16:00:01 #startmeeting cinder-nova-api-changes 16:00:02 Meeting started Thu May 4 16:00:01 2017 UTC and is due to finish in 60 minutes. The chair is ildikov. Information about MeetBot at http://wiki.debian.org/MeetBot. 16:00:03 Useful Commands: #action #agreed #help #info #idea #link #topic #startvote. 16:00:05 The meeting name has been set to 'cinder_nova_api_changes' 16:00:07 o/ 16:00:10 o/ 16:00:11 DuncanT ameade cFouts johnthetubaguy jaypipes takashin alaski e0ne jgriffith tbarron andrearosa hemna erlon mriedem gouthamr ebalduf patrickeast smcginnis diablo_rojo gsilvis xyang1 raj_singh lyarwood breitz jungleboyj 16:00:26 o/ 16:00:30 \0 16:00:36 @! 16:00:36 hemna (╯°□°)╯︵ ┻━┻ 16:00:46 hemna: already? :) 16:00:54 yah, why not :P 16:00:56 @!h 16:00:56 jungleboyj (/ .□.) ︵╰(゜Д゜)╯︵ /(.□. ) 16:01:22 It is a good way to start any meeting. 16:01:25 pre-Summit meeting, I get it... :) 16:01:31 ok, let's start then 16:02:18 I see mriedem added a few comments to shutdown_instance 16:02:46 saw those, starting on that 16:02:53 I think local_cleanup is also ready for review: https://review.openstack.org/#/c/456851/ 16:03:02 stvnoyes: am I right? ^ 16:03:05 yes 16:04:08 mriedem: so please add comments to that one too ^^ :) 16:04:21 already doing it 16:04:56 we started to discuss migrate_volume_completion with the Cinder team and in my understanding to conclusion is to look into how to use the new calls with it 16:05:32 so we plan to keep the same call back method concept and have it covered in the new API 16:06:03 at least my expectation is that it's more clear that way, but maybe we can update the existing call easily 16:06:37 e0ne will help looking into the current version and figure out the new API (compatible) solution 16:07:00 so in this sense swap_volume in Nova is on hold currently until the Cinder side is done/fixed 16:07:32 in the meantime stvnoyes is looking into live migrate to see what the challenges are there 16:08:00 so what do you mean by the 'new' api in cinder? 16:08:12 mriedem: the new attach/detach API 16:08:16 because if migrate_volume_completion doesn't handle this for 3.27, then cinder needs a new microversion for that 16:08:50 mriedem: We still need to determine if we need a new API call or not. 16:09:01 ok 16:09:12 like, nova might not need to call migrate_volume_completion at all? 16:09:22 or you plan on doing something in 3.27 maybe to handle it if it's a new-style attachment? 16:09:28 like as a bug fix? 16:09:32 Bug fix. 16:10:31 is there an option that does not need new microversion? 16:10:42 just for my understanding :) 16:11:03 ildikov: If we can make the current call handle the new attachment correctly, then we don't need a microversion bump. 16:11:16 But if we need to add a new API, or somehow change the current one, then that will need it. 16:11:20 smcginnis, +1 16:11:33 But that's the part I am not clear on - which of those we need to do. 16:12:47 Down side being with NOT doing a microversion bump, there will be no way externally to know if the version of cinder present can handle this or not. 16:13:25 smcginnis: I just wanted to ask whether that's a bug fix to backport 16:13:45 ildikov: If we can fix the current method, then definitely we will get that backported. 16:14:15 * johnthetubaguy wonders in late and hides at the back 16:14:33 smcginnis: ok, cool, I think that was my concern 16:14:39 johnthetubaguy: hi :) 16:15:03 johnthetubaguy: we discussed swap_volume and migrate_volume_completion briefly 16:15:19 yeah, just scrolling back 16:15:43 johnthetubaguy: let us know if you have further questions or comments 16:15:55 smcginnis: do a microversion bump to just signal the new stuff is there? 16:16:17 johnthetubaguy: We could. But then we can't really backport that. 16:16:21 downside is we probably would then no want to trigger the new flow until that microversion is there 16:16:28 +1 16:16:34 yeah, I guess we just said the same thing in two different ways 16:16:39 :) 16:16:56 why would we need/want to backport it? 16:17:07 If we can do it as a bug fix and get it backported, I don't think we would have too big of a window until it's out there. 16:17:28 if we do a version bump, then we need to check that higher version when we add attach 16:17:37 ildikov: yep 16:17:42 Just to allow Ocata Cinder with Pike Nova. But then again, maybe we don't care and just make it the new required level. 