
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc. 3X of the following: Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic Boot/OS will likely be two cheaper small sata/ssd in raid 1. Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one? I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs. I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network. In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed. I would love to hear any advice or critiques on this plan. Thanks!

Hi, You should be ok with the setup. I am running around 20 vms (linux and windows, small and medium size) with the half of your specs. With 10G network replica 3 is ok. Alex On Wed, Apr 4, 2018, 16:13 Jayme <jaymef@gmail.com> wrote:
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc.
3X of the following:
Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic
Boot/OS will likely be two cheaper small sata/ssd in raid 1.
Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one?
I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs.
I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network.
In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed.
I would love to hear any advice or critiques on this plan.
Thanks! _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

Thanks for your feedback. Any other opinions on this proposed setup? I'm very torn over using GlusterFS and what the expected performance may be, there seems to be little information out there. Would love to hear any feedback specifically from ovirt users on hyperconverged configurations. On Thu, Apr 5, 2018 at 2:56 AM, Alex K <rightkicktech@gmail.com> wrote:
Hi,
You should be ok with the setup. I am running around 20 vms (linux and windows, small and medium size) with the half of your specs. With 10G network replica 3 is ok.
Alex
On Wed, Apr 4, 2018, 16:13 Jayme <jaymef@gmail.com> wrote:
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc.
3X of the following:
Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic
Boot/OS will likely be two cheaper small sata/ssd in raid 1.
Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one?
I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs.
I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network.
In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed.
I would love to hear any advice or critiques on this plan.
Thanks! _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

Jayme, I'm doing a very similar build, the only difference really is I am using SSDs instead of HDDs. I have similar questions as you regarding expected performance. Have you considered JBOD + NFS? Putting a Gluster Replica 3 on top of RAID 10 arrays sounds very safe, but my gosh the capacity takes a massive hit. Am I correct in saying you will only get 4TB total usable capacity out of 24TB worth of disks? The cost per TB in that sort of scenario is immense. My plan is two 2TB SSDs per server in JBOD with a caching raid card, with replica 3. I would end up with the same 4TB total capacity using 12TB of SSDs. I think Replica 3 is safe enough that you could forgo the RAID 10. But I'm talking from zero experience... Would love others to chime in with their opinions on both these setups. *Vincent Royer* *778-825-1057* <http://www.epicenergy.ca/> *SUSTAINABLE MOBILE ENERGY SOLUTIONS* On Thu, Apr 5, 2018 at 12:22 PM, Jayme <jaymef@gmail.com> wrote:
Thanks for your feedback. Any other opinions on this proposed setup? I'm very torn over using GlusterFS and what the expected performance may be, there seems to be little information out there. Would love to hear any feedback specifically from ovirt users on hyperconverged configurations.
On Thu, Apr 5, 2018 at 2:56 AM, Alex K <rightkicktech@gmail.com> wrote:
Hi,
You should be ok with the setup. I am running around 20 vms (linux and windows, small and medium size) with the half of your specs. With 10G network replica 3 is ok.
Alex
On Wed, Apr 4, 2018, 16:13 Jayme <jaymef@gmail.com> wrote:
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc.
3X of the following:
Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic
Boot/OS will likely be two cheaper small sata/ssd in raid 1.
Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one?
I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs.
I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network.
In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed.
I would love to hear any advice or critiques on this plan.
Thanks! _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

I always found replica 3 a complete overkill. Don't know people made that up that was necessary. Just looks good and costs a lot with little benefit. Normally when using magnetic disks 2 copies are fine for most scenarios, but if using SSDs for similar scenarios depending on the configuration of each node disks it is possible to have a RAID 5/6 ish. Fernando 2018-04-05 17:38 GMT-03:00 Vincent Royer <vincent@epicenergy.ca>:
Jayme,
I'm doing a very similar build, the only difference really is I am using SSDs instead of HDDs. I have similar questions as you regarding expected performance. Have you considered JBOD + NFS? Putting a Gluster Replica 3 on top of RAID 10 arrays sounds very safe, but my gosh the capacity takes a massive hit. Am I correct in saying you will only get 4TB total usable capacity out of 24TB worth of disks? The cost per TB in that sort of scenario is immense.
