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#openstack-nova - 2026-09-04
18:41:26 gouthamr yes, mappings
18:42:13 sean-k-mooney sure but as the questions i have been asking imply i have not been folloing the overall work closely
18:42:18 melwitt yeah so it would be get all share mappings for a list of instance uuids rather than doing one by one right
18:42:26 sean-k-mooney but i agree the scalaiblity of the current approch is concerning
18:42:29 gouthamr yeah.. the data model was forcing me with some of these calls in the code.. I'm working on your suggestions to stitch (InstanceList + MigrationList + ShareMappingList) and get a list to parse... one remotable RPC that does all this would help cleanly for sure. but, can i do that in Indri? or would you prefer to have it done now?
18:45:36 melwitt adding a ShareMappingList.get_by_instance_uuids() would be simple enough. do we need more than that?
18:45:52 dansmith gouthamr: what you just described is what I just said we should do in my comment just now
18:46:15 sean-k-mooney or ShareMappingList.get_by_migration_host ?
18:46:46 dansmith gouthamr: I don't think we can/should merge this the way it is, but it would suck to have to punt it all to indri as well.. since you'll have to add RPC changes it won't be backportable either
18:47:00 dansmith melwitt: instance uuids is not enough and it's not even the likely larger list
18:47:02 gouthamr yeah no.. i wasn't looking to backport this stuff
18:47:48 gouthamr its super important for me though to make forward progress on the cold migration :( it makes all of this partially usable before we fix up the hard block on other instance actions that you folks pointed out at the PTG
18:48:20 gouthamr the backport was just going to be for: https://review.opendev.org/c/openstack/nova/+/1001900/
18:48:26 dansmith yup
18:48:31 gouthamr s/backport/backport request :)
18:49:41 gouthamr ty for this discussion and the comments!
18:53:15 sean-k-mooney gouthamr: i have not looked at https://review.opendev.org/c/openstack/nova/+/1001900 in detail but just looking at the tile im not sure that is backportable
18:53:56 gouthamr sean-k-mooney: oh, read on :P yes, we're moving auth, but it doesn't break anything running until you choose
18:54:11 sean-k-mooney it might be but we have to supprot n-2 compatiblity
18:54:15 gouthamr sean-k-mooney: this will be supplemented with an OSSN/operator guidance on how the move will occur
18:55:16 sean-k-mooney so we need atuth to work with a patched souce node and unpatch dest
18:55:20 sean-k-mooney as an example
18:55:37 sean-k-mooney its too late on a friday for me to really ingest the details
18:55:56 gouthamr sean-k-mooney: it will; on the unpatched destination, we'll use a "shared credential" until that's patched some day
18:56:32 gouthamr sean-k-mooney: yes :) ty for the brainstorm! have a great weekend
18:57:44 dansmith sean-k-mooney: it's really not ideal, I've already raised the concerns
18:58:13 sean-k-mooney ack, im not really sure that shareing a cephx id is a problme
18:58:17 dansmith sean-k-mooney: the virtiofs implementation in the tree is sort of "so leaky that it doesn't break upgrades" which is not good but also means that we _can't_ do automatic cleanup there anyway
18:58:22 sean-k-mooney but i woudl have to read the bug to knwo why it woudl be
18:58:33 dansmith sean-k-mooney: it's a hardening thing
18:59:01 sean-k-mooney sure but for nova rbd driver we mostly use the same cephx key
18:59:07 sean-k-mooney technially it can vary per host
18:59:14 sean-k-mooney but i dont really knwo of any installer that does that
18:59:37 sean-k-mooney we just use a single nova key on all compute nodes
19:00:32 sean-k-mooney so using shared ceph keyrings between host is not generally a sefutiy issue but i dont really have an object to hardening
19:01:06 dansmith I'm not sure our bad behavior is a justification to do it badly.. but those ceph shares are less user-visible than these I think
19:01:20 dansmith and the current implementation sort of can't even track which hosts should and should not have access to a share as a result
19:01:44 sean-k-mooney ack as i said i have no real issue with hardenign
19:01:58 sean-k-mooney jsut notign that it not the same as nova provisend rbd voluems
19:02:11 sean-k-mooney i think for cidner we are given a cephx key in teh conenciton info to ues
19:02:16 sean-k-mooney possibel per voluem?
19:02:50 sean-k-mooney and as i said ther is nothign prventign you minting a per host key for images_type=rbd today
19:03:21 sean-k-mooney but ya as you said if you have escaped to the host your already have other compomise vector to worry about
19:07:07 sean-k-mooney for the peroupus of share attachment the client of the sheare was desiged to be nova rather then the instnace
19:07:47 sean-k-mooney the same way as nova is the sincel client for ceph voleusm for images_type=rbd
19:07:53 dansmith that's how the code is designed now, but I think that was probably wrong
19:08:26 sean-k-mooney it depend on your pesertive of who own the expore the end user or nova
19:08:35 sean-k-mooney if its nova which is howe we desgiend it its correct
19:08:40 dansmith treating all of nova as a single unit is a bad idea, whether it be shares, volumes, access to the MQ or DB, etc.. in 2010 I think that was a lot more normal but today it seems verging on irresponsible to me
19:08:48 gouthamr ++
19:08:58 sean-k-mooney if its the end user then the cephex key shoudl be in barbican liek cinder encyption keys
19:09:49 sean-k-mooney right as i said im oke with hardenign but that feels mroe like a security feature then soemthign we would activly backport
19:10:02 gouthamr cephfs != rbd, for RBD, cephx is one of several layers. For a CephFS share, the cephx access rule is the access-control layer..
