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Missing details about HA on SQL Hyperscale #32251

Closed juho-hanhimaki closed 4 years ago

juho-hanhimaki commented 5 years ago

The article is missing details of high availability on Azure SQL DB Hyperscale tier.

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KalyanChanumolu-MSFT commented 5 years ago

@juho-hanhimaki Thank you for the feedback. We are reviewing the content and will get back to you shortly.

KalyanChanumolu-MSFT commented 5 years ago

@juho-hanhimaki This issue is being assigned to the content author to evaluate and update as appropriate. 

vlad-kozlov commented 5 years ago

any status update on HA for Hyperscale tier?

Mike-Ubezzi-MSFT commented 5 years ago

@vlad-kozlov Is there something specific you are looking for in the documentation pertaining to High Availability? Much of the Hyperscale service is resilient but the document you have filed this issue under does not include any details. The Hyperscale FAQ document does have an entry that touches upon this subject: For high availability, do I need to provision additional compute nodes

In Hyperscale databases, the resiliency is provided at the storage level. You only need one replica to provide resiliency. When the compute replica is down, a new replica is created automatically with no data loss.

However, if there’s only one replica, it may take some time to build the local cache in the new replica after failover. During the cache rebuild phase, the database fetches data directly from the page servers, resulting in degraded IOPS and query performance.

For mission-critical apps that require high availability, you should provision at least 2 compute nodes including the primary compute node (default). That way there is a hot-standby available in the case of a failover.

Please provide some clarification as to what is desired or what information is missing. Thank you!

Mike-Ubezzi-MSFT commented 5 years ago

@stevestein For awareness.

jovanpop-msft commented 4 years ago

@Mike-Ubezzi-MSFT @stevestein

I agree that these information should be here, but currently all hyper scale related info are placed on a single page HS HA is here: https://docs.microsoft.com/en-us/azure/sql-database/sql-database-service-tier-hyperscale#database-high-availability-in-hyperscale

Maybe you should contact @denzilribeiro to check what is the plan with moving info from that page to other parts of documentation.

denzilribeiro commented 4 years ago
dimitri-furman commented 4 years ago

please-close