My plan is two 2TB SSDs per server in JBOD with a caching raid card, with replica 3. I would end up with the same 4TB total capacity using 12TB of SSDs.
I think Replica 3 is safe enough that you could forgo the RAID 10. But I'm talking from zero experience... Would love others to chime in with their opinions on both these setups.
*Vincent Royer* *778-825-1057*
<http://www.epicenergy.ca/> *SUSTAINABLE MOBILE ENERGY SOLUTIONS*
On Thu, Apr 5, 2018 at 12:22 PM, Jayme <jaymef@gmail.com> wrote:
Thanks for your feedback. Any other opinions on this proposed setup? I'm very torn over using GlusterFS and what the expected performance may be, there seems to be little information out there. Would love to hear any feedback specifically from ovirt users on hyperconverged configurations.
On Thu, Apr 5, 2018 at 2:56 AM, Alex K <rightkicktech@gmail.com> wrote:
Hi,
You should be ok with the setup. I am running around 20 vms (linux and windows, small and medium size) with the half of your specs. With 10G network replica 3 is ok.
Alex
On Wed, Apr 4, 2018, 16:13 Jayme <jaymef@gmail.com> wrote:
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc.
3X of the following:
Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic
Boot/OS will likely be two cheaper small sata/ssd in raid 1.
Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one?
I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs.
I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network.
In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed.
I would love to hear any advice or critiques on this plan.
Thanks! _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

On Thu, Apr 5, 2018, 11:51 PM FERNANDO FREDIANI <fernando.frediani@upx.com> wrote:
I always found replica 3 a complete overkill. Don't know people made that up that was necessary. Just looks good and costs a lot with little benefit.
It's not very easy to solve split brain with only 2. You can use 2+arbiter. Y.
Normally when using magnetic disks 2 copies are fine for most scenarios, but if using SSDs for similar scenarios depending on the configuration of each node disks it is possible to have a RAID 5/6 ish. Fernando
2018-04-05 17:38 GMT-03:00 Vincent Royer <vincent@epicenergy.ca>:
Jayme,
I'm doing a very similar build, the only difference really is I am using SSDs instead of HDDs. I have similar questions as you regarding expected performance. Have you considered JBOD + NFS? Putting a Gluster Replica 3 on top of RAID 10 arrays sounds very safe, but my gosh the capacity takes a massive hit. Am I correct in saying you will only get 4TB total usable capacity out of 24TB worth of disks? The cost per TB in that sort of scenario is immense.
My plan is two 2TB SSDs per server in JBOD with a caching raid card, with replica 3. I would end up with the same 4TB total capacity using 12TB of SSDs.
I think Replica 3 is safe enough that you could forgo the RAID 10. But I'm talking from zero experience... Would love others to chime in with their opinions on both these setups.
*Vincent Royer* *778-825-1057*
<http://www.epicenergy.ca/> *SUSTAINABLE MOBILE ENERGY SOLUTIONS*
On Thu, Apr 5, 2018 at 12:22 PM, Jayme <jaymef@gmail.com> wrote:
Thanks for your feedback. Any other opinions on this proposed setup? I'm very torn over using GlusterFS and what the expected performance may be, there seems to be little information out there. Would love to hear any feedback specifically from ovirt users on hyperconverged configurations.
On Thu, Apr 5, 2018 at 2:56 AM, Alex K <rightkicktech@gmail.com> wrote:
Hi,
You should be ok with the setup. I am running around 20 vms (linux and windows, small and medium size) with the half of your specs. With 10G network replica 3 is ok.
Alex
On Wed, Apr 4, 2018, 16:13 Jayme <jaymef@gmail.com> wrote:
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc.
3X of the following:
Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic
Boot/OS will likely be two cheaper small sata/ssd in raid 1.
Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one?
I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs.
I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network.
In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed.
I would love to hear any advice or critiques on this plan.
