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 <dmwhite...@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@ovirt.org> wrote: > >> На 22 юни 2020 г. 11:06:16 GMT+03:00, David White via >usersus...@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 edwber...@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@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@ovirt.org >> > > > To unsubscribe send an email to users-le...@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/RGHCN356DXJEDR5FJ7SXSBHBF5FYRWIN/ >> > >> Users mailing list -- users@ovirt.org >> To unsubscribe send an email to users-le...@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/TF63JRHWDBCJWDRW66I3NF6WUKKFHNCX/ _______________________________________________ Users mailing list -- users@ovirt.org To unsubscribe send an email to users-le...@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/GKCVKWJJ56ITACRPSMZGCE2Z47JWUZQI/
