Re: [openstack-dev] inconsistent naming? node vs host vs vs hypervisor_hostname vs OS-EXT-SRV-ATTR:host
> -Original Message- > From: Chris Friesen [mailto:chris.frie...@windriver.com] > Sent: Friday, February 28, 2014 10:07 AM > To: openstack-dev@lists.openstack.org > Subject: Re: [openstack-dev] inconsistent naming? node vs host vs vs > hypervisor_hostname vs OS-EXT-SRV-ATTR:host > > On 02/28/2014 11:38 AM, Jiang, Yunhong wrote: > > One reason of the confusion is, in some virt driver (maybe xenapi or > > vmwareapi), one compute service manages multiple node. > > Okay, so in the scenario above, is the nova-compute service running on a I think the nova compute service runs on a host, as you can see from compute/manager.py and manager.py. > "node" or a "host"? (And if it's a "host", then what is the "compute > node"?) Check the update_available_resource() at compute/manager.py for the node idea. > > What is the distinction between "OS-EXT-SRV-ATTR:host" and > "OS-EXT-SRV-ATTR:hypervisor_hostname" in the above case? According to _extend_server() at ./api/openstack/compute/contrib/extended_server_attributes.py, the "OS-EXT-SRV-ATTR:hypervisor_hostname is the node and the "OS-EXT-SRV-ATTR:host" is the host. I agree this is a bit confusing, especially the document is not clearly, I'd call the " OS-EXT-SRV-ATTR:hypervisor_hostname" as " OS-EXT-SRV-ATTR:hypervisor_nodename", which makes more sense and more clearly. Per my understanding with the xenapi, there is a hypervisor on each compute node, and XenAPI (or any name for that software layer) manage multiple (or 1 in extreme case) nodes, that XenAPI software layer interact with nova service and is like a host from nova point of view. Dan has some interesting discussion on the Nova meet up on this and the cell (so called cloud NUMA IIRC?) Thanks --jyh > > Chris > > ___ > OpenStack-dev mailing list > OpenStack-dev@lists.openstack.org > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev ___ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
Re: [openstack-dev] inconsistent naming? node vs host vs vs hypervisor_hostname vs OS-EXT-SRV-ATTR:host
On 02/28/2014 11:38 AM, Jiang, Yunhong wrote: One reason of the confusion is, in some virt driver (maybe xenapi or vmwareapi), one compute service manages multiple node. Okay, so in the scenario above, is the nova-compute service running on a "node" or a "host"? (And if it's a "host", then what is the "compute node"?) What is the distinction between "OS-EXT-SRV-ATTR:host" and "OS-EXT-SRV-ATTR:hypervisor_hostname" in the above case? Chris ___ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
Re: [openstack-dev] inconsistent naming? node vs host vs vs hypervisor_hostname vs OS-EXT-SRV-ATTR:host
One reason of the confusion is, in some virt driver (maybe xenapi or vmwareapi), one compute service manages multiple node. --jyh > -Original Message- > From: Chris Friesen [mailto:chris.frie...@windriver.com] > Sent: Friday, February 28, 2014 7:40 AM > To: openstack-dev@lists.openstack.org > Subject: [openstack-dev] inconsistent naming? node vs host vs vs > hypervisor_hostname vs OS-EXT-SRV-ATTR:host > > Hi, > > I've been working with OpenStack for a while now but I'm still a bit > fuzzy on the precise meaning of some of the terminology. > > It seems reasonably clear that a "node" is a computer running at least > one component of an Openstack system. > > However, "nova service-list" talks about the "host" that a given service > runs on. Shouldn't that be "node"? Normally "host" is used to > distinguish from "guest", but that doesn't really make sense for a > dedicated controller node. > > "nova show" reports "OS-EXT-SRV-ATTR:host" and > "OS-EXT-SRV-ATTR:hypervisor_hostname" for an instance. What is the > distinction between the two and how do they relate to OpenStack "nodes" > or the "host" names in "nova service-list"? > > "nova hypervisor-list" uses the term "hypervisor hostname", but "nova > hypervisor-stats" talks about "compute nodes". Is this distinction > accurate or should they both use the hypervisor terminology? What is > the distinction between hypervisor/host/node? > > "nova host-list" reports "host_name", but seems to include all services. > Does "host_name" correspond to host, hypervisor_host, or node? And > just to make things interesting, the other "nova host-*" commands only > work on compute hosts, so maybe "nova host-list" should only output info > for systems running nova-compute? > > > Thanks, > Chris > > ___ > OpenStack-dev mailing list > OpenStack-dev@lists.openstack.org > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev ___ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
[openstack-dev] inconsistent naming? node vs host vs vs hypervisor_hostname vs OS-EXT-SRV-ATTR:host
Hi, I've been working with OpenStack for a while now but I'm still a bit fuzzy on the precise meaning of some of the terminology. It seems reasonably clear that a "node" is a computer running at least one component of an Openstack system. However, "nova service-list" talks about the "host" that a given service runs on. Shouldn't that be "node"? Normally "host" is used to distinguish from "guest", but that doesn't really make sense for a dedicated controller node. "nova show" reports "OS-EXT-SRV-ATTR:host" and "OS-EXT-SRV-ATTR:hypervisor_hostname" for an instance. What is the distinction between the two and how do they relate to OpenStack "nodes" or the "host" names in "nova service-list"? "nova hypervisor-list" uses the term "hypervisor hostname", but "nova hypervisor-stats" talks about "compute nodes". Is this distinction accurate or should they both use the hypervisor terminology? What is the distinction between hypervisor/host/node? "nova host-list" reports "host_name", but seems to include all services. Does "host_name" correspond to host, hypervisor_host, or node? And just to make things interesting, the other "nova host-*" commands only work on compute hosts, so maybe "nova host-list" should only output info for systems running nova-compute? Thanks, Chris ___ OpenStack-dev mailing list OpenStack-dev@lists.openstack.org http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
