Re: Upgrading the host

On 2/17/2021 12:23 AM, Michal Privoznik wrote: > On 2/17/21 2:45 AM, Marcin Struzak wrote: >> On 2/16/2021 12:51 AM, Michal Privoznik wrote: >>> On 2/12/21 2:10 AM, Marcin Struzak wrote: >>> [...] >>> >>>>  3. Anything else I should worry about or prepare ahead? >>> >>> Not strictly related to libvirt, but machine types might be problem. >>> I guess qemu will be upgraded too and in general the machine type >>> you're using for a domain might not be available in upgraded qemu. >> Correct, it looks like qemu will go from 1.6.2 to 4.2.1... >>> >>> You can view supported machine types by running 'virsh capabilities' >>> with upgraded qemu. >> machine is pc-i440fx-1.6 in all my domains.  Is there a simple way to >> figure out if that's supported in libvirt 6.1.0 (without installing it)? > > It's not libvirt who has say in machine types. Libvirt treats machine > type as an opaque string. But I can see that pc-i440fx-1.6 is still > available even with the latest QEMU release: > > # /usr/bin/qemu-system-x86_64 -version > QEMU emulator version 5.2.0 > > # virsh capabilities | grep pc-i440fx-1.6 >       <machine maxCpus='255'>pc-i440fx-1.6</machine> >       <machine maxCpus='255'>pc-i440fx-1.6</machine> > > So you are safe on that front. Excellent, thank you for checking. Out of curiosity: what would have been my course of action if that particular machine were no longer defined?  I assume: substitute with a close match (after figuring out how do determine what counts as "close") & hope that the VMs (all Fedoras & Ubuntus) cope & adjust?