Thanks! _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

Vincent, I've been back and forth on SSDs vs HDDs and can't really get a clear answer. You are correct though, it would only equal 4TB usable in the end which is pretty crazy but that amount of 7200 RPM HDDs equals about the same cost as 3 2TB ssds would. I actually posted a question to this list not long ago asking how GlusterFS might perform with a small amount of disks such as one 2TB SSD per host and some glusterFS users commented stating that network would be the bottleneck long before the disks and a small amount of SSDs could bottleneck at RPC layer. Also, I believe at this time GlusterFS is not exactly developed to take full advantage of SSDs (but I believe there has been strides being made in that regard, I could be wrong here). As for replica 3 being overkill that may be true as well but from what I've read on Ovirt and GlusterFS list archives people typically feel safer with replica 3 and run in to less disaster scenarios and can provide easier recovery. I'm not sold on Replica 3 either, Rep 3 Arbiter 1 may be more than fine but I wanted to err on the side of caution as this setup may host production servers sometime in the future. I really wish I could get some straight answers on best configuration for Ovirt + GlusterFS but thus far it has been a big question mark. I don't know if Raid is better than JBOD and I don't know if a smaller number of SSDs would perform any better/worse than larger number of spinning disks in raid 10. On Thu, Apr 5, 2018 at 5:38 PM, Vincent Royer <vincent@epicenergy.ca> wrote:
Jayme,
I'm doing a very similar build, the only difference really is I am using SSDs instead of HDDs. I have similar questions as you regarding expected performance. Have you considered JBOD + NFS? Putting a Gluster Replica 3 on top of RAID 10 arrays sounds very safe, but my gosh the capacity takes a massive hit. Am I correct in saying you will only get 4TB total usable capacity out of 24TB worth of disks? The cost per TB in that sort of scenario is immense.
My plan is two 2TB SSDs per server in JBOD with a caching raid card, with replica 3. I would end up with the same 4TB total capacity using 12TB of SSDs.
I think Replica 3 is safe enough that you could forgo the RAID 10. But I'm talking from zero experience... Would love others to chime in with their opinions on both these setups.
*Vincent Royer* *778-825-1057*
<http://www.epicenergy.ca/> *SUSTAINABLE MOBILE ENERGY SOLUTIONS*
On Thu, Apr 5, 2018 at 12:22 PM, Jayme <jaymef@gmail.com> wrote:
Thanks for your feedback. Any other opinions on this proposed setup? I'm very torn over using GlusterFS and what the expected performance may be, there seems to be little information out there. Would love to hear any feedback specifically from ovirt users on hyperconverged configurations.
On Thu, Apr 5, 2018 at 2:56 AM, Alex K <rightkicktech@gmail.com> wrote:
Hi,
You should be ok with the setup. I am running around 20 vms (linux and windows, small and medium size) with the half of your specs. With 10G network replica 3 is ok.
Alex
On Wed, Apr 4, 2018, 16:13 Jayme <jaymef@gmail.com> wrote:
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc.
3X of the following:
Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic
Boot/OS will likely be two cheaper small sata/ssd in raid 1.
Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one?
I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs.
I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network.
In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed.
I would love to hear any advice or critiques on this plan.
Thanks! _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

Well good, we can at least bounce ideas off each other, and I'm sure we'll get some good advice sooner or later! Best way to get good ideas on the internet is to post bad ones and wait ;) In the performance and sizing guide PDF, they make this statement: *Standard servers with 4:2 erasure coding and JBOD bricks provide superior value in terms of throughput * *per server cost.* I don't know enough about erasure coding to know if that applies, but all the graphs that involve JBOD in that document look pretty good to me. What do you know about ZFS? Seems to be popular to use it in combination with Gluster. On Thu, Apr 5, 2018, 2:38 PM Jayme, <jaymef@gmail.com> wrote:
Vincent,
I've been back and forth on SSDs vs HDDs and can't really get a clear answer. You are correct though, it would only equal 4TB usable in the end which is pretty crazy but that amount of 7200 RPM HDDs equals about the same cost as 3 2TB ssds would. I actually posted a question to this list not long ago asking how GlusterFS might perform with a small amount of disks such as one 2TB SSD per host and some glusterFS users commented stating that network would be the bottleneck long before the disks and a small amount of SSDs could bottleneck at RPC layer. Also, I believe at this time GlusterFS is not exactly developed to take full advantage of SSDs (but I believe there has been strides being made in that regard, I could be wrong here).
