Dual-room link: [1] IBM and Cisco: Together for a World Class Data Center, Page 141. http://books.google.fr/books?id=DHjJAgAAQBAJ&pg=PA141#v=onepage&q&f=false
> -----Message d'origine----- > De : Khanh-Toan Tran [mailto:khanh-toan.t...@cloudwatt.com] > Envoyé : jeudi 3 avril 2014 17:22 > À : OpenStack Development Mailing List (not for usage questions) > Objet : RE: [openstack-dev] [Nova] Hosts within two Availability Zones : possible > or not ? > > +1 for AZs not sharing hosts. > > Because its the only mechanism that allows us to segment the datacenter. > Otherwise we cannot provide redundancy to client except using Region which is > dedicated infrastructure and networked separated and anti-affinity filter which > IMO is not pragmatic as it has tendency of abusive usage. Why sacrificing this > power so that users can select the types of his desired physical hosts ? The latter > can be exposed using flavor metadata, which is a lot safer and more controllable > than using AZs. If someone insists that we really need to let users choose the > types of physical hosts, then I suggest creating a new hint, and use aggregates > with it. Dont sacrifice AZ exclusivity! > > Btw, there is a datacenter design called dual-room [1] which I think best fit for > AZs to make your cloud redundant even with one datacenter. > > Best regards, > > Toan > > > -----Message d'origine----- > > De : Chris Friesen [mailto:chris.frie...@windriver.com] > > Envoyé : jeudi 3 avril 2014 16:51 > > À : openstack-dev@lists.openstack.org > > Objet : Re: [openstack-dev] [Nova] Hosts within two Availability Zones > > : possible or not ? > > > > On 04/03/2014 07:51 AM, Sylvain Bauza wrote: > > > Hi, > > > > > > I'm currently trying to reproduce [1]. This bug requires to have the > > > same host on two different aggregates, each one having an AZ. > > > > > > IIRC, Nova API prevents hosts of being part of two distinct AZs [2], > > > so IMHO this request should not be possible. > > > That said, there are two flaws where I can identify that no > > > validation is done : > > > - when specifying an AZ in nova.conf, the host is overriding the > > > existing AZ by its own > > > - when adding an host to an aggregate without AZ defined, and > > > afterwards update the aggregate to add an AZ > > > > > > > > > So, I need direction. Either we consider it is not possible to share > > > 2 AZs for the same host and then we need to fix the two above > > > scenarios, or we say it's nice to have 2 AZs for the same host and > > > then we both remove the validation check in the API and we fix the > > > output issue reported in the original bug [1]. > > > > Currently host aggregates are quite general, but the only ways for an > > end-user to make use of them are: > > > > 1) By making the host aggregate an availability zones (where each host > > is only supposed to be in one availability zone) and selecting it at > > instance creation time. > > > > 2) By booting the instance using a flavor with appropriate metadata > > (which can only be set up by admin). > > > > > > I would like to see more flexibility available to the end-user, so I > > think we should either: > > > > A) Allow hosts to be part of more than one availability zone (and > > allow selection of multiple availability zones when booting an > > instance), or > > > > B) Allow the instance boot scheduler hints to interact with the host > > aggregate metadata. > > > > 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