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2

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.


-1

You can't do this with KVM itself. You'd need some external software running to do it.


0

You say this is a server. Have you asked your provider? It's very possible that your provider is limiting you to a single MAC address per port.


1

You don't need to be messing with <memtune><hard_limit>. This is actually a rather dangerous setting when applied to KVM guests. I would remove that section immediately. However, users of QEMU and KVM are strongly advised not to set this limit as domain may get killed by the kernel if the guess is too low. To determine the memory needed for a ...


0

As far as I know, you can not access CPU's virtualization extension without a kernel driver. VirtualBox might be a better answer to your situation. VirtualBox can make use of CPU's virtualization extension, so it's faster than plain QEMU, easier to use as well. So try to persuade your customers' IT department to install VirtualBox on their machines.


0

Yes, you need to use virsh blockresize to notify the guest of the change. The syntax should be something like: virsh blockresize INSTANCE_NAME --path /dev/vg/guest --size NEWSIZEG


1

Your KVM instances should be able to saturate your hosts network connection with no issues. My first recommendation here is to upgrade both the host and guest's kernel. The stock CentOS 6.5 kernel does not have great performance for KVM. I'd suggest kernel-lt from ELRepo (or kernel-ml if you're feeling brave). This should give you a decent boost in ...


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 ...


0

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


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 ...


0

PXE booting VMs works perfectly well over bridged networks, just make sure your version of qemu comes with gPXE or iPXE, the old etherboot has some problems with certain DHCP servers (especially MS based DHCP).


0

If you're using libvirt, you can't do this in the virt-manager GUI, you have to edit the network XML directly, e.g. with virsh net-edit <networkname> You need to add a <tftp> element to set up a TFTP server (if you don't already have one), and add a <bootp> element inside the <dhcp> element of the configuration to tell clients about ...


1

Old question, I know. But to answer anyway: you cannot have two default gateways. That's where the RTNETLINK answers: File exists error comes from when issuing ifdown and ifup. Remove the gateway 10.10.20.1 line from either eth0 or eth1. And more general: /etc/init.d/networking restart or service networking restart were never really supported and are not ...


1

All of the "extra" rules you are seeing were added by the libvirt daemon to support (and secure) virtual networking for your virtual machine guests. You generally do not need to worry about these rules (and should not try to persist them, as then they would be duplicated at next boot). It's also clear that all of your persistent firewall rules were added to ...


0

Did you check in /etc/network/interfaces for "pre-up" directive, which may look something like: pre-up iptables-restore < /etc/iptables.rules Another possibility on Ubuntu/Debian is that scripts are located in /etc/network/if-pre-up.d/ directory, so you should list the contents of that dir: # ls -al /etc/network/if-pre-up.d/ Another possibility is ...


0

I think you are missing a iptable rule for the masquerade iptables -t nat -A POSTROUTING -s 10.0.0.0/24 -o eth0 -j MASQUERADE


-1

virt-v2v doesn't cover hyper-v. What you need is virt-p2v and treat the original hyper-v based VM as a physical machine.


1

I'm sure you can have a performance gain if you pin each VM to specific CPU cores, as well as restrict the hypervisor to one or two other cores. That would allow your VM's to optimally benefit from the L1 and L2 caches which are CPU specific and they won't be bothered by interrupts from NIC's and storage controllers. On the other hand I expect the ...


1

Yes, that is possible. You just need to use a tool like virt-v2v to make the image conversion. Additionally, if you google "convert hyper-v to rhel kvm" you'll find many tutorials.


1

CPU pinning ensures a VM will only get CPU time from a specific CPU or set of CPUs. Unless you have a very specific reason to pin, there usually is no need to do that.


1

Apparently, if you set cache=NONE for a disk image file on any host filesystem that does not support Direct IO, Virt-Manager will currently give a not very helpful error message saying "Something something... Invalid Argument" and refuse to start the Guest VM. One example of such a filesystem --that does not support Direct IO-- is the tmpfs. Another such ...


0

This is not really worthy of being called an answer but ... in case anyone else has the same problem. I can't explain it but the problem was solved by moving to different KVM host on different hardware but I don't think it was a real hardware problem. We have two servers. A Cisco which has 2 quad core procs. Linux shows 16 cpus. I guess that's with ...


2

As Michael Hampton suggested, instead of using KVM directly use virsh, which simplifies handling virtual machines (not only KVM) a lot. As root, first install the needed packages: apt-get install virtinst libvirt-bin You might want to have network-access on your guest machine you will need to have to create a bridge interface on your Host-system (let's ...


0

Xen HVM is the only type of Xen that will support a different OS. KVM will run anything of course. As for which to choose, that's offtopic on SF.net


1

This is not generally done by pinging or ARP trickery. It's done by paperwork. Every request for IPv4 address assignments requires detailed justification, showing that existing addresses are fully utilized and that (in the case of ARIN) the new assignment will be 80% utilized within 30 days. See the ARIN Number Resource Policy Manual for complete details. ...


0

There is no way to tell for certain that each IP maps to a different server. If you are on the same LAN you can use most IP scanning tools (or ping them and look at your ARP table) to match the IP addresses to network cards. But that still doesn't mean unique servers (virtual or physical), since you could add 20 network cards to one VPS. Even worse, they ...


0

You cannot do this. MAC addresses are only useful on Layer 2 networks. And besides, interfaces with multiple IP addresses do not need to have their own MAC.


0

looking in /etc/libvirt/libvirtd.conf: # UNIX socket access controls # # Set the UNIX domain socket group ownership. This can be used to # allow a 'trusted' set of users access to management capabilities # without becoming root. # # This is restricted to 'root' by default. #unix_sock_group = "libvirt" # Set the UNIX socket permissions for the R/O socket. ...


0

The latter. For normal workloads there is nothing you can only do with one or another. If you come from OpenVZ I would suggest KVM since it's architecture is more similar to what you know. Xen is a completely different concept.


0

If the host is the router for the guest, then you must install, configure and run radvd on the host. For this to work, do not filter/discard neighbor discovery packets. Otherwise the guest will not see a default route. You could also configure the default route manually, but that's tedious and error prone. Addendum: don't forget to enable forwarding on the ...


2

...fortunately the process is pretty straightforward. Prerequisites/preparation In order to increase cpu count during runtime you need to configure the VM to have a "maximum" vcpu count and a lower "current" cpu count. An example xml extract (modify using virsh edit ): <vcpu placement='static' current='4'>16</vcpu> Perform the increase ...


1

The easy way to do this is to run virt-manager on your desktop and set it up with a remote ssh connection to the hypervisor, the server running your new virtual machine. The hard way to do this is by running virsh vncdisplay guest_name on the server. This will give you VNC connection information. But, you may find this unusable as it may only be bound to ...


0

After a longer search I found this very simple/easy solution - if you know it: http://adamdoupe.com/blog/2010/10/22/configuring-linux-bridge-to-act-as-a-hub/ brctl setageing <bridgename> 0


0

Check cat /proc/`pidof qemu-kvm`/limits to see if the limits are actually set after restart.


3

I would say you have a lot more to consider than just hard drives. You are intending to transfer to a completely different virtualization package, which will take much more than a days worth of work. Theoretically you would need to: - Transcribe the VM configurations (more than likely by hand) from Microsoft's spec to QEmu's spec. - Convert the VHD images ...



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