As for replica 3 being overkill that may be true as well but from what I've read on Ovirt and GlusterFS list archives people typically feel safer with replica 3 and run in to less disaster scenarios and can provide easier recovery. I'm not sold on Replica 3 either, Rep 3 Arbiter 1 may be more than fine but I wanted to err on the side of caution as this setup may host production servers sometime in the future.
I really wish I could get some straight answers on best configuration for Ovirt + GlusterFS but thus far it has been a big question mark. I don't know if Raid is better than JBOD and I don't know if a smaller number of SSDs would perform any better/worse than larger number of spinning disks in raid 10.
On Thu, Apr 5, 2018 at 5:38 PM, Vincent Royer <vincent@epicenergy.ca> wrote:
Jayme,
I'm doing a very similar build, the only difference really is I am using SSDs instead of HDDs. I have similar questions as you regarding expected performance. Have you considered JBOD + NFS? Putting a Gluster Replica 3 on top of RAID 10 arrays sounds very safe, but my gosh the capacity takes a massive hit. Am I correct in saying you will only get 4TB total usable capacity out of 24TB worth of disks? The cost per TB in that sort of scenario is immense.
My plan is two 2TB SSDs per server in JBOD with a caching raid card, with replica 3. I would end up with the same 4TB total capacity using 12TB of SSDs.
I think Replica 3 is safe enough that you could forgo the RAID 10. But I'm talking from zero experience... Would love others to chime in with their opinions on both these setups.
*Vincent Royer* *778-825-1057*
<http://www.epicenergy.ca/> *SUSTAINABLE MOBILE ENERGY SOLUTIONS*
On Thu, Apr 5, 2018 at 12:22 PM, Jayme <jaymef@gmail.com> wrote:
Thanks for your feedback. Any other opinions on this proposed setup? I'm very torn over using GlusterFS and what the expected performance may be, there seems to be little information out there. Would love to hear any feedback specifically from ovirt users on hyperconverged configurations.
On Thu, Apr 5, 2018 at 2:56 AM, Alex K <rightkicktech@gmail.com> wrote:
Hi,
You should be ok with the setup. I am running around 20 vms (linux and windows, small and medium size) with the half of your specs. With 10G network replica 3 is ok.
Alex
On Wed, Apr 4, 2018, 16:13 Jayme <jaymef@gmail.com> wrote:
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc.
3X of the following:
Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic
Boot/OS will likely be two cheaper small sata/ssd in raid 1.
Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one?
I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs.
I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network.
In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed.
I would love to hear any advice or critiques on this plan.
Thanks! _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

On Fri, Apr 6, 2018, 12:39 AM Jayme <jaymef@gmail.com> wrote:
Vincent,
I've been back and forth on SSDs vs HDDs and can't really get a clear answer. You are correct though, it would only equal 4TB usable in the end which is pretty crazy but that amount of 7200 RPM HDDs equals about the same cost as 3 2TB ssds would. I actually posted a question to this list not long ago asking how GlusterFS might perform with a small amount of disks such as one 2TB SSD per host and some glusterFS users commented stating that network would be the bottleneck long before the disks and a small amount of SSDs could bottleneck at RPC layer. Also, I believe at this time GlusterFS is not exactly developed to take full advantage of SSDs (but I believe there has been strides being made in that regard, I could be wrong here).
Coming real soon now are some very cool features that will make decisions somewhat harder: dedup+compression (from VDO) and lvmcache setup.
As for replica 3 being overkill that may be true as well but from what I've read on Ovirt and GlusterFS list archives people typically feel safer with replica 3 and run in to less disaster scenarios and can provide easier recovery. I'm not sold on Replica 3 either, Rep 3 Arbiter 1 may be more than fine but I wanted to err on the side of caution as this setup may host production servers sometime in the future.
I really wish I could get some straight answers on best configuration for Ovirt + GlusterFS but thus far it has been a big question mark. I don't know if Raid is better than JBOD and I don't know if a smaller number of SSDs would perform any better/worse than larger number of spinning disks in raid 10.
RAID is better than JBOD in terms of availability and most likely performance. It's also more expensive and requires initial setup. SSD will perform better than HDD. It's also more expensive than HDD. No one but you can provide what works best for your requirements. Y.
