booting KVM VM from an iso image

let’s say you have a vm, maybe with debian. and that vm stopped booting, maybe because of grub corruption. what do you do? add under devices – for pc-i440fx arch: and for pc-q35-3.1: then in the os section change boot from dev=’hd’ to dev=’cdrom’: then also – this article describes how to go back from …

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20x performance difference between two VMs running the same version of Elastic opendistro

i’ve just spent way too much time trying to figure out why the same query run on one VM with elastic 0.1s while on another – 2s. both VMs were running on the same physical server, had the same amount of cores allocated. i’ve finally found it – there was a tiny difference in amount …

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“error: internal error: unable to execute QEMU command ‘transaction’: Could not create file: Permission denied” when creating a snapshot under KVM

debian buster brings apparmor. apparmor brings problems – eg it’s too restrictive for libvirt KVM guests and does not allow KVM to create snapshot-related files in VM’s folders. so far i did not find a clean and generic way to address it so i had to disable apparmor for libvirt by adding security_driver = “none” …

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