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We conclude by investigating in more detail the link between PV and PVC. In particular, we deepen the concepts of binding and storage object in Use Protection.
Binding
For the union between PV and PVC, two of the parameters described above must be in agreement: storage and access mode.
If the PVC requires more memory than the one made available by the PV, the binding does not take place and will remain unbound indefinitely if a matching volume does not exist. Likewise, if the access mode of the two components are not compatible, they will remain unconnected. I used the term compatible, because the two values don't necessarily have to be the same. In some providers, the binding can still take place if the PVC requires a lower level of permissions (eg. RWO) than that of the PV (eg. RWX).
We have said that the bond between PV and PVC is one-to-one. Therefore if the PVC requires, for example, 5Gi and the PV makes 8Gi available, there is a "waste" of 3Gi. Unfortunately, this can happen in the case of static provisioning. Dynamic mode is more "economical", because the PV is sewn exactly to the requirements of the PV.