On Thu, Apr 5, 2018 at 5:38 PM, Vincent Royer <vincent@epicenergy.ca> wrote:
Jayme,
I'm doing a very similar build, the only difference really is I am using SSDs instead of HDDs. I have similar questions as you regarding expected performance. Have you considered JBOD + NFS? Putting a Gluster Replica 3 on top of RAID 10 arrays sounds very safe, but my gosh the capacity takes a massive hit. Am I correct in saying you will only get 4TB total usable capacity out of 24TB worth of disks? The cost per TB in that sort of scenario is immense.
My plan is two 2TB SSDs per server in JBOD with a caching raid card, with replica 3. I would end up with the same 4TB total capacity using 12TB of SSDs.
I think Replica 3 is safe enough that you could forgo the RAID 10. But I'm talking from zero experience... Would love others to chime in with their opinions on both these setups.
*Vincent Royer* *778-825-1057*
<http://www.epicenergy.ca/> *SUSTAINABLE MOBILE ENERGY SOLUTIONS*
On Thu, Apr 5, 2018 at 12:22 PM, Jayme <jaymef@gmail.com> wrote:
Thanks for your feedback. Any other opinions on this proposed setup? I'm very torn over using GlusterFS and what the expected performance may be, there seems to be little information out there. Would love to hear any feedback specifically from ovirt users on hyperconverged configurations.
On Thu, Apr 5, 2018 at 2:56 AM, Alex K <rightkicktech@gmail.com> wrote:
Hi,
You should be ok with the setup. I am running around 20 vms (linux and windows, small and medium size) with the half of your specs. With 10G network replica 3 is ok.
Alex
On Wed, Apr 4, 2018, 16:13 Jayme <jaymef@gmail.com> wrote:
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc.
3X of the following:
Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic
Boot/OS will likely be two cheaper small sata/ssd in raid 1.
Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one?
I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs.
I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network.
In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed.
I would love to hear any advice or critiques on this plan.
Thanks! _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

On Thu, Apr 5, 2018, 11:39 PM Vincent Royer <vincent@epicenergy.ca> wrote:
Jayme,
I'm doing a very similar build, the only difference really is I am using SSDs instead of HDDs. I have similar questions as you regarding expected performance. Have you considered JBOD + NFS? Putting a Gluster Replica 3 on top of RAID 10 arrays sounds very safe, but my gosh the capacity takes a massive hit. Am I correct in saying you will only get 4TB total usable capacity out of 24TB worth of disks? The cost per TB in that sort of scenario is immense.
My plan is two 2TB SSDs per server in JBOD with a caching raid card, with replica 3. I would end up with the same 4TB total capacity using 12TB of SSDs.
I'm not sure I see the value in RAID card if you don't use RAID and I'm not sure you really need caching on the card. Y.
I think Replica 3 is safe enough that you could forgo the RAID 10. But I'm talking from zero experience... Would love others to chime in with their opinions on both these setups.
*Vincent Royer* *778-825-1057*
<http://www.epicenergy.ca/> *SUSTAINABLE MOBILE ENERGY SOLUTIONS*
On Thu, Apr 5, 2018 at 12:22 PM, Jayme <jaymef@gmail.com> wrote:
Thanks for your feedback. Any other opinions on this proposed setup? I'm very torn over using GlusterFS and what the expected performance may be, there seems to be little information out there. Would love to hear any feedback specifically from ovirt users on hyperconverged configurations.
On Thu, Apr 5, 2018 at 2:56 AM, Alex K <rightkicktech@gmail.com> wrote:
Hi,
You should be ok with the setup. I am running around 20 vms (linux and windows, small and medium size) with the half of your specs. With 10G network replica 3 is ok.
Alex
On Wed, Apr 4, 2018, 16:13 Jayme <jaymef@gmail.com> wrote:
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc.
3X of the following:
Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic
Boot/OS will likely be two cheaper small sata/ssd in raid 1.
Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one?
I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs.
I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network.
In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed.
I would love to hear any advice or critiques on this plan.
