I have an Azure Storage account with 2TB of data. For the design of a disaster recovery solution how I can recover it on a remote site with huge data?
Azure Storage has different data redundancy modes to provide recovery in case of a disaster.
Locally redundant storage (LRS) copies your data synchronously three
times within a single physical location in the primary region. LRS is
the least expensive replication option, but is not recommended for
applications requiring high availability or durability.
Zone-redundant storage (ZRS) copies your data synchronously across
three Azure availability zones in the primary region. For applications
requiring high availability, Microsoft recommends using ZRS in the
primary region, and also replicating to a secondary region.
Geo-redundant storage (GRS) copies your data synchronously three times
within a single physical location in the primary region using LRS. It
then copies your data asynchronously to a single physical location in
the secondary region. Within the secondary region, your data is copied
synchronously three times using LRS.
Geo-zone-redundant storage (GZRS) copies your data synchronously
across three Azure availability zones in the primary region using ZRS.
It then copies your data asynchronously to a single physical location
in the secondary region. Within the secondary region, your data is
copied synchronously three times using LRS.
Related
I want to implement a multi-region architecture in azure. My current architecture is running in one region and I am using blob storage to save my data. I was wondering if the blob storage can be shared between users in different regions? because I have seen that the replication is read-only otherwise I have to create another blob storage for the other regions ? and how I synchronize it to have the same data so the users in different regions can see the same content in the software?
I was wondering if the blob storage can be shared between users in
different regions?
Blob storage can certainly be shared between users in different regions. Blob storage resources are accessible over HTTP protocol so it doesn't really matter where your users are.
However please note that you may incur extra charges for data egress if the blob storage data is consumed by the application in your secondary regions.
Furthermore, you will notice some increased latency for both reads and writes. You can reduce the read latency by fronting your blob storage with CDN (but then you will pay extra for the CDN).
There is little documentation on how ASTRA DB stores data. So, i could not do much research on this. I wanted to know which of the storage options do ASTRA DB use to store data in azure blob. The storage options are
LRS(Locally Redundant Storage) - copies data synchronously three times within a single physical location in the primary region
ZRS(Zone-redundancy storage) - Copies data synchronously across three Azure availability zones in the primary region
GRS(Geo-redundant storage) - Intermediate option with failover capabilities in a secondary region
GZRS(Geo-zone-redundant storage) - Optimal data protection that includes both GRS and ZRS.
Thanks
Serverless databases are automatically replicated across three availability zones - see About your Astra DB database.
Each Astra DB database uses replication across three availability
zones within the launched region to promote uptime and ensure data
integrity.
This would mean ZRS in the case of Azure.
Using RA-GRS Azure Storage Account, is it possible to write to a blob path in both regions?
We have two regions running the same data flows active-active (configured via Traffic Manager), however one legacy application used for file transfer to our on premise estate will only be available in the primary region. In case of DR we will manually stand up the application in the secondary region. (This is due to a limitation in the application itself.)
So the storage needs to be written to in both regions, but only in the primary region we will read (and delete on success) the data. Does RA-GRS allow this? Some delay in the files being synced to primary region will not be a problem.
Azure Storage Account RA-GRS does not offer two-way synchronization, you would need to implement a solution yourself. azcopy offers some functionality for doing this.
Why do we need Azure backup for our VMs (disks) on azure, when azure storage account provides different replication options like LRS, ZRS, GRS, RA-GRS.
All the data is already replicate in different region (in case of GRS), what advantes I will get out of Azure Backup.
All the data is already replicate in different region (in case of
GRS), what advantes I will get out of Azure Backup.
Replication is not backup!
It is true that when you opt for GRS replication, 6 copies of your data is maintained (3 in primary and 3 in secondary) but when you delete the data from primary, data from secondary is automatically deleted.
UPDATE
You mean, if any data is deleted/corrupted due to some error/bug, can
be reproduced from backup and it is not possible in case of storage
replication.
You're absolutely correct!
But Microsoft sells "Azure backup and Site recovery" as a BCDR
strategy. In context of any disaster, why not just rely on Storage
replication. Any advantages of Azure backup/site recovery?
I have not used Azure backup so let me answer it from Storage Replication point of view. To put things simply, "In context of Azure, a disaster is not a disaster unless Microsoft thinks it is a disaster". Till the time that happens, you don't get access to secondary assuming you have opted for GRS replication (with RA-GRS, you obviously have an option to read the data from secondary at all times).
Furthermore if you choose LRS or Premium LRS replication and there's indeed a disaster in one data center, all of your data will be lost. With Azure Backup, you at least have a copy of your data lying somewhere safe and you could recreate your environment based on that backup.
I know this question is old but MS provide a solution for Disaster recovery by Storage account
We may have 2 solution for dealing with Disaster
https://learn.microsoft.com/en-us/azure/storage/common/storage-disaster-recovery-guidance?toc=/azure/storage/blobs/toc.json
it said :
If the primary endpoint becomes unavailable for any reason, the client is no longer able to write to the storage account. The following image shows the scenario where the primary has become unavailable, but no recovery has happened yet:
enter image description here
The customer initiates the account failover to the secondary endpoint. The failover process updates the DNS entry provided by Azure Storage so that the secondary endpoint becomes the new primary endpoint for your storage account, as shown in the following image:
enter image description here
I am using Azure Table Storage. I am using RA-GRS replication model. I would like to know what happens in the case of a failure to the primary region, will I be able to write to a secondary region?
Secondaries are read-only, by design. If there's a catastrophic situation within a region, your secondary storage account could be shifted to primary, but 1) that's outside your control and 2) a very rare exception (e.g. never happened before, as far as I know).
If you absolutely need to maintain ability to write, then it would be up to you to have an alternative storage account with primary region being different from your main storage account's region.