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#openstack-nova - 2017-04-11
18:49:07 dansmith and when I say every fifteen minutes I mean "for 14 minutes total until smoke"
18:49:47 mordred dansmith: since cloud-init does support config-drive, i'd LOVE it if nova just defaulted config-drive to on, removed the option to turn it off, and then removed the ec2 metadata service
18:50:07 dansmith yeah, the only problem is the staticness of it
18:50:12 mordred dansmith: but I suppose that's at odds with my stance about not changing things, so maybe I'm a hypocrit :)
18:50:16 dansmith i.e. volume attach and nic attach
18:50:40 mordred right- so ...
18:50:55 jaypipes lmao
18:51:21 mordred network attach should just work, since clouds should just be offering dhcp, which means there is no need for config-drive to be updated (unless the cloud is broken)
18:51:36 dansmith mordred: unless you want/need metadata about that nic
18:52:06 mordred but if you're adding a NIC after boot, you're adding the nic, so you as the orchestrator likely already know you're doing it and should be able to direct the instance to do something different,no?
18:52:37 dansmith unless you have an agent that looks for nics with tags of "multipath-to-db" and enslaves them into a bond,
18:52:40 mordred I mean, the only reason we need config-drive for network info anyway is for clouds without dhcp - for the rest I recommend using your orchestration tool to talk to the nova api
18:52:50 dansmith not necessarily
18:52:53 jaypipes mordred: right, unless you're a VNFM or MANO system that is dynamically swapping metadata about your workload's vNICs at runtime and having the workload reconfigure service function chains.
18:53:07 dansmith that ^
18:53:50 mordred I'm still not sure why that isn't just an API call on the service API - which would of course be hard because we haven't bothered with per-instance credentials :)
18:53:50 dansmith jaypipes: it does kinda sound like a chemical
18:54:24 jaypipes mordred: bingo.
18:54:29 mordred but ec2 metadata services is a poor workaround for having an agent in an instance just make API calls to the control plane in a sane fashion
18:54:46 jaypipes mordred: also correct.
18:55:30 dansmith so you want the instance to hit the api, find out the ports that are on the instance, and corellate them all by mac address to know what to do with which actual device in the OS?
18:55:56 mordred dansmith: well, the list ports call also lists the mac addresses of the ports
18:56:02 mordred but yah - I do that for every instance we spin up in nodepool
18:56:16 mordred because I have to to figure out if the instance needs a floating ip or not
18:56:42 mordred so sure!
18:57:13 dansmith that works if you've got creds in the instance
18:57:29 mordred we could also just have an API call that gives a rollup report similar to what's in the metadata service - I'm just saying it doesn't need to be a special network port that's only usable to talk to the special service that doesn't scale
18:57:37 mordred and instead we should focus on getting creds into the instance
18:57:47 mordred which would make many people happy
18:58:29 dansmith well, I dunno, given where we are, tags on the devices we add seems like a reasonable thing to me
18:58:42 dansmith especially given that there are some devices for which there is no service to talk to
18:58:46 dansmith like a raw pci device
18:59:15 mordred wouldn't that raw pci device be there at boot? or be a thing you added to the vm via nova?
18:59:16 dansmith if cinder gives us the serial number of the block device that we're going to add or something, then I guess we can do the same for cinder,
18:59:22 dansmith but otherwise that's a problem
18:59:43 mordred I mean - I hear you
18:59:45 dansmith mordred: what does it matter if it was there at boot?
19:00:04 mordred if it's there at boot, it can have data in config-drive without any issues
19:00:23 mordred the static nature of config-drive and dynamic devices was the issue
19:00:34 dansmith sure, I thought we were talking about not needing metadata at al
19:00:38 mordred oh golly no
19:00:41 mordred metadata is great
19:00:43 dansmith cinder doesn't show me a device serial number or aything,
19:00:51 dansmith so not sure that I can do the same correlation inside the guest for it
19:00:57 mordred well, mounting volumes is hard no matter what
19:01:09 mordred because how they're presented to the guest varies by hypervisor
19:01:22 mordred and the api can lie to you about the device name
19:01:24 dansmith well, same for nic, except we have an address in the case of ethernet
19:01:39 mordred dansmith: WHAT ABOUT TOKEN RING???