19:10:09 dansmith it is and you could surely argue that it's not backport-worthy IMHO
19:10:35 gouthamr even there though, we could make a better choice than having a single shared credential, imo..
19:11:01 sean-k-mooney gouthamr: we dont require it to be shared in nova today taht up to the installer
19:11:02 melwitt so are we thinking a separate patch for the ShareMappingList.get_share_ids_for_host() to go in front of the reconcile patch?
19:11:27 gouthamr melwitt: i'll fold it in..
19:11:37 melwitt to try and minimize churn on the reconcile? ok
19:11:48 gouthamr sean-k-mooney: ack, yes, but in this case, it's hardcoded so worse :(
19:12:12 gouthamr melwitt: it was the last patch in the series, so i can fix it up in isolation :)
19:13:31 gouthamr dansmith: i'm exploring psutil.disk_partitions.. i see its being used by quobyte: https://opendev.org/openstack/nova/src/branch/master/nova/virt/libvirt/volume/quobyte.py#L112
19:14:04 dansmith gouthamr: aha, nice
19:14:06 gouthamr dansmith: it solves my problem of not hemorrhaging on an inaccessible hard mount
19:16:13 dansmith so realistically here.. unfortunately monday is a holiday for many of us
19:16:29 dansmith I wish Uggla was around but I assume merging this on tuesday is pretty dang late
19:16:48 dansmith I almost wish melwitt had been less of a responsible person and sent the bottom patches to the gate already :)
19:17:54 sean-k-mooney so realsticlly , we cut rc1 without this next week, we can still merge this on master it just will be for next cycel if we reapprove the spec
19:18:14 sean-k-mooney and we can repprose that already
19:18:26 dansmith I have no plans for this weekend other than recharging my brokenness.. I'm not really up for reviewing tomorrow but I guess I could come back later today if it happens that it's all ready
19:19:21 dansmith but it's feeling pretty rushed for sure
19:20:22 melwitt I can also review if updated today
19:21:11 melwitt and I can check up on it over the weekend
19:21:46 gouthamr from my (probably biased) vantage point, the reconciliation of rules because we're trying not to wedge instances on cold migration is good hardening.. cold migration will be used no doubt if we shipped this even without the reconciliation - but, we're doing this right and i wouldn't do it differently..
19:22:59 gouthamr I know of a few <redacted> clouds that would be happy to have this feature land in H.. but they're all really waiting for a day their can hot-attach cephfs and call it a day - it's killing their cloud right now when person 100001 is coming to them to enable this, and they have to tell them they'd have to roll out their own tenant-scoped ceph cluster
19:23:16 dansmith gouthamr: we also know the reconciliation will not be backportable if it becomes more of a problem than you think
19:23:24 gouthamr yes
19:23:36 melwitt yeah, that's the problem, reconcile would not be backportable
19:23:53 dansmith IME instances wedged in the middle of migrations is not that uncommon so I'm nervous about having no path for cleanup for something users can trigger
19:24:49 gouthamr ack; i'll flush this out and test it and have something for your eyes in a bit.. the psutil change was the simplest :) but, the share mapping object update, i'll deep-test
19:25:09 melwitt that is my experience also. maybe the biggest complaint about nova is stuff stuck in a state requiring manual database intervention to recover
19:25:16 dansmith yup
19:25:36 dansmith gouthamr: okay then I'll take a break for a bit so I can be available for a bit later
19:25:49 gouthamr ack, thank you dansmith!
19:25:55 gouthamr same, melwitt and sean-k-mooney!
20:07:02 opendevreview Goutham Pacha Ravi proposed openstack/nova master: Reconcile stale Manila share access rules https://review.opendev.org/c/openstack/nova/+/1001916
20:07:03 opendevreview Goutham Pacha Ravi proposed openstack/nova master: Only load same-host instances when checking share usage https://review.opendev.org/c/openstack/nova/+/1004057
20:39:42 gouthamr s
21:10:35 dansmith melwitt: looks okay to me
21:16:25 gouthamr dansmith: do you mind me folding follow up comments into a single commit post these merging
21:16:39 gouthamr like a low-risk follow up that'll land next week?
21:16:48 dansmith which comments?
21:17:22 gouthamr you're right about "is_mounted()".. it's a mount path that we're check
21:17:25 gouthamr checking*
21:17:35 dansmith oh yeah that's why I said "not critical to fix right now"
21:18:07 gouthamr ++ ack, ty will watch for melwitt's comments as well
21:39:29 melwitt will be looking
21:42:14 gmaan dansmith: thanks for review on task tracking fix, I replied to your commment https://review.opendev.org/c/openstack/nova/+/1003386/comments/25784b40_6a5b7aad
21:42:27 gmaan if we are ok to do RPC versioning bupm,
21:43:22 gmaan * RPC version bump, then i can add a new RPC cast to end the task which will not impact the dest rollback for old compute mixed env

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