umbrella issue: deprecating zones in Cluster API

[RainbowMango]

What would you like to be added:
This issue tracks subsequent tasks of deprecating zone with zones.

• Add validation for zones, possibly at here. (@zishen, Add validation for zones #3975)
  In addition, we should ensure that zone and zones will not co-exist.
• Transform potential zone to zones, possibly at here. (@zishen, transform zone to zones #3983)
• Deprecate the --cluster-zone flag of join and introduce a new flag --cluster-zones. (@whitewindmills, feat: deprecate cluster-zone flag and introduce cluster-zones flag #3995)
• Adopt zones in scheduler spread by constraints, possibly at here. (@zishen, feat: adopt zones in scheduler spread by constraints #4002)
• Adopt zones in scheduler filter, possibly at here. (@whitewindmills, feat: adapt zones check in spread constraint plugin #3996)
• Adopt zones in resource selector, possibly at here (@whitewindmills, adopt zones in resource selector #4010)

Why is this needed:

[whitewindmills]

Adopt zones in scheduler spread by constraints

maybe we don't need this task because zone spread constraint has not been supported in the master branch. I'll consider zones fields in the new spread-constraint pr.

[RainbowMango]

Adopt zones in resource selector,

What about this one?

Adopt zones in scheduler filter

This one might be a challenge too.

[whitewindmills]

others look good to me.

[zishen]

I'm interested in this, too. How about I contribute Add validation for zones and Transform potential zone to zones?
@whitewindmills

[RainbowMango]

@zishen Please go for it.

[whitewindmills]

Adopt zones in resource selector

I'm about to complete this task but have an ambiguous problem. For example, zones of cluster member1 are zone-a,zone-b,zone-c.

1. I use such cluster affinity: zone NotIn [zone-a zone-b], does cluster member1 match it?
2. I use such cluster affinity: zone In [zone-a zone-b], does cluster member1 match it?

[RainbowMango]

That's a good question and I don't have a clue yet.
What's your opinion then?

[whitewindmills]

question 1 & 2 are both match cluster member1. only zone NotIn [zone-a zone-b zone-c] cannot match it. what do you think of this rule?

[RainbowMango]

My concern is that if the user wants to propagate a resource to a cluster that requires the cluster in a specific zone.
For the example above, he/she requires a cluster in zone-a, if the scheduler selects member1, we can't guarantee the resource would be scheduled to the node in zone-a.

Obviously, we need to do something about that. But before that, I'd like to take an exact match.

For your answers, I tend to Q1 and Q2 do not match.

[whitewindmills]

Maybe we can add a field to give the user the choice of whether to match exactly, For example:

clusterAffinity:
  fieldSelector:
    matchExpressions:
    - key: zone
      operator: In
      values:
      - zone-a
      - zone-b
  zoneMatchBehavior: Exactly

[RainbowMango]

Maybe we can add a field to give the user the choice of whether to match exactly,

Will see. That's an option for the future.

[whitewindmills]

Obviously, we need to do something about that. But before that, I'd like to take an exact match.

okay, let's implement it this way for now.

[RainbowMango]

Many thanks to @whitewindmills @zishen for the help, all tasks have been finished.
/assign @whitewindmills @zishen
/close

[karmada-bot]

@RainbowMango: Closing this issue.

In response to this:

Many thanks to @whitewindmills @zishen for the help, all tasks have been finished.
/assign @whitewindmills @zishen
/close

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