I agree with Sean. In general terms: * A resource provider should be marked with a trait if that feature * Can be turned on or off (whether it's currently on or not); or * Is always on and can't ever be turned off. * A consumer wanting that feature present (doesn't matter whether it's on or off) should specify it as a required *trait*. * A consumer wanting that feature present and turned on should * Specify it as a required trait; AND * Indicate that it be turned on via some other mechanism (e.g. a separate extra_spec).
I believe this satisfies Dmitry's (Ironic's) needs, but also Jay's drive for placement purity. Please invite me to the hangout or whatever. Thanks, Eric On 10/23/2017 07:22 AM, Mooney, Sean K wrote: > > > > > *From:*Jay Pipes [mailto:jaypi...@gmail.com] > *Sent:* Monday, October 23, 2017 12:20 PM > *To:* OpenStack Development Mailing List <openstack-dev@lists.openstack.org> > *Subject:* Re: [openstack-dev] [ironic] ironic and traits > > > > Writing from my phone... May I ask that before you proceed with any plan > that uses traits for state information that we have a hangout or > videoconference to discuss this? Unfortunately today and tomorrow I'm > not able to do a hangout but I can do one on Wednesday any time of the day. > > > > */[Mooney, Sean K] on the uefi boot topic I did bring up at the ptg that > we wanted to standardizes tratis for “verified boot” /* > > */that included a trait for uefi secure boot enabled and to indicated a > hardware root of trust, e.g. intel boot guard or similar/* > > */we distinctly wanted to be able to tag nova compute hosts with those > new traits so we could require that vms that request/* > > */a host with uefi secure boot enabled and a hardware root of trust are > scheduled only to those nodes. /* > > */ /* > > */There are many other examples that effect both vms and bare metal such > as, ecc/interleaved memory, cluster on die, /* > > */l3 cache code and data prioritization, vt-d/vt-c, HPET, Hyper > threading, power states … all of these feature may be present on the > platform/* > > */but I also need to know if they are turned on. Ruling out state in > traits means all of this logic will eventually get pushed to scheduler > filters/* > > */which will be suboptimal long term as more state is tracked. Software > defined infrastructure may be the future but hardware defined software/* > > */is sadly the present…/* > > */ /* > > */I do however think there should be a sperateion between asking for a > host that provides x with a trait and asking for x to be configure via/* > > */A trait. The trait secure_boot_enabled should never result in the > feature being enabled It should just find a host with it on. If you want/* > > */To request it to be turned on you would request a host with > secure_boot_capable as a trait and have a flavor extra spec or image > property to request/* > > */Ironic to enabled it. these are two very different request and should > not be treated the same. /* > > > > > > Lemme know! > > -jay > > > > On Oct 23, 2017 5:01 AM, "Dmitry Tantsur" <dtant...@redhat.com > <mailto:dtant...@redhat.com>> wrote: > > Hi Jay! > > I appreciate your comments, but I think you're approaching the > problem from purely VM point of view. Things simply don't work the > same way in bare metal, at least not if we want to provide the same > user experience. > > > > On Sun, Oct 22, 2017 at 2:25 PM, Jay Pipes <jaypi...@gmail.com > <mailto:jaypi...@gmail.com>> wrote: > > Sorry for delay, took a week off before starting a new job. > Comments inline. > > On 10/16/2017 12:24 PM, Dmitry Tantsur wrote: > > Hi all, > > I promised John to dump my thoughts on traits to the ML, so > here we go :) > > I see two roles of traits (or kinds of traits) for bare metal: > 1. traits that say what the node can do already (e.g. "the > node is > doing UEFI boot") > 2. traits that say what the node can be *configured* to do > (e.g. "the node can > boot in UEFI mode") > > > There's only one role for traits. #2 above. #1 is state > information. Traits are not for state information. Traits are > only for communicating capabilities of a resource provider > (baremetal node). > > > > These are not different, that's what I'm talking about here. No > users care about the difference between "this node was put in UEFI > mode by an operator in advance", "this node was put in UEFI mode by > an ironic driver on demand" and "this node is always in UEFI mode, > because it's AARCH64 and it does not have BIOS". These situation > produce the same result (the node is booted in UEFI mode), and thus > it's up to ironic to hide this difference. > > > > My suggestion with traits is one way to do it, I'm not sure what you > suggest though. > > > > > For example, let's say we add the following to the os-traits > library [1] > > * STORAGE_RAID_0 > * STORAGE_RAID_1 > * STORAGE_RAID_5 > * STORAGE_RAID_6 > * STORAGE_RAID_10 > > The Ironic administrator would add all RAID-related traits to > the baremetal nodes that had the *capability* of supporting that > particular RAID setup [2] > > When provisioned, the baremetal node would either have RAID > configured in a certain level or not configured at all. > > > A very important note: the Placement API and Nova scheduler (or > future Ironic scheduler) doesn't care about this. At all. I know > it sounds like I'm being callous, but I'm not. Placement and > scheduling doesn't care about the state of things. It only cares > about the capabilities of target destinations. That's it. > > > > Yes, because