Use zone to filter PowerVS service instance

[dharaneeshvrd]

What this PR does / why we need it:

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged): Fixes #1839

Special notes for your reviewer:

/area provider/ibmcloud

1. Please confirm that if this PR changes any image versions, then that's the sole change this PR makes.

Release note:

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[dharaneeshvrd]

Problem I faced is, let's say there is an existing powervs instance called capi-dhar-serviceInstance in osa21 zone. When I try to deploy new cluster with same name capi-dhar in dal12 zone, instead of creating a new powervs instance in dal12, it tries to use the one in osa21 since the it's having same name. It won't hit this, since there no two matching instances in this situation.

Also within the same zone we can't have the same service instance right?

But for this unfortunately it still allows duplicate within zone too.

[Karthik-K-N]

Problem I faced is, let's say there is an existing powervs instance called capi-dhar-serviceInstance in osa21 zone. When I try to deploy new cluster with same name capi-dhar in dal12 zone, instead of creating a new powervs instance in dal12, it tries to use the one in osa21 since the it's having same name. It won't hit this, since there no two matching instances in this situation.

Also within the same zone we can't have the same service instance right?

But for this unfortunately it still allows duplicate within zone too.

Got the point now, Thank you.

[mkumatag]

But for this unfortunately it still allows duplicate within zone too.

This is exactly my doubt too, we can't foolproof 100% here in this case, we need to mention somewhere in the api spec saying that if multiple instance with same name present then it will pick first in the list and if user wants to use any specific one then use by ID

[dharaneeshvrd]

Updated the ServiceInstance field's description, ptal!

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dharaneeshvrd, mkumatag

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