19:01:47 dansmith mordred: indeed, what about token ring indeed,
19:01:55 dansmith but while you say that,
19:02:04 dansmith there are definitely requests for weird custom L2 things
19:02:15 mordred oh, I'm sure there are
19:02:15 dansmith at which I laugh, but..
19:03:13 mordred so ... my world view has given up on magical agents sitting inside of guests looking for metadata updates to automagically reconfigure themselves
19:03:20 mordred that might color my opinion on how these things should work
19:03:41 dansmith well, in that case you don't really need instance creds, right?
19:03:56 mordred having systems that sit outside of the guests, that konw what's going on and that can reach in and execute commands in the guests works much better in my world so far
19:04:03 mordred dansmith: that is correct, I do not
19:04:23 dansmith anyway, I just think that being consistent about how you plumb things at boot or after boot requires metadata, and I like configdrive for that for all cases other than that it can't be updated after boot
19:04:25 mordred however, if instance creds are there, then in-instance things have access to the same power I have while sitting outside of the guest
19:04:36 mordred dansmith: ++
19:04:57 mordred and I'd like more metadata - especially in cases where our current metadata is missing or lies
19:05:07 mordred "this is the volume you named bob"
19:05:07 openstackgerrit Chris Dent proposed openstack/nova master: [placement] Idempotent PUT /resource_classes/{name} https://review.openstack.org/448791
19:05:19 dansmith mordred: right and we have that now, but only at boot for configdrive
19:05:23 dansmith the volume thing I mean
19:05:32 dansmith because we can generate that data only in the hypervisor driver
19:05:39 mordred dansmith: we ALSO have the volume thing in libvirt with device names
19:05:48 dansmith and because it's virt-specific, we only show that to the guest not the external API
19:05:59 dansmith mordred: not with volume tags which we now have
19:06:12 dansmith mordred: now you get a metadata blob that says "your vdb IS the volume you tagged as foo"
19:06:37 mordred and that tag does't show up in /dev/disk?
19:06:53 dansmith meaning /dev/disk/by-tag/?
19:07:05 mordred yah
19:07:07 dansmith something in the guest would have to do that for us, of course
19:08:10 mordred we get labels for normal cinder volumes now though - but I guess a disk can only have one lable and could have many tags
19:08:27 dansmith we get labels if they lay a filesystem down, right?
19:08:57 mordred we get a by-$something thathas the volume name in somewhere - one sec, lemme find the thing I'm talking about
19:09:35 dansmith I don't think so
19:09:46 dansmith that would be by-label, and if they put a filesystem in and labeled it
19:10:13 dansmith or are you talking about the virtio-$neutered_uuid ?
19:12:04 mordred dansmith: ok. I think I may just be smoking crack
19:12:11 dansmith I would totally believe that
19:12:13 dansmith :)
19:12:30 mordred dansmith: it's 19:12 UTC, which everyone knows is crack-o'clock
19:12:38 dansmith obvi
19:16:27 mordred of course!
19:16:40 mordred dansmith: is there some other type I should know about?
19:16:54 dansmith mordred: nah, stick to the safe stuff
19:18:56 openstackgerrit Matt Riedemann proposed openstack/nova master: Deprecate CONF.api.allow_instance_snapshots https://review.openstack.org/455100
19:27:42 openstackgerrit Mathieu Gagné proposed openstack/nova-specs master: Nova support for attached volume extend https://review.openstack.org/453272
19:35:09 mgagne gibi: mriedem asked me to ask you about your input/opinion on notification impact on this proposed spec: https://review.openstack.org/#/c/453272/
19:35:23 mgagne gibi: in PS3: "Hmm, this seems like something for which we should send a notification. I don't think we send notifications for any external events that we handle today though. It might be worth talking to gibi about this. I wouldn't block this spec on it, but it seems useful."
19:39:28 cfriesen does anything test with "force_raw_images" set to false, or with glance image formats other than raw/qcow2 ?
19:41:00 mriedem of course not http://codesearch.openstack.org/?q=force_raw_images&i=nope&repos=nova
19:41:12 mriedem that reminds me, i noticed we don't test with that as False once
19:43:51 cfriesen it seems to work okay for raw/qcow2, but apparently it doesn't work with a vmdk format image file. (admittedly a qcow2 image with a vmdk backing file is a bit odd, but we don't do anything to prevent it)
19:45:41 mriedem cfriesen: did you mean integration test? because we don't even test that with a unit test
19:45:55 mriedem vmdk with libvirt imagebackend?

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