[ovirt-users] Re: oVirt install questions

Thanks. I've only been considering SSD drives for storage, as that is what I currently have in the cloud. I think I've seen some things in the documents about oVirt and gluster hyperconverged. Is it possible to run oVirt and Gluster together on the same hardware? So 3 physical hosts would run CentOS or something, and I would install oVirt Node + Gluster onto the same base host OS? If so, then I could probably make that fit into my budget. Sent with ProtonMail Secure Email. ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ On Monday, June 22, 2020 1:02 PM, Strahil Nikolov via Users < users(a)ovirt.org&gt; wrote: > Hey David, > > keep in mind that you need some big NICs. > I started my oVirt lab with 1 Gbit NIC and later added 4 dual-port 1 Gbit NICs and I had to create multiple gluster volumes and multiple storage domains. > Yet, windows VMs cannot use software raid for boot devices, thus it's a pain in the @$$. > I think that optimal is to have several 10Gbit NICs (at least 1 for gluster and 1 for oVirt live migration). > Also, NVMEs can be used as lvm cache for spinning disks. > > Best Regards, > Strahil Nikolov > > На 22 юни 2020 г. 18:50:01 GMT+03:00, David White dmwhite823(a)protonmail.com написа: > > > > For migration between hosts you need a shared storage. SAN, Gluster, > > > CEPH, NFS, iSCSI are among the ones already supported (CEPH is a little > > > bit experimental). > > > > Sounds like I'll be using NFS or Gluster after all. > > Thank you. > > > > > The engine is just a management layer. KVM/qemu has that option a > > > long time ago, yet it's some manual work to do it. > > > Yeah, this environment that I'm building is expected to grow over time > > > (although that growth could go slowly), so I'm trying to architect > > > things properly now to make future growth easier to deal with. I'm also > > > trying to balance availability concerns with budget constraints > > > starting out. > > > > Given that NFS would also be a single point of failure, I'll probably > > go with Gluster, as long as I can fit the storage requirements into the > > overall budget. > > Sent with ProtonMail Secure Email. > > ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ > > On Monday, June 22, 2020 6:31 AM, Strahil Nikolov via Users > > users(a)ovirt.org wrote: > > > > > На 22 юни 2020 г. 11:06:16 GMT+03:00, David White via > > > Usersusers(a)ovirt.org написа: > > > > > > Thank you and Strahil for your responses. > > > > They were both very helpful. > > > > > > > I think a hosted engine installation VM wants 16GB RAM configured > > > > > though I've built older versions with 8GB RAM. > > > > > For modern VMs CentOS8 x86_64 recommends at least 2GB for a host. > > > > > CentOS7 was OK with 1, CentOS6 maybe 512K. > > > > > The tendency is always increasing with updated OS versions. > > > > > > Ok, so to clarify my question a little bit, I'm trying to figure > > > > out > > > > > > > how much RAM I would need to reserve for the host OS (or oVirt > > > > Node). > > > > > > > I do recall that CentOS / RHEL 8 wants a minimum of 2GB, so perhaps > > > > that would suffice? > > > > And then as you noted, I would need to plan to give the engine > > > > 16GB. > > > > > I run my engine on 4Gb or RAM, but i have no more than 20 VMs, the > > > larger the setup - the more ram for the engine is needed. > > > > > > > My minimum ovirt systems were mostly 48GB 16core, but most are > > > > > now > > > > > > > > 128GB 24core or more. > > > > > > But this is the total amount of physical RAM in your systems, > > > > correct? > > > > > > > Not the amount that you've reserved for your host OS?I've spec'd > > > > out > > > > > > > some hardware, and am probably looking at purchasing two PowerEdge > > > > R820's to start, each with 64GB RAM and 32 cores. > > > > > > > While ovirt can do what you would like it to do concerning a > > > > > single > > > > > > > > user interface, but with what you listed, > > > > > you're probably better off with just plain KVM/qemu and using > > > > > virt-manager for the interface. > > > > > > Can you migrate VMs from 1 host to another with virt-manager, and > > > > can > > > > > > > you take snapshots? > > > > If those two features aren't supported by virt-manager, then that > > > > would > > > > > > > almost certainly be a deal breaker. > > > > > The engine is just a management layer. KVM/qemu has that option a > > > long time ago, yet it's some manual work to do it. > > > > > > Come to think of it, if I decided to use local storage on each of > > > > the > > > > > > > physical hosts, would I be able to migrate VMs? > > > > Or do I have to use a Gluster or NFS store for that? > > > > > For migration between hosts you need a shared storage. SAN, Gluster, > > > CEPH, NFS, iSCSI are among the ones already supported (CEPH is a little > > > bit experimental). > > > > > > ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ > > > > On Sunday, June 21, 2020 5:58 PM, Edward Berger edwberger(a)gmail.com > > > > wrote: > > > > > > > While ovirt can do what you would like it to do concerning a > > > > > single > > > > > > > > user interface, but with what you listed, > > > > > you're probably better off with just plain KVM/qemu and using > > > > > virt-manager for the interface. > > > > > > > Those memory/cpu requirements you listed are really tiny and I > > > > > wouldn't recommend even trying ovirt on such challenged systems. > > > > > I would specify at least 3 hosts for a gluster hyperconverged > > > > > system, > > > > > > > > and a spare available that can take over if one of the hosts > > > > > dies. > > > > > > > > > > > > > > I think a hosted engine installation