Should the Central Instance be separated from the DB Server?

[Former Member]

I am planning for a distributed ECC system. I plan to have multiple Dialog Instances. I am trying to determine whether or not I want to install the Central Instance on the same system as the Database. I am using a virtualized environment, so I am not concerned with the network between the two systems. I have been told by my VAR that it is recommended to separate the DB server and the CI but I don't see why. Knowing that the CI talks directly to the DB, why wouldn't you want to keep them together? I am adding this post to find out what others are doing and what they recommend.

[Former Member · Accepted solution]

Will your VM's be spread across multiple systems? If you are running these across just one or two systems then it may not make sense to split the CI from the DB since you are not distributing the load. Of course, when you do split these it does give you the chance to scale across multiple VM host systems in the future.

[Former Member · Accepted solution]

They will be spread across two physical systems.

We have made the decision to create the Central System. We actually ran into some issues with our BSI application. It was not able to calculate taxes correctly in the Distributed system. Also, we feel we have ample CPU and memory and combining the two systems should not cause any hardware bottlenecks. We also chose this design in order to free up more hardware resources for Dialog Instances. With the added Dialog instances, we can prevent users from logging on directly to the Central Instance.

[Former Member · Accepted solution]

That sounds like a good plan. I have seen that done before where users are directed toward dialog servers and the CI is setup only for admin access and background processing.

[Former Member]

Hi Bob,

When doing distribuited ECC installation the idea is that you will install DB and CI in differents Hardware Boxes, if you want to install CI and DB in one box then the installation should be as Central System because everything will go in one Box.

Now the question here is what you need?

Usually distribuited installations is done for productive systems because in this way Database instance will not share Hardware resources with other instances so you could give more RAM memory (an example) for the DB management system and CPU will be only used by SQL Server, also HDD will only work for the RDBMS, this will improve performance of course. In the CI Instance you will have also all CPU and RAM memory for SAP ABAP or Java work so while not sharing resources you could, for example, increase Dialog WP's, use more memory for extended memory, etc.

Another use for distribuited installations is if in contrary you have two boxes with low resources so you can install CI and DB together because if not, performance will be unaceptable.

So if you have enought HW resources and this will be more than enough, and/or performance is not a top priority, or this will be a test, training, DEV or QAS system or low use PRD system then you could just need to use a Central Installation.

In your case as you are using virtualization then you could add enough HW resources to one virtual machine and do a central installation, it is more straigth forward and for some system maintenances and configurations this one needs less effort. Your Disks will be on a SAN or similar so this won´t affect performance.

In my opinion you don´t need distribuited installation.

Good Luck