Thanks! _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

Yaniv, I appreciate your input, thanks! I understand that everyone's use case is different, but I was hoping to hear from some users that are using oVirt hyper-converged setup and get some input on the performance. When I research GlusterFS I hear a lot about how it can be slow especially when dealing with small files. I'm starting to wonder if a straight up NFS server with a few SSDs would be less hassle and perhaps offer better VM performance than glusterFS can currently. I want to get the best oVirt performance I can get (on somewhat of a budget) with a fairly small amount of required disk space (under 2TB). I'm not sure if hyper-converged setup w/GlusterFS is the answer or not. I'd like to avoid spending 15k only to find out that it's too slow. On Fri, Apr 6, 2018 at 6:05 AM, Yaniv Kaul <ykaul@redhat.com> wrote:
On Thu, Apr 5, 2018, 11:39 PM Vincent Royer <vincent@epicenergy.ca> wrote:
Jayme,
I'm doing a very similar build, the only difference really is I am using SSDs instead of HDDs. I have similar questions as you regarding expected performance. Have you considered JBOD + NFS? Putting a Gluster Replica 3 on top of RAID 10 arrays sounds very safe, but my gosh the capacity takes a massive hit. Am I correct in saying you will only get 4TB total usable capacity out of 24TB worth of disks? The cost per TB in that sort of scenario is immense.
My plan is two 2TB SSDs per server in JBOD with a caching raid card, with replica 3. I would end up with the same 4TB total capacity using 12TB of SSDs.
I'm not sure I see the value in RAID card if you don't use RAID and I'm not sure you really need caching on the card. Y.
I think Replica 3 is safe enough that you could forgo the RAID 10. But I'm talking from zero experience... Would love others to chime in with their opinions on both these setups.
*Vincent Royer* *778-825-1057*
<http://www.epicenergy.ca/> *SUSTAINABLE MOBILE ENERGY SOLUTIONS*
On Thu, Apr 5, 2018 at 12:22 PM, Jayme <jaymef@gmail.com> wrote:
Thanks for your feedback. Any other opinions on this proposed setup? I'm very torn over using GlusterFS and what the expected performance may be, there seems to be little information out there. Would love to hear any feedback specifically from ovirt users on hyperconverged configurations.
On Thu, Apr 5, 2018 at 2:56 AM, Alex K <rightkicktech@gmail.com> wrote:
Hi,
You should be ok with the setup. I am running around 20 vms (linux and windows, small and medium size) with the half of your specs. With 10G network replica 3 is ok.
Alex
On Wed, Apr 4, 2018, 16:13 Jayme <jaymef@gmail.com> wrote:
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc.
3X of the following:
Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic
Boot/OS will likely be two cheaper small sata/ssd in raid 1.
Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one?
I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs.
I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network.
In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed.
I would love to hear any advice or critiques on this plan.
Thanks! _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

It's likely possibile you will get more performance from a NFS server compared to Gluster. Specially if on your NFS server you have something like ZFS + SSD for L2ARC or ext4 + Bcache, but you get not redundancy. If you NFS server dies everything stops working, which is not the case with Distributed Storage. Fernando 2018-04-06 10:45 GMT-03:00 Jayme <jaymef@gmail.com>:
Yaniv,
I appreciate your input, thanks!
I understand that everyone's use case is different, but I was hoping to hear from some users that are using oVirt hyper-converged setup and get some input on the performance. When I research GlusterFS I hear a lot about how it can be slow especially when dealing with small files. I'm starting to wonder if a straight up NFS server with a few SSDs would be less hassle and perhaps offer better VM performance than glusterFS can currently.
I want to get the best oVirt performance I can get (on somewhat of a budget) with a fairly small amount of required disk space (under 2TB). I'm not sure if hyper-converged setup w/GlusterFS is the answer or not. I'd like to avoid spending 15k only to find out that it's too slow.
On Fri, Apr 6, 2018 at 6:05 AM, Yaniv Kaul <ykaul@redhat.com> wrote:
On Thu, Apr 5, 2018, 11:39 PM Vincent Royer <vincent@epicenergy.ca> wrote:
Jayme,
I'm doing a very similar build, the only difference really is I am using SSDs instead of HDDs. I have similar questions as you regarding expected performance. Have you considered JBOD + NFS? Putting a Gluster Replica 3 on top of RAID 10 arrays sounds very safe, but my gosh the capacity takes a massive hit. Am I correct in saying you will only get 4TB total usable capacity out of 24TB worth of disks? The cost per TB in that sort of scenario is immense.
