Side by Side SQL Installation

Question

Side by Side SQL Installation

Vijay Kumar 2,036

Hi Team,

I am planning to install SQL Server 2019 on same box where already SQL Server 2016 is running.

In this is what is the best practice?

Accepted answer

3 additional answers

Your answer

Answer 1

m 4,276

Hi @Vijay Kumar ,

...In this is what is the best practice?

You can do this. However, this is not the best.

If you have more servers, I recommend you install it in one different server.

Becasue there are two principles to configure SQL Server memory:

(1) The Windows system and other key application services must have enough memory to prevent them from grabbing the memory that SQL Server has applied for due to insufficient memory during operation.

(2) Under the premise of meeting the first point, SQL Server uses as much memory as possible and must ensure the stability of the amount of memory used.

So it is best to make the server dedicated to the database, and do not install other services (such as IIS, middle-tier application services, etc.) on the same machine. Multiple production services running on the same machine will greatly increase maintenance costs.

More information: work-with-multiple-versions-and-instances-of-sql-server

BR,
Mia

If the answer is helpful, please click "Accept Answer" and upvote it.

Erland Sommarskog 121.7K Reputation points MVP Volunteer Moderator

2020-10-19T21:09:57.057+00:00

Mia, there are a whole lot of "it depends" here.. Sure, if you have two business-critical tier-1 applications, but it would be a folly to put them on two instances on the same servers in most cases.

But there are also machines that runs a number of lesser systems in the same instance. It may be desirable to have them in the same instance, but there could be security considerations that calls for having them separated. Or it can be that different applications needs different versions of SQL Server due to vendor requirements.

And we should not forget test and development servers where you need different instances to be able to support multiple SQL Server versions.

On my machine at home, I have seven instances of SQL Server running, and this is not an issue. None of them have a real workload, they all run different versions of SQL Server.
m 4,276 Reputation points

2020-10-21T01:32:47.63+00:00

Hi @Erland Sommarskog ,

Thanks for your contribution.

..."On my machine at home, I have seven instances of SQL Server running, and this is not an issue. None of them have a real workload, they all run different versions of SQL Server."

I know this situation, I have about 12 instances on my side. However they are just for testing, there are not much more workload, this is not suitble for one product environment.And most of the users are from production side, I think.

BR,
Mia

If the answer is helpful, please click "Accept Answer" and upvote it.

Answer 2

Erland Sommarskog 121.7K MVP Volunteer Moderator

It does not have to be a bad practice to have multiple instances on the same computer, and there are no particular precautions if the instances are off different versions.

The only thing to keep in mind the instances may compete for resources, and it may be a good idea to set "max server memory" so that the total adds up to, say, 90 % of the RAM in the machine.

Answer 3

Fully agree with Erland here. It is really not a bad practice. MS fully supports such scenario and has documented it work-with-multiple-versions-and-instances-of-sql-server. If you see the document it is mentioned that it is supported so it cannot be bad practice.

Existing instance	                 Side by side support  
SQL Server 2019	      SQL Server 2008 through SQL Server 2017  
SQL Server 2017	      SQL Server 2008 through SQL Server 2016  
SQL Server 2016	      SQL Server 2008 through SQL Server 2014

Answer 4

m 4,276

Hi @Vijay Kumar ,

Is the reply helpful?

BR,
Mia

If the answer is helpful, please click "Accept Answer" and upvote it.

Share via

Side by Side SQL Installation

3 additional answers

Your answer