536 1 ath_pci [root@wulmcent madwifi-0.9.4]# ifconfig eth0 Link encap:Ethernet HWaddr 00:0C:29:F5:3D:F3 inet addr:172.3.0.5 Bcast:172.3.0.255 Mask:255.255.255.0 inet6 addr: fe80::20c:29ff:fef5:3df3/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:17055 errors:0 dropped:0 overruns:0 frame:0 TX packets:1663 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:1369453 (1.3 MiB) TX bytes:239700 (234.0 KiB) Interrupt:67 Base address:0x2000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:224 errors:0 dropped:0 overruns:0 frame:0 TX packets:224 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:15568 (15.2 KiB) TX bytes:15568 (15.2 KiB) [root@wulmcent madwifi-0.9.4]# dmesg |grep ath5k [root@wulmcent madwifi-0.9.4]# dmesg |grep ath device-mapper: multipath: version 1.0.5 loaded ath_hal: module license 'Proprietary' taints kernel. ath_hal: 0.9.18.0 (AR5210, AR5211, AR5212, RF5111, RF5112, RF2413, RF5413) ath_pci: 0.9.4 -------------------------------------------------------------------------------- As the message displayed above, my system didn't find my wireless card. I don't know what to do to fix it. I need your help, thank you! ==== woo

4 8

Drupal/MySQL performance in Xen and OpenVZ
by Einar S. Idsø 08 Jun '11

08 Jun '11

Hi, We are considering a transition from OpenVZ to Xen for our web server infrastructure. The primary task performed by the virtual servers is to run a number of Drupal sites with a MySQL backend. The webserver and MySQL servers are on separate virtual hosts. We also have a number of smaller hosts running on the same hardware (a couple of dev-servers, a logging-and-monitoring server, a secondary webserver ++). >From what I have understood, there is very little performance degradation in OpenVZ, also for IO operations, due to the use of isolated containers instead of actual virtualisation. I have also seen tests indicating detrimental IO performance of Xen IO [1]. Despite this, I have found several posters [2] suggesting the use of Xen over OpenVZ when it comes to running Drupal sites. One of the main arguments against OpenVZ is unpredictable and variable performance because VPS-hosts tend to overbook their host capacitiy. This is not an issue for us since we host our own VPSs on our own hardware so we are in complete control. So: Is there any reason Xen may be able to outperform OpenVZ for the webserver-setup I have described, or should I just continue to use OpenVZ? Cheers, Einar Sources: [1] http://www.ilsistemista.net/index.php/virtualization/1-virtual-machines-per… [2] http://2bits.com/articles/hosting-virtualization-openvz-vs-xen-which-is-bes…

2 3

Confused by "qemu-img convert"
by MargoAndTodd 07 Jun '11

07 Jun '11

> Hi All, > > Okay. Now I am confused. > > I have a bunch of virtual machines running under Virtual Box 3.2.12. > I want to run them under KVM and drop Virtual Box from these > systems. > > Supposedly "qemu-img convert" now supports direct conversion > from vdi to whatever KVM uses. So I fired up the man page and > got really confused. Then I fired up Google and got worse > confused. > > Might I impose on some kind individual to write down a sample > run string that would show me how to do this? > > Many thanks, > -T > Is it as easy as? qemu-img convert -f vdi oldImage.vdi -O qcow2 newImage.qcow Do I need a ton of disk space to go to a full hard drive then back to a small virtual hard drive? Do I need the Virtual Box XML file for anything or just the VDI? Many thanks, -T

2 3

wrong kvm vm status in libvirt
by franco battiato 27 May '11

27 May '11

Hi, are some days that i'm searching for a possible bug in libvirt. I use Solusvm control panel to manage my kvm VM. If i start a vm it will be shown correctly as Running. After some days i found that libvirt show same vm as shut off, but this is not true. I still see login to vm, join in ssh, join in vnc etc. If i want to show correct state i need to power off the VM and boot it again. this is an example: # list --all Id Name State ---------------------------------- 18 kvm160 running - kvm134 shut off - kvm139 shut off - kvm140 shut off - kvm144 shut off - kvm147 shut off - kvm148 shut off this is not true because all vm are running. For example the kvm134: ]# ps ax|grep kvm134 8313 ? Sl 3671:51 /usr/libexec/qemu-kvm -S -M rhel5.4.0 -m 1536 -smp 1,sockets=1,cores=1,threads=1 -name kvm134 -uuid f74f0b83-854a-b22f-36bd-a5ee906926e3 -monitor unix:/var/lib/libvirt/qemu/kvm134.monitor,server,nowait -no-kvm-pit-reinjection -boot cd -drive file=/dev/vps/kvm134_img,if=ide,bus=0,unit=0,boot=on,format=raw -drive file=/home/solusvm/kvm/iso/CentOS-5.5-x86_64-bin-DVD.iso,if=ide,media=cdrom,bus=1,unit=0,readonly=on,format=raw -net nic,macaddr=00:16:3b:0c:a1:a5,vlan=0,model=e1000 -net tap,fd=17,vlan=0 -net nic,macaddr=00:18:3a:4c:b7:85,vlan=1,model=e1000 -net tap,fd=19,vlan=1 -serial none -parallel none -usb -usbdevice tablet -vnc 0.0.0.0:8,password -vga cirrus -balloon virtio as you can see the vm is working well. Have someone shown same issue? if i enable debug i see that libvirt try to start vm but see the bridge resource busy (this is normal because vm is already running). Versions: Centos 5.6 x86_64 Compiled against library: libvir 0.8.2 Using library: libvir 0.8.2 Using API: QEMU 0.8.2 Running hypervisor: QEMU 0.9.1 Regards