16:17:45 or we do what smcginnis says 16:18:03 the silent backport sounds way too much like cheating in a way we will break things 16:18:17 smcginnis: so Nova just uses the old flow if cinder is too old, so its OK I think 16:18:32 I mean, its not idea... but life sucks sometimes 16:18:48 johnthetubaguy: Yeah. Was just hoping we had all the pieces in place to not have to do that. 16:18:51 But maybe not. 16:18:51 so cleanest option is a new API we pass the old and new attachment ids too? 16:19:12 First we need to figure out this code and understand what we actually need to do. 16:19:22 I have not touched that, and most who have recently are gone. 16:19:24 yeah before we rathole, 16:19:36 So we just need to refresh our knowledge a bit. 16:19:37 let's figure out what actually needs to happen on the cinder side for migrate_volume_completion 16:19:39 * johnthetubaguy things mriedem saw we typing 16:19:43 thinks^ 16:19:47 mriedem: +1 16:19:48 me^ 16:19:53 if it's a request body change or something, it's definitely microversion bump 16:19:56 e0ne is not around, but offered to help by having some knowledge about the current code 16:19:59 so until we sort that out, let's move on 16:20:03 +1 16:20:12 so migrate_volume_completion let get clear on what it does 16:20:32 yep, that's the plan 16:20:34 also note that we should be able to attach/detach with 3.27, 16:20:45 but maybe not swap volume until a later microversion or something; nova as client code can determine that 16:20:50 I think... it makes volume B look like volume A, we currently pass in A and B, but that only happens if the user called cinder to migrate volume A 16:21:18 if the user called nova to swap A and B, non that really happens, I am not sure if the cinder call actually does anything in that case 16:22:06 mriedem: I kinda like the one high water mark, if I am honest, makes life less complicated (please upgrade to make swap volume work with your newly attached volumes, etc) 16:22:23 Certainly safer. 16:22:29 sure, just stating options 16:22:37 but let's move on - todo is on cinder to figure out what needs to happen 16:22:38 mriedem: so that means if a volume is attached in the new way then you cannot swap that if you don't have the high enough microversion, if we go down that path 16:24:00 #action Cinder team to figure out how to handle migrate_volume_completion on the Cinder side 16:24:15 smcginnis: ildikov We are planning to get together with e0ne to talk about this next week. Right? 16:24:22 I'm ready to move on 16:24:35 Let's move on. 16:24:45 so as jungleboyj brought it up 16:24:50 jungleboyj: Yes 16:24:54 :-) 16:24:54 do we want a small sub-team gathering next week? 16:25:25 at this point I have free lunch times and break times 16:25:26 like mriedem johnthetubaguy would you be interested to join? 16:25:41 my schedule is full 16:25:53 johnthetubaguy: There's always between 11pm and 6am. :) 16:26:01 there is the Nova and Cinder forum session, we could get onto this if we "have spare time" 16:26:07 smcginnis: you and i are in customer meetings at those times 16:26:16 mriedem: Sadly true 16:26:18 there isn't a nova/cinder forum session, 16:26:29 the one you're thinking of is specifically about using cinder for ephemeral 16:26:36 and volume affinity 16:26:38 yeah, thats the one 16:26:45 those aren't this though 16:26:46 oh, so thats like 2 hours of material already 16:26:55 yeah, no spare time there 16:27:01 yeah, we could reserve a slot in a hacking room 16:27:04 :-( 16:27:08 there are spill over rooms on thursday afternoon, 16:27:37 Maybe let's just try to get a hacking room time reserved, then whoever can make it can make it. 16:27:42 ok 16:27:45 which I hope we can do with a few Cinder guys 16:28:01 i'm totally happy if the cinder team can get together and figure out all of the problems 16:28:15 smcginnis: yep, I will sync up with e0ne and try to figure out when (if) jgriffith is available 16:28:25 mriedem: :) 16:28:33 +1 16:28:46 :-) 16:29:01 ok, we can take finding a slot offline 16:29:21 stvnoyes: is there anything for live migrate to talk about here today? 16:31:01 I take it as a no :) 16:31:30 I don't have additional topics for today, I don't think it would worth going into other things before get swap and migrate figured out 16:31:40 obviously no meeting next week 16:31:47 i'm +2 on the local delete patch, 16:31:57 and the shutdown_instance one should be simple to address my -1 16:32:01 just decouple that refactor 16:32:04 mriedem: I saw, thank you 16:32:18 johnthetubaguy: if you have a minute plz check the local_cleanup patch 16:32:31 I will try look at that 16:32:45 johnthetubaguy: it's a pretty small one at least 16:32:51 johnthetubaguy: thank you 16:32:52 i can update the review priorities etherpad too 16:33:01 mriedem: sounds good, thanks 16:33:39 is it ok to have the next meeting the week after the summit? 16:33:48 ildikov: Works for me. 16:34:12 sure 16:34:16 ildikov: Yep. 16:34:44 cool, then I'll send out a mail to the ML that next week is cancelled and hopefully we will have some meet for swap to discuss two weeks from today 16:35:08 anything else from anyone for today? 16:35:18 oh btw 16:35:24 https://review.openstack.org/#/c/459113/ was updated 16:35:31 that's the attachment_update method 16:35:38 so should be good for review again 16:36:00 mriedem: awesome, thank you! 16:36:17 mriedem: I'll check after the meeting 16:36:27 yeah, me too 16:37:29 if nothing else, then thanks everyone for today 16:37:34 safe travels! 16:37:43 See you all in Boston. 16:37:45 and see you next week! :) 16:37:53 See you next week. Safe travels! 16:37:55 literally :) 16:37:55 +1 16:38:43 #endmeeting