When attempting to create a Vertex AI endpoint with CMEK, I get:
Failed to create endpoint...The following quota metrics exceed quota limits: aiplatform.googleapis.com/in_use_customer_managed_encryption_keys' Status: 429 Error code: 429
On the Console, under "IAM and admin", "Quotas", the limit for quota "In use customer managed encryption keys per region" for the region corresponding to my endpoint, is listed as 1 and current usage as 0. Perhaps the current usage must be less than the limit?
I requested a raise in that quota limit and in the description asked whether a limit >1 was required to create a single CMEK endpoint, however the response did not address this question but rather just asked for payment to increase the quota.
Yes, it appears that the current usage must be less than the limit i.e. a limit of 1 does not allow any usage.
I successfully applied for a quota increase to raise the limit to 2 and was subsequently able to create the endpoint with the CMEK key.