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11

If you don't want to do any configuration inside the guest, then the only option is a DHCP server that hands out static IP addresses. If you use bridge mode, that will probably be some external DHCP server. Consult its manual to find out how to serve static leases. But at least in forward modes nat or route, you could use libvirt's built-in 'dnsmasq' (More ...


11

TRIM works at the filesystem level so as you're giving your KVM domains a raw block device then you need to enable TRIM from within the domain; your host can't know the domains filesystem utilisation without examining it. To enable this you need to ensure there's a discard='unmap' attribute added to the disk definition in the XML for the domain, this is ...


8

You can't use switch port security on the Cisco since all the VMs will be sharing a physical switch port. And you can't use Linux iptables because the traffic is being bridged, not routed, through the hypervisor machine. But you can emulate switch port security on the hypervisor with Linux ebtables, which is a lesser-known layer 2/3 firewall on the Linux ...


6

While it might not look like one, Hyper-V actually is a type-1 hypervisor, because the virtualization layer is placed below the Windows operating system and mediates all hardware access (some time ago, before hardware-assisted virtualization improved a lot, it was very common to experience really slow graphic performance on Hyper-V hosts, due to the O.S. ...


6

This is for google guys like me. Those answers are pretty useless, this is not a distro problem but a bug in Windows: http://keyliner.blogspot.se/2009/11/windows-7-slow-keyboard-response.html (second clause) That is what helped me: a. Start, Run, "Regedit" If the RUN command is not visible, see this link. b. Tunnel to this key: ...


5

This is how I currently do installs of Windows with virtio drivers at install: Create the new VM with a genuine Windows installation ISO image. I cannot guarantee that anything will work if you use a pirated copy of Windows. Choose to customize the machine configuration before install. Select the IDE hard drive, and change its type to VirtIO. Click ...


4

You can, but you probably shouldn't. The DL360 G7 doesn't present disks in a JBOD fashion. If you're using the onboard HP Smart Array controller, this won't work the way you expect. Depending on the OS you use, there are swap and other I/O activity considerations. Why go through all of this? If you want ZFS, just use it on the server in a baremetal OS ...


4

No, it doesn't work like that. Among the reasons is that for a single thread, you can never get more than the 2 GHz clock speed one single core offers and virtualization is no trick around this fundamental restriction.


4

When the user's home directory is encrypted with ecryptfs sshd cannot read the authorized_keys file from the user's home directory before the home directory has been mounted. During login sshd will use pam to authenticate the user, and pam will use the password entered by the user to mount the encrypted home directory. This is problematic if you want to ...


4

So I'm managed to run the nested Hypervisor inside KVM and it turns out to me that the Red Hat Kernel 2.6.32 did not support the nested keyword when it was passed using kvm-intel.nested=1 so that is the reason there was no file such as /sys/module/kvm_intel/parameters/nested It worked for me in kernel 3.10 I installed it set the nested parameter. ...


4

The Problem I've got the same problem and I haven't found a good solution. Here's what I found: The problem is that after resume, the system and hardware clock times on the guest are different: root@guest:~# date; hwclock Sat Oct 11 13:09:38 UTC 2014 Sat Oct 11 13:10:42 2014 -0.454380 seconds On the host, they agree: root@four:~# date; hwclock Sat ...


3

As you are using Openstack, when you create a flavour you can specify the rxtx_factor. My understanding is that this is used to calculate a percentage of the rtx_cap on the network that is available to the VM. I'm not sure if all hypervisors will support it however, though so you may need to do some additional digging to see if KVM does.


3

virt-sparsify can do all this with less hassle on your part: http://libguestfs.org/virt-sparsify.1.html


3

I got so inspired by kasperd's idea yesterday that I made this: https://github.com/bjornnorman/decryptfs-ssh I've tried it out a little already and it seems to work brilliantly. It makes it really simple to add/remove keys for passwordless decryption of ecryptfs home folders when using SSH... Like kasperd's original, it hasn't been exposed to a peer ...


3

You need to specify a valid URI for the migration to be successful. What kind of transport is available depends on your setup, but try qemu+ssh://10.8.1.9.