My plan is two 2TB SSDs per server in JBOD with a caching raid card, with replica 3. I would end up with the same 4TB total capacity using 12TB of SSDs.
I'm not sure I see the value in RAID card if you don't use RAID and I'm not sure you really need caching on the card. Y.
I think Replica 3 is safe enough that you could forgo the RAID 10. But I'm talking from zero experience... Would love others to chime in with their opinions on both these setups.
*Vincent Royer* *778-825-1057*
<http://www.epicenergy.ca/> *SUSTAINABLE MOBILE ENERGY SOLUTIONS*
On Thu, Apr 5, 2018 at 12:22 PM, Jayme <jaymef@gmail.com> wrote:
Thanks for your feedback. Any other opinions on this proposed setup? I'm very torn over using GlusterFS and what the expected performance may be, there seems to be little information out there. Would love to hear any feedback specifically from ovirt users on hyperconverged configurations.
On Thu, Apr 5, 2018 at 2:56 AM, Alex K <rightkicktech@gmail.com> wrote:
Hi,
You should be ok with the setup. I am running around 20 vms (linux and windows, small and medium size) with the half of your specs. With 10G network replica 3 is ok.
Alex
On Wed, Apr 4, 2018, 16:13 Jayme <jaymef@gmail.com> wrote:
I'm spec'ing hardware for a 3-node oVirt build (on somewhat of a budget). I plan to do 20-30 Linux VMs most of them very light weight + a couple of heavier hitting web and DB servers with frequent rsync backups. Some have a lot of small files from large github repos etc.
3X of the following:
Dell PowerEdge R720 2x 2.9 GHz 8 Core E5-2690 (SR0L0) 256GB RAM PERC H710 2x10GB Nic
Boot/OS will likely be two cheaper small sata/ssd in raid 1.
Gluster bricks comprised of 4x2TB WD Gold 7200RPM SATA HDDs in RAID 10 per server. Using a replica 3 setup (and I'm thinking right now with no arbiter for extra redundancy, although I'm not sure what the performance hit may be as a result). Will this allow for two host failure or just one?
I've been really struggling with storage choices, it seems very difficult to predict the performance of glusterFS due to the variance in hardware (everyone is using something different). I'm not sure if the performance will be adequate enough for my needs.
I will be using an all ready existing Netgear XS716T 10GB switch for Gluster storage network.
In addition I plan to build another simple glusterFS storage server that I can use to georeplicate the gluster volume to for DR purposes and use existing hardware to build an independent standby oVirt host that is able to start up a few high priority VMs from the georeplicated glusterFS volume if for some reason the primary oVirt cluster/glusterFS volume ever failed.
I would love to hear any advice or critiques on this plan.
Thanks! _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users

Also keep in mind that extensive logging in the vm's can seriously impact your fs performance, so using a central syslogserver is a really good idea. /tony On 2018-04-06 17:03, Karli Sjöberg wrote:
Den 6 apr. 2018 15:46 skrev Jayme <jaymef@gmail.com>:
Yaniv,
I appreciate your input, thanks!
I understand that everyone's use case is different, but I was hoping to hear from some users that are using oVirt hyper-converged setup and get some input on the performance. When I research GlusterFS I hear a lot about how it can be slow especially when dealing with small files. I'm starting to wonder if a straight up NFS server with a few SSDs would be less hassle and perhaps offer better VM performance than glusterFS can currently.
I want to get the best oVirt performance I can get (on somewhat of a budget) with a fairly small amount of required disk space (under 2TB). I'm not sure if hyper-converged setup w/GlusterFS is the answer or not. I'd like to avoid spending 15k only to find out that it's too slow.
What is "too slow" for you, what are your expectations?
Much depending on that, you will find that different goals require different tools. Like hammering on a screw and all that :)
/K
-- Tony Albers Systems administrator, IT-development Royal Danish Library, Victor Albecks Vej 1, 8000 Aarhus C, Denmark. Tel: +45 2566 2383 / +45 8946 2316
participants (7)
-
Alex K
-
FERNANDO FREDIANI
-
Jayme
-
Karli Sjöberg
-
Tony Brian Albers
-
Vincent Royer
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Yaniv Kaul