BTW, if we make this a requirement (decide so, internally) we should have this heavily emphasised in the next release Release Notes (and this also, perhaps, warrants sending some special ANNOUNCE or similar email to user and dev mailing lists - to avoid having seriously pissed off users.
On Thu, 24 Feb 2022, 23:06 Andrija Panic, <andrija.pa...@gmail.com> wrote: > Hi all, > > +1 in general, > > but keep in mind that the "regular" qemu-kmv-ev from the CentOS SIG repo > does NOT support live storage migration (up to version 2.12 at least), and > qemu-kmv-ev from the oVirt repo (essentially a RHEV) need(ed) to be used > for live storage migration (virsh - - migrate-all...) to work. I'm not sure > if this has changed. but perhaps Simon or someone using qemu-kmv-ev may > advice. > > Cheers, > > On Thu, 24 Feb 2022, 15:58 Rohit Yadav, <rohit.ya...@shapeblue.com> wrote: > >> +1 I've seen a lot of users and some of our customers use qemu-kvm-ev in >> production. However, we need to check if qemu-kvm-ev has 100% feature >> parity (I remember my colleague Andrija suggesting something which was >> missing in either stock qemu-kvm or qemu-kvm-ev). >> >> >> Regards. >> >> ________________________________ >> From: Slavka Peleva <slav...@storpool.com.INVALID> >> Sent: Wednesday, February 23, 2022 23:58 >> To: dev <dev@cloudstack.apache.org> >> Subject: Re: [Discussion] CentOS 7 KVM binaries >> >> Hi Daniel, >> >> +1 for qemu-kvm-ev. We also advise our customers to use it. >> >> Best regards, >> Slavka >> >> On Fri, Feb 18, 2022 at 8:51 PM Simon Weller <swel...@ena.com.invalid> >> wrote: >> >> > Daniel, >> > >> > We've used qemu-kvm-ev in production for years. A number of the >> > enhancements we've pushed into Cloudstack have required it. I think >> you'll >> > find that most cloud providers based on Centos (or Alma/Rocky) are also >> > using it. >> > >> > -Si >> > ________________________________ >> > From: Daniel Salvador <gutoveron...@apache.org> >> > Sent: Friday, February 18, 2022 9:53 AM >> > To: dev@cloudstack.apache.org <dev@cloudstack.apache.org> >> > Subject: [Discussion] CentOS 7 KVM binaries >> > >> > Hi all, hope you are doing fine. >> > >> > The following discussion emerged from PR #5297[¹]. >> > >> > It is a known fact that, regarding KVM functionalities, CentOS7 >> default's >> > QEMU binary is quite limited. This is due to the removal of some >> features >> > of KVM default binary in CentOS (like VM's volume live migration, >> > memory/CPU hotplug/hot-unplug, live disk snapshot, and so on); more >> > information can be found in CentOS forum's thread[²]. >> > >> > In my point of view, such limitations in the default QEMU binary in >> CentOS >> > make it unfeasible to build a cloud with CentOS and the default QEMU >> > binary, as operators lose a lot of useful/important operations or have >> to >> > go through workarounds, which cause VM's disruption (e.g. having to >> stop a >> > VM to migrate the volume between different storage pools, which >> triggers a >> > secondary storage usage). There is an alternative binary, "qemu-kvm-ev", >> > which supports more features than the default one. Probably, most people >> > using KVM with CentOS are using the "ev" binary (I might be wrong >> though, >> > however, that seems to be the case when looking at the users' list). >> > >> > PR #5297[¹] ran into one of the CentOS7 default's QEMU binary >> limitations >> > (live disk snapshot). The easiest solution (and, IHMO, is the best >> option) >> > is to guide users to upgrade CentOS7 QEMU binary to "qemu-kvm-ev". >> > >> > Further, it is important to mention that in our experience, it is not >> > possible to run a highly available cloud environment with CentOS7 and >> the >> > default binaries. In a cloud environment with thousands of VMs, sooner >> or >> > later the need to hotplug (increase) CPU/RAM, migrate volumes across >> > different storage pool tyles (such as iSCSI <> NFS), or some other type >> of >> > operation appear, and operators/final customers do not want service >> > disruption. Our customers, for instance, never shut down VMs for these >> > kinds of operations, and that is only possible because they are all >> using >> > KVM with Ubuntu now. >> > >> > Moreover, CentOS7 is getting close to its EOL. Therefore, We do not >> think >> > that CloudStack should limit its features due to a dying operating >> system >> > that presents very limited features by default. >> > >> > With that said, it would be interesting if dev/users that use CentOS7 >> could >> > share their experiences with the "qemu-kvm-ev" in this thread, so we can >> > decide which way to go. Or, users that only use the default binary, if >> they >> > are satisfied with it. >> > >> > If almost no one is relying on default CentOS7 binaries, we could >> define as >> > a step in the documentation, that when using CentOS7 people must use the >> > "ev" binary. This would free us to evolve ACS more freely and avoid >> > headaches with workarounds to a limited operating system when there are >> > alternatives out there. >> > >> > >> > [¹] https://github.com/apache/cloudstack/pull/5297 >> > [²] https://forums.centos.org/viewtopic.php?t=65618 >> > >> >> >> >>
