Expand an ovirt+glusterfs cluster
Hello I have a 4 node oVirt 4.0 cluster running on top of glusterfs volumes, managed by the oVirt cluster (option ticked in the cluster properties) Now, I'm adding several new nodes to this cluster with a better CPU (Broadwell vs Haswell) but now comes the "bad" part. Out of enthusiasm I've already added storage from these new servers to the data volume already present and used by the current cluster. In fact now ovirt has detected new hosts and it's asking me if I want to add these host to the cluster. But there are two problems: 1) I want to create a new, Broadwell cluster 2) I'm using a separate VLAN+domain name for gluster, and oVirt is proposing me to use the gluster (storage) domain names as the new hosts identifier. What are the right steps/actions to take now? It's a running production system. Thanks in advance -- Davide Ferrari Senior Systems Engineer
I may add that as of now I've just added the bricks and nothing more, no VMs/new disks created in the oVirt cluster (in case i should remove the bricks) 2017-03-21 13:09 GMT+01:00 Davide Ferrari <davide@billymob.com>:
Hello
I have a 4 node oVirt 4.0 cluster running on top of glusterfs volumes, managed by the oVirt cluster (option ticked in the cluster properties)
Now, I'm adding several new nodes to this cluster with a better CPU (Broadwell vs Haswell) but now comes the "bad" part. Out of enthusiasm I've already added storage from these new servers to the data volume already present and used by the current cluster. In fact now ovirt has detected new hosts and it's asking me if I want to add these host to the cluster.
But there are two problems: 1) I want to create a new, Broadwell cluster 2) I'm using a separate VLAN+domain name for gluster, and oVirt is proposing me to use the gluster (storage) domain names as the new hosts identifier.
What are the right steps/actions to take now? It's a running production system.
Thanks in advance
-- Davide Ferrari Senior Systems Engineer
-- Davide Ferrari Senior Systems Engineer
Responses inline On Tue, Mar 21, 2017 at 5:42 PM, Davide Ferrari <davide@billymob.com> wrote:
I may add that as of now I've just added the bricks and nothing more, no VMs/new disks created in the oVirt cluster (in case i should remove the bricks)
2017-03-21 13:09 GMT+01:00 Davide Ferrari <davide@billymob.com>:
Hello
I have a 4 node oVirt 4.0 cluster running on top of glusterfs volumes, managed by the oVirt cluster (option ticked in the cluster properties)
Now, I'm adding several new nodes to this cluster with a better CPU (Broadwell vs Haswell) but now comes the "bad" part. Out of enthusiasm I've already added storage from these new servers to the data volume already present and used by the current cluster. In fact now ovirt has detected new hosts and it's asking me if I want to add these host to the cluster.
But there are two problems: 1) I want to create a new, Broadwell cluster
A gluster volume cannot span multiple clusters. If you want to create a separate cluster with the Broadwell nodes, then create a new gluster volume using the disks from these nodes - i.e do not expand the existing volume by adding bricks from the new servers.
2) I'm using a separate VLAN+domain name for gluster, and oVirt is
proposing me to use the gluster (storage) domain names as the new hosts identifier.
You can add hosts using the Add new host flow - and provide the FQDN that you want as management interface, and later associate the gluster VLAN with a network that has "gluster" role. Please keep in mind that you cannot add this to a new cluster in oVirt if you have already used bricks from these servers on existing volume in another cluster
What are the right steps/actions to take now? It's a running production system.
Thanks in advance
-- Davide Ferrari Senior Systems Engineer
-- Davide Ferrari Senior Systems Engineer
_______________________________________________ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
2017-03-22 8:09 GMT+01:00 Sahina Bose <sabose@redhat.com>:
Responses inline
Mines too :)
A gluster volume cannot span multiple clusters. If you want to create a separate cluster with the Broadwell nodes, then create a new gluster volume using the disks from these nodes - i.e do not expand the existing volume by adding bricks from the new servers.
Ouch, bummer :(
2) I'm using a separate VLAN+domain name for gluster, and oVirt is
proposing me to use the gluster (storage) domain names as the new hosts identifier.
You can add hosts using the Add new host flow - and provide the FQDN that you want as management interface, and later associate the gluster VLAN with a network that has "gluster" role. Please keep in mind that you cannot add this to a new cluster in oVirt if you have already used bricks from these servers on existing volume in another cluster
So, how should I create the new, dedicated gluster volume? Within oVirt or on the command line as I created the first data volume when I installed oVirt from scratch? I guess the former should work, right? But then, can I do live migrations from the lower CPU cluster to the newer one? I guess it's possible according to this: http://www.ovirt.org/develop/release-management/features/storage/live-storag... Thanks for your time -- Davide Ferrari Senior Systems Engineer
2017-03-22 8:09 GMT+01:00 Sahina Bose <sabose@redhat.com>:
A gluster volume cannot span multiple clusters. If you want to create a separate cluster with the Broadwell nodes, then create a new gluster volume using the disks from these nodes - i.e do not expand the existing volume by adding bricks from the new servers.
About this: why? I mean, from the new cluster I can spawn a VM based on an image stored in the other cluster domain and it works. What's the problem? Anyway I created a new data domain for that cluster
On Wed, Mar 22, 2017 at 8:29 PM, Davide Ferrari <davide@billymob.com> wrote:
2017-03-22 8:09 GMT+01:00 Sahina Bose <sabose@redhat.com>:
A gluster volume cannot span multiple clusters. If you want to create a separate cluster with the Broadwell nodes, then create a new gluster volume using the disks from these nodes - i.e do not expand the existing volume by adding bricks from the new servers.
About this: why? I mean, from the new cluster I can spawn a VM based on an image stored in the other cluster domain and it works. What's the problem? Anyway I created a new data domain for that cluster
Each cluster is also created as a gluster trusted storage pool - that is nodes in the cluster are peer probed to each other. A gluster volume can only span one trusted storage pool at a time.
participants (2)
-
Davide Ferrari -
Sahina Bose