1 0

nwfilter broke on 5.6?
by Steve Shorter 25 May '11

25 May '11

Howdy! I have virtual domains running under libvirt. I have a valid xml definition and it starts fine, except when I add the filterref line as below <interface type='bridge'> <mac address='54:52:00:44:36:d7'/> <source bridge='vlan50'/> <target dev='guest_if0'/> <model type='virtio'/> <filterref filter='clean-traffic'/> </interface> [root@kvm1 qemu]# virsh start centos56_img error: Failed to start domain centos56_img error: internal error Could not get access to ACL tech driver 'ebiptables' [root@kvm1 qemu]# lsmod|grep table ebtables 53441 0 iptable_filter 36161 0 ip_tables 55329 1 iptable_filter x_tables 50505 1 ip_tables Is there a module missing 'ebiptables' or is it misnamed or some other problem? thanx - steve

1 0

kvm guest ram
by Markus Falb 24 May '11

24 May '11

Hi, On a 4gb 64 bit centos kvm guest per libvirt <memory>4194304</memory> <currentMemory>4194304</currentMemory> but in dmesg of the guest I find Memory: 4039712k/5242880k available (2592k kernel code, 154076k reserved, 1653k data, 224k init) Why is dmesg reporting 5g of ram ? Or am I reading wrong ? How much memory on the Host is necessary on the kvm host for this "4g" machine in the worst case (I try to not overcommit for now). I want to avoid the situation that this "4g" machine requires "5g". A 4gb 32 bit machine is reporting expected values Memory: 3102712k/4194304k available (2190k kernel code, 41592k reserved, 911k data, 228k init, 2228160k highmem) All of the above lead to the following more generic question: How many percent of the Host RAM may I safely give to guests (without overcommiting) ? -- Kind Regards, Markus Falb

1 0

KVM vs ESXi
by Drew 18 May '11

18 May '11

Morning Everyone, I'm busy doing a rebuild of my home server and am tossing between VMware and KVM for this build. I already have experience with ESX, we use it at work, but I'm debating trying out KVM for a while. The server itself is a budget build using a Supermicro X8SAX board w/ i7-950 & 12GB RAM, LSI 3081 SAS RAID (1068e based), rolled into a NorcoTek 16 Bay SAS case. Not fancy but also decent enough for home use. I don't expect high performance out of this unit so unless the gear is hopelessly outclassed, I'm not in a position to entertain upgrading. Right now forking over $1000-$1500 on a $2000 system for a pair of higher end LSI/3ware/Acreca controller just isn't in the budget. ;-) My question to everyone are these: -How well does KVM support Windows Guests? I'm already running a Server 2008r2 and WHS 2011 (based on 08r2) machines at home which I want to consolidate into this box. -Does KVM have a concept of virtual switches and and are they tied to physical NICs? ESXi allows me to create a vSwitch that isn't tied to a physical NIC so I can create a DMZ that exists solely within the host system. I'd like to replicate that if possible. I know these are probably questions that I could answer on my own by RTFM but I have already, and never really got the answers I needed. Pretty much every how-to assumed I'd be doing basic stuff and not dabbling with advanced stuff. I also know that what's written doesn't always match what's in the field and you folks are the field. And with CentOS 6 just around the corner (no flame wars please, my nomex pants are at the cleaners :-P ) I'm wanting to know if it's worth holding off another month or so on finalizing my build. Thanks, -- Drew "Nothing in life is to be feared. It is only to be understood." --Marie Curie

3 2

Discover what vnet is attached to a kvm guest
by carlopmart 13 May '11

13 May '11

Hi all, How can I see what vnet is attached to a certain kvm guest?? For example: I have a kvmguest1. When I launch this guest with virsh command, virsh creates a new vnetX interface for this guest. How can I extract this virtual net interface (vnet0, vnet1, vnet2 or so on) using a script?? Thanks. -- CL Martinez carlopmart {at} gmail {d0t} com

3 3

Jump to page:

2025

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

virt