Mirroring Service and Azure

Hi all.

I'm about to begin on setting up Mirroring for a rather large customer, who wishes to use Azure to host the service and database. I have found a few forum posts touching the subject, but not something that specifically answers the questions that came up during a recent meeting i had with the customer, so here i am asking. :)

So, i can read that there should not be any problems in deploying a mirror database in azure, but the customer asks whether i would advise them to use a normal Azure SQL Database og a Azure SQL MI (Managed Instance) Database. In my view, a standalone database would be preferred, as they are going to have a production environment, as well as two test environments mirrored - and the production environment will most likely require much more computing power than both of the test environments, as the production environment will be queried more often. But in terms of functionality or maybe lack thereof compared to on-premises, i don't think it seems to be missing anything. But what do you say, do you have any experience with deploying mirroring in Azure?

Thanks in advance :)

RE: Mirroring Service and Azure

HI Dennis,

While I do not have personal experience or knowledge of anyone using Database Mirroring towards a database in Azure, I don't see any reason why it should not work - as long as the target database is a MS SQL Server Database instance, which utilizes a Log Sequence Number - a requirement.

Best regards!

By: Tony Yates 25 May 2021

RE: Mirroring Service and Azure

The only experience I have to offer on Mirroring and Azure, is that it could become expensive. I tried setting up Mirroring for our production database to an Azure instance where we had $100 worth of bonus data. That got used up in about two days. I assume the initial loading of data took most of the cost, but it's something to keep in the back of your mind.

By: Frode Lillerud 25 May 2021

RE: Mirroring Service and Azure

Hi

We are running our Database Mirroring in Azure without any trouble. Using a standard App Service in combination with Azure SQL database. Our App Service code is based on the Database Mirroring example code from SuperOffice. 

I'm not sure about the running cost of this, but remember that the App Service needs to have minimum Basic (B1) App Service Plan.

 

Arild

 

By: Arild Eik 25 May 2021

RE: Mirroring Service and Azure

Frode makes a GREAT point. Do not forget about cost here... It could be far less expensive to maintain a local SQL Server installation in this case.

By: Tony Yates 25 May 2021

RE: Mirroring Service and Azure

Thanks for the suggestions, the customer is well aware about the cost, but they have just agreed to go Online, so they would like to eliminate any local servers, and they are well aware of the cost of that.

 

However, since you can't control the frequency of the updates pushed by the mirror database, a wish would be to maybe include an option in the operations center, where we can tweak the minimum time between each update of the mirror - so that for systems that do not require constant updates (Maybe just once a day for example) could be set like that - cause for customers who do choose to put their mirror in Azure, that little tweak alone could end up saving them quite an amount of money in transaction costs, that are not necessary anyway - and currently it can be a little hard to estimate any cost for cloud storage transactions, as the mirror updates can happen randomly at SuperOffice' own unknown schedule :)

By: Dennis Mortensgaard 27 May 2021

RE: Mirroring Service and Azure

I will log this wish, but just want to comment on "SuperOffice' randomly unknown schedule".

The sync is set up to start every 20 minutes, but will be delayed if there is another customer task running on the tenant that did not yet complete.

There is a pause on all mirroring tasks between 22.00 and 07:00 CE(S)T

By: Margrethe Romnes 27 May 2021

RE: Mirroring Service and Azure

Good to know Margrethe, i was of the impression that the schedule was dynamic according to the amount of changes in the database :)

 

Thanks for logging the wish though, that is still relevant for people that does not rely on updates every 20 minutes.

By: Dennis Mortensgaard 27 May 2021