VM wants 16GB RAM configured > > > > > though I've built older versions with 8GB RAM. > > > > > For modern VMs CentOS8 x86_64 recommends at least 2GB for a host. > > > > > CentOS7 was OK with 1, CentOS6 maybe 512K. > > > > > The tendency is always increasing with updated OS versions. > > > > > > > My minimum ovirt systems were mostly 48GB 16core, but most are > > > > > now > > > > > > > > 128GB 24core or more. > > > > > > > ovirt node ng is a prepackaged installer for an oVirt > > > > > hypervisor/gluster host, with its cockpit interface you can > > > > > create and > > > > > > > > install the hosted-engine VM for the user and admin web > > > > > interface. Its > > > > > > > > very good on enterprise server hardware with lots of RAM,CPU, and > > > > > DISKS. > > > > > > > On Sun, Jun 21, 2020 at 4:34 PM David White via Users > > > > > users(a)ovirt.org wrote: > > > > > > > > I'm reading through all of the documentation at > > > > > > https://ovirt.org/documentation/, and am a bit overwhelmed with > > > > > > all of > > > > > > > > > the different options for installing oVirt. > > > > > > > > > > > > > > > > > > > > > > My particular use case is that I'm looking for a way to manage > > > > > > VMs > > > > > > > > > on multiple physical servers from 1 interface, and be able to > > > > > > deploy > > > > > > > > > new VMs (or delete VMs) as necessary. Ideally, it would be > > > > > > great if I > > > > > > > > > could move a VM from 1 host to a different host as well, > > > > > > particularly > > > > > > > > > in the event that 1 host becomes degraded (bad HDD, bad > > > > > > processor, > > > > > > > > > etc...) > > > > > > > > > > > > > > > > > > > > > > I'm trying to figure out what the difference is between an > > > > > > oVirt > > > > > > > > > Node and the oVirt Engine, and how the engine differs from the > > > > > > Manager. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > I get the feeling that `Engine` = `Manager`. Same thing. I > > > > > > further > > > > > > > > > think I understand the Engine to be essentially synonymous with > > > > > > a > > > > > > > > > vCenter VM for ESXi hosts. Is this correct? > > > > > > > > > > > > > > > > > > > > > > If so, then what's the difference between the `self-hosted` vs > > > > > > the > > > > > > > > > `stand-alone` engines? > > > > > > > > > > > > > > > > > > > > > > oVirt Engine requirements look to be a minimum of 4GB RAM and > > > > > > 2CPUs. > > > > > > > > oVirt Nodes, on the other hand, require only 2GB RAM. > > > > > > Is this a requirement just for the physical host, or is that > > > > > > how > > > > > > > > > much RAM that each oVirt node process requires? In other words, > > > > > > if I > > > > > > > > > have a physical host with 12GB of physical RAM, will I only be > > > > > > able to > > > > > > > > > allocate 10GB of that to guest VMs? How much of that should I > > > > > > dedicated > > > > > > > > > to the oVirt node processes? > > > > > > > > > > > > > > > > > > > > > > Can you install the oVirt Engine as a VM onto an existing oVirt > > > > > > Node? And then connect that same node to the Engine, once the > > > > > > Engine is > > > > > > > > > installed? > > > > > > > > > > > > > > > > > > > > > > Reading through the documentation, it also sounds like oVirt > > > > > > Engine > > > > > > > > > and oVirt Node require different versions of RHEL or CentOS. > > > > > > > > I read that the Engine for oVirt 4.4.0 requires RHEL (or > > > > > > CentOS) > > > > > > > > > 8.2, whereas each Node requires 7.x (although I'll plan to just > > > > > > use the > > > > > > > > > oVirt Node ISO). > > > > > > > > > > > > > > > > > > > > > > I'm also wondering about storage. > > > > > > I don't really like the idea of using local storage, but a > > > > > > single > > > > > > > > > NFS server would also be a single point of failure, and Gluster > > > > > > would > > > > > > > > > be too expensive to deploy, so at this point, I'm leaning > > > > > > towards using > > > > > > > > > local storage. > > > > > > > > > > > > > > > > > > > > > > Any advice or clarity would be greatly appreciated. > > > > > > > > Thanks, > > > > > > David > > > > > > > > Sent with ProtonMail Secure Email. > > > > > > > > Users mailing list -- users(a)ovirt.org > > > > > > To unsubscribe send an email to users-leave(a)ovirt.org > > > > > > Privacy Statement: https://www.ovirt.org/privacy-policy.html > > > > > > oVirt Code of Conduct: > > > > > > https://www.ovirt.org/community/about/community-guidelines/ > > > > > > > > List Archives: > > > > https://lists.ovirt.org/archives/list/users@ovirt.org/message/RGHCN356DXJ... > > > > > > > > > > Users mailing list -- users(a)ovirt.org > > > To unsubscribe send an email to users-leave(a)ovirt.org > > > Privacy Statement: https://www.ovirt.org/privacy-policy.html > > > oVirt Code of Conduct: > > > https://www.ovirt.org/community/about/community-guidelines/ > > > List Archives: > > > https://lists.ovirt.org/archives/list/users@ovirt.org/message/TF63JRHWDBC... > > Users mailing list -- users(a)ovirt.org > To unsubscribe send an email to users-leave(a)ovirt.org > Privacy Statement: https://www.ovirt.org/privacy-policy.html > oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ > List Archives: https://lists.ovirt.org/archives/list/users@ovirt.org/message/GKCVKWJJ56I... _______________________________________________ Users mailing list -- users(a)ovirt.org To unsubscribe send an email to users-leave(a)ovirt.org Privacy Statement: https://www.ovirt.org/privacy-policy.html oVirt Code of Conduct: https://www.ovirt.org/community/about/community-guidelines/ List Archives: https://lists.ovirt.org/archives/list/users@ovirt.org/message/JYFSHSV4IZB...