3

Set the wanted disk as virtio-disk0, with target of /dev/vda. The order the disks appear in, in the XML is also important, so make sure the OS disk comes first


3

After verifying base guest configuration file (xml) found the problem. <vcpu placement='static' cpuset='2'>1</vcpu> Since I used same template for creating all VMs after cloning, all VMs were using same CPU.


3

On my RHEL6 and CentOS6 that is established by creating a symbolic link to VM XML description in /etc/libvirt/qemu/autostart/ : ls -la /etc/libvirt/qemu/autostart/ total 4 drwxr-xr-x. 2 root root 4096 Dec 19 2012 . drwx------. 4 root root 4096 Dec 21 08:50 .. lrwxrwxrwx. 1 root root 29 Mar 3 2012 hosting2.xml -> ../hosting2.xml lrwxrwxrwx. 1 root ...


3

To change the state of the network link for a KVM guest it would be much better to use the appropriate tool, i.e. the hypervisor virsh domif-setlink domain interface-device state Modify link state of the domain’s virtual interface. Possible values for state are "up" and "down". If --config is specified, only the persistent configuration of the ...


3

Is it safe to boot Linux from a USB drive? Yes, why not? I do it regularly. But having said that, it's not entirely trivial to do it well. If you just straight install Linux to a USB disk it's usually really slow and doesn't really work that great. However, if you use a tool like unetbootin it'll create a more optimal installation with which you can ...


3

Define "safe". As in: Does the system boot from USB? Yes Data integrity? No Fault tolerance? No I would not trust a file server to be booted from a single USB pen, unless it's a server just for testing/lab etc. We use USB drives (expensive ones) in our vSphere Cluster, and I've encountered failures many times. You've indicated that you have replaced the ...


3

-device e1000,netdev=hostnet0 This. Switch to virtio_net before you try anything else. step two: try to play with the NIC offload settings using ethtool -K turn off TSO, LSO, LRO, see if you get different results. step three: try a different distro. Ubuntu is notorious for KVM related bugs, so switch to CentOS or even Fedora as a test.


3

Check that your VMs have ip addresses on 10.x.x.x/24 (netmask 255.255.255.0) Set 10.x.x.11 (br0 ip address) as the default gateway of your VMs Enable ip forwarding on the physical host Enable SNAT with: iptables -t nat -A POSTROUTING -s 10.x.x.x/24 -o eth1 -j SNAT --to y.y.y.102


3

You may be overthinking this. The manual assignment of cores here could actually result in lower performance. In the VMware world, we don't do this unless there are very specific requirements, but for the workload and applications you've described, it's not necessary. Let KVM schedule things and be done. If in doubt, get more cores and sockets. But CPU ...


2

Assuming you were using replica 3, when 2 hosts go down the file system becomes read-only and this could explain what you currently see to some degree. In most cases we should expect the VM to freeze as qemu cannot write to the storage, but I need some more information about it so log files from the hosts are needed here. First of all let's see that the ...


2

You appear to be attempting to install using a serial console, rather than a normal console. Not sure why you're doing that, but... By default the installer tries to display either text or graphics on the Linux console. To divert output to the serial console you need to hit Tab at the boot screen, and ensure that you add the following options to the boot ...


2

cache=none is probably not a good idea when you're using qcow2 files. A qcow2 file makes it appear that every access to the disk is fragmented. This means you get the random access performance of the drive every time and some flash drives are awefully slow (spelling intended) at random writes. Try with cache=unsafe (temporarily) to confirm this is the ...


2

Qcow2 file backend can be significantly slow with cache=none setting. Moreover, "-o prellocation=metadata" preallocate metadata only, and actual file data will be fragmented. In other words, the qcow2 file remain a sparse one with only short stroke of allocation (for metadata). In the past a "-o preallocation=full" option appeared, by in recent qemu-img ...


2

Define the bridge interface with eth0 as port Set the IP address on the bridge interface You will need the bridge-utils package installed (most likely is already there). Here's how you would configure this in /etc/network/interfaces. Restart the network service (or reboot the machine) auto lo iface lo inet loopback auto eth0 iface eth0 inet manual ...



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