Posix FS as alternative to local storage?
Hi, I would like to set up a new oVirt deployment with hosts that have the VMs running on local attached storage. I understand this has the requirement of having each host in its own cluster (and own datacenter, it seems, I understand the need for the dedicated cluster, not so much for the dedicated datacenter). At the same time, I would like to have some shared storage domains so I can use it to export VMs or migrate them around hosts (probably in three stages, first migrate VM storage from local to the shared storage domain, second migrate the host (probably not possible to do a "hot" migration, but at least "cold"), third migrate the VM storage from the shared storage domain to the local storage domain of the new host). So I thought maybe I can deploy a datacenter in shared storage mode, with one cluster per host. Use one or two shared storage domains for master and as an stage area for planned VM migrations as explained before, and then configure several storage domains, one per host, as posix FS . I would then deploy the VMs on the local posix FS storage domains and set affinity rules for the VMs to their hosts as needed. Would this work? Is there a better way of achieving local storage and retaining the ability to share storage among hosts and migrate VMs? -- Eduardo Mayoral Jimeno (emayoral@arsys.es) Administrador de sistemas. Departamento de Plataformas. Arsys internet. +34 941 620 145 ext. 5153
On 30/04/18 11:43, Eduardo Mayoral wrote:
Hi,
I would like to set up a new oVirt deployment with hosts that have the VMs running on local attached storage. I understand this has the requirement of having each host in its own cluster (and own datacenter, it seems, I understand the need for the dedicated cluster, not so much for the dedicated datacenter).
At the same time, I would like to have some shared storage domains so I can use it to export VMs or migrate them around hosts (probably in three stages, first migrate VM storage from local to the shared storage domain, second migrate the host (probably not possible to do a "hot" migration, but at least "cold"), third migrate the VM storage from the shared storage domain to the local storage domain of the new host).
So I thought maybe I can deploy a datacenter in shared storage mode, with one cluster per host. Use one or two shared storage domains for master and as an stage area for planned VM migrations as explained before, and then configure several storage domains, one per host, as posix FS . I would then deploy the VMs on the local posix FS storage domains and set affinity rules for the VMs to their hosts as needed.
Would this work? Is there a better way of achieving local storage and retaining the ability to share storage among hosts and migrate VMs?
Have you thought about using glusterfs? If hosts are physically close, that would probably be the best solution. -- Tony Albers Systems administrator, IT-development Royal Danish Library, Victor Albecks Vej 1, 8000 Aarhus C, Denmark. Tel: +45 2566 2383 / +45 8946 2316
On 30/04/18 12:51, Tony Brian Albers wrote:
On 30/04/18 11:43, Eduardo Mayoral wrote:
Hi,
I would like to set up a new oVirt deployment with hosts that have the VMs running on local attached storage. I understand this has the requirement of having each host in its own cluster (and own datacenter, it seems, I understand the need for the dedicated cluster, not so much for the dedicated datacenter).
At the same time, I would like to have some shared storage domains so I can use it to export VMs or migrate them around hosts (probably in three stages, first migrate VM storage from local to the shared storage domain, second migrate the host (probably not possible to do a "hot" migration, but at least "cold"), third migrate the VM storage from the shared storage domain to the local storage domain of the new host).
So I thought maybe I can deploy a datacenter in shared storage mode, with one cluster per host. Use one or two shared storage domains for master and as an stage area for planned VM migrations as explained before, and then configure several storage domains, one per host, as posix FS . I would then deploy the VMs on the local posix FS storage domains and set affinity rules for the VMs to their hosts as needed.
Would this work? Is there a better way of achieving local storage and retaining the ability to share storage among hosts and migrate VMs?
Have you thought about using glusterfs? If hosts are physically close, that would probably be the best solution.
Actually, yes, I also had glusterfs in mind. However one of the main reasons to use local storage is performance, and I am concerned about the write latencies of gluster (If using gluster, I would handle things so the VM runs on one of the gluster nodes hosting the VM data, so I assume the read latency will be close to the one I would get with local storage, but the gluster replica(s) will be on other hosts, so write latency may be significantly worse). Thanks a lot for the suggestion, it is a good one, however, the original question stands: Would this work? Is there a better way of achieving local storage and retaining the ability to share storage among hosts and migrate VMs? Best regards, -- Eduardo Mayoral.
On Mon, Apr 30, 2018 at 2:01 PM, Eduardo Mayoral <emayoral@arsys.es> wrote:
On 30/04/18 12:51, Tony Brian Albers wrote:
On 30/04/18 11:43, Eduardo Mayoral wrote:
Hi,
I would like to set up a new oVirt deployment with hosts that have the VMs running on local attached storage. I understand this has the requirement of having each host in its own cluster (and own datacenter, it seems, I understand the need for the dedicated cluster, not so much for the dedicated datacenter).
At the same time, I would like to have some shared storage domains so I can use it to export VMs or migrate them around hosts (probably in three stages, first migrate VM storage from local to the shared storage domain, second migrate the host (probably not possible to do a "hot" migration, but at least "cold"), third migrate the VM storage from the shared storage domain to the local storage domain of the new host).
So I thought maybe I can deploy a datacenter in shared storage mode, with one cluster per host. Use one or two shared storage domains for master and as an stage area for planned VM migrations as explained before, and then configure several storage domains, one per host, as posix FS . I would then deploy the VMs on the local posix FS storage domains and set affinity rules for the VMs to their hosts as needed.
Would this work? Is there a better way of achieving local storage and retaining the ability to share storage among hosts and migrate VMs?
Have you thought about using glusterfs? If hosts are physically close, that would probably be the best solution.
Actually, yes, I also had glusterfs in mind. However one of the main reasons to use local storage is performance, and I am concerned about the write latencies of gluster (If using gluster, I would handle things so the VM runs on one of the gluster nodes hosting the VM data, so I assume the read latency will be close to the one I would get with local storage, but the gluster replica(s) will be on other hosts, so write latency may be significantly worse).
Thanks a lot for the suggestion, it is a good one, however, the original question stands: Would this work? Is there a better way of achieving local storage and retaining the ability to share storage among hosts and migrate VMs?
Hi Eduardo, We support shared storage domains in a local data center since oVirt 4.1. Will this help you by any chance?
Best regards,
-- Eduardo Mayoral. _______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
participants (3)
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Eduardo Mayoral -
Maor Lipchuk -
Tony Brian Albers