VMs always start with a clean state, and hypervisor is > there to ensure that. We don't have this luxury in ironic :) E.g. > our SNMP driver is not even aware of boot modes (or RAID, or BIOS > configuration), which does not mean that a node using it cannot be > in UEFI mode (have a RAID or BIOS pre-configured, etc, etc). > > > > > > This seems confusing, but it's actually very useful. Say, I > have a flavor that > requests UEFI boot via a trait. It will match both the nodes > that are already in > UEFI mode, as well as nodes that can be put in UEFI mode. > > > No :) It will only match nodes that have the UEFI capability. > The set of providers that have the ability to be booted via UEFI > is *always* a superset of the set of providers that *have been > booted via UEFI*. Placement and scheduling decisions only care > about that superset -- the providers with a particular capability. > > > > Well, no, it will. Again, you're purely basing on the VM idea, where > a VM is always *put* in UEFI mode, no matter how the hypervisor > looks like. It is simply not the case for us. You have to care what > state the node is, because many drivers cannot change this state. > > > > > > This idea goes further with deploy templates (new concept > we've been thinking > about). A flavor can request something like CUSTOM_RAID_5, > and it will match the > nodes that already have RAID 5, or, more interestingly, the > nodes on which we > can build RAID 5 before deployment. The UEFI example above > can be treated in a > similar way. > > This ends up with two sources of knowledge about traits in > ironic: > 1. Operators setting something they know about hardware > ("this node is in UEFI > mode"), > 2. Ironic drivers reporting something they > 2.1. know about hardware ("this node is in UEFI mode" - > again) > 2.2. can do about hardware ("I can put this node in UEFI > mode") > > > You're correct that both pieces of information are important. > However, only the "can do about hardware" part is relevant to > Placement and Nova. > > For case #1 we are planning on a new CRUD API to set/unset > traits for a node. > > > I would *strongly* advise against this. Traits are not for state > information. > > Instead, consider having a DB (or JSON) schema that lists state > information in fields that are explicitly for that state > information. > > For example, a schema that looks like this: > > { > "boot": { > "mode": <one of 'bios' or 'uefi'>, > "params": <dict> > }, > "disk": { > "raid": { > "level": <int>, > "controller": <one of 'sw' or 'hw'>, > "driver": <string>, > "params": <dict> > }, ... > }, > "network": { > ... > } > } > > etc, etc. > > Don't use trait strings to represent state information. > > > > I don't see an alternative proposal that will satisfy what we have > to solve. > > > > > Best, > -jay > > Case #2 is more interesting. We have two options, I think: > > a) Operators still set traits on nodes, drivers are simply > validating them. E.g. > an operators sets CUSTOM_RAID_5, and the node's RAID > interface checks if it is > possible to do. The downside is obvious - with a lot of > deploy templates > available it can be a lot of manual work. > > b) Drivers report the traits, and they get somehow added to > the traits provided > by an operator. Technically, there are sub-cases again: > b.1) The new traits API returns a union of > operator-provided and > driver-provided traits > b.2) The new traits API returns only operator-provided > traits; driver-provided > traits are returned e.g. via a new field > (node.driver_traits). Then nova will > have to merge the lists itself. > > My personal favorite is the last option: I'd like a clear > distinction between > different "sources" of traits, but I'd also like to reduce > manual work for > operators. > > A valid counter-argument is: what if an operator wants to > override a > driver-provided trait? E.g. a node can do RAID 5, but I > don't want this > particular node to do it for any reason. I'm not sure if > it's a valid case, and > what to do about it. > > Let me know what you think. > > Dmitry > > > [1] http://git.openstack.org/cgit/openstack/os-traits/tree/ > [2] Based on how many attached disks the node had, the presence > and abilities of a hardware RAID controller, etc > > > > > __________________________________________________________________________ > OpenStack Development Mailing List (not for usage questions) > Unsubscribe: > openstack-dev-requ...@lists.openstack.org?subject:unsubscribe > <http://openstack-dev-requ...@lists.openstack.org?subject:unsubscribe> > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev > > > > > __________________________________________________________________________ > OpenStack Development Mailing List (not for usage questions) > Unsubscribe: > openstack-dev-requ...@lists.openstack.org?subject:unsubscribe > <http://openstack-dev-requ...@lists.openstack.org?subject:unsubscribe> > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev > > > > __________________________________________________________________________ > OpenStack Development Mailing List (not for usage questions) > Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe > http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev > __________________________________________________________________________ OpenStack Development Mailing List (not for usage questions) Unsubscribe: openstack-dev-requ...@lists.openstack.org?subject:unsubscribe http://lists.openstack.org/cgi-bin/mailman/listinfo/openstack-dev
