Provide disaster recovery by replicating storage data across regions and failing over to a secondary location

Question 1

Locally redundant storage

Answer 1

Locally redundant storage (LRS) copies your data three times across separate racks of hardware in a datacenter, inside one region. Even if there’s a hardware failure, or if maintenance work is happening in the datacenter, this replication type ensures data is available for use.

Question 2

Limitation of local redundancy storage

Answer 2

LRS doesn’t protect you from a datacenter-wide outage. If the datacenter goes down, you could lose your data.

Question 3

Geographically redundant storage

Answer 3

With geographically redundant storage (GRS), your data is copied three times within one region, and three times in a secondary region that’s paired with it. This way, if your primary region is experiencing an outage, your secondary region is available for use.

Question 4

Read-access geo-redundant storage

Answer 4

With GRS, your secondary region isn’t available for read access until the primary region fails. If you want to read from the secondary region, even if the primary region hasn’t failed, use RA-GRS for your replication type.

Question 5

Zone-redundant storage

Answer 5

Zone-redundant storage (ZRS) copies your data in three storage clusters in a single region. Each cluster is in a different physical location and is considered as a single availability zone. Each cluster uses its own separate utilities for things like networking and power. If one datacenter is experiencing outage, your data remains accessible from another availability zone in the same Azure region.

Question 6

Limitation of Zone-redundant storage

Answer 6

Because all availability zones are in a single region, ZRS can’t protect your data from a regional level outage.

Question 7

Read-access geo-zone-redundant storage

Answer 7

Read-access geo-zone-redundant storage (RA-GZRS) uses the same replication method as GZRS but lets you read from the secondary region. If you want to read the data that’s replicated to the secondary region, even if your primary isn’t experiencing downtime, use RA-GZRS for your replication type.

Question 8

Paired regions

Answer 8

A paired region is where an Azure region is paired with another in the same geographical location to protect against regional outages. Paired regions are used with GRS and GZRS replication types.

Question 9

Switch replication strategies

Answer 9

ou can switch your replication strategy for any storage account. The process you use depends on the current replication strategy for your account

Question 10

Convert account

Answer 10

f you’re using a ZRS account, you can convert it to use GZRS. You convert an account using the Azure portal, the Azure CLI, or Azure PowerShell.

Question 11

Azure PowerShell to convert

Answer 11

Set-AzStorageAccount -ResourceGroupName -AccountName -SkuName “Standard_GZRS”

Question 12

Live migration

Answer 12

You can also use live migration to migrate your data to an account that uses ZRS, GZRS, or RA-GZRS. Use live migration to avoid downtime or data loss. The duration of your live migration generally depends on the amount of data in your account.

Question 13

There are some limitations to live migration

Answer 13

Unlike a manual app, you won’t know exactly when a live migration will complete.
Data can only be migrated to the same region.
Live migration is only supported for data held in standard storage account types.
If your account contains a large file share, live migration to GZRS isn’t supported.

Question 14

Manual migration

Answer 14

Manual migration is more flexible than live migration. For example, because you control the timing, you can use manual migration if you need completion by a fixed date.

Question 15

How the failover process works

Answer 15

Azure Storage lets you fail over your storage account to a different region if the primary region becomes unavailable. When a failover is triggered and completed, your data is accessible from a secondary region. You use the secondary region until the primary region is up again.

Question 16

Data loss

Answer 16

When you fail over your account, you’ll have some data loss. This loss happens because your data is copied asynchronously. When data is copied in this way, there’s always a delay before it’s copied from the primary region and written to the secondary. It might be that your most recent writes haven’t been copied to your secondary region yet, before your primary failed.

Question 17

Data loss 1

Answer 17

Also, when you start a failover, data in your primary region is lost. Any data that wasn’t written to the secondary before you started the failover is also lost.

Question 18

Track Azure Storage service outage

Answer 18

We recommend you track the health status of Azure Storage and other Azure services by using Azure Service Health. You can subscribe to these updates with your applications and configure applications to handle or report issues to you.