This could be one of my shortest article & this was due from a long time. When an organization try to migrate anything into cloud it definitely makes sense to reevaluate whether it is right to refactor, revise, rebuild or repurchase. The same questions arises when you take your databases in cloud. Today we will talk about Microsoft’s SQL Server. What makes more sense whether to repurchase with RDS or rehost using an EC2 instance. I hope by end of this article you should have an fair idea which one to choose & what things to consider before you make decision. This analysis is more from the cost evaluation perspective with some technical pointers to be considered.
Let us understand the licensing Model and what type of licenses Microsoft offers & purpose for the same.
| SQL Server edition | Definition |
|---|---|
| Enterprise | The premium offering, SQL Server Enterprise edition delivers comprehensive high-end datacenter capabilities with blazing-fast performance, unlimited virtualization1, and end-to-end business intelligence – enabling high service levels for mission-critical workloads and end-user access to data insights. |
| Standard | SQL Server Standard edition delivers basic data management and business intelligence database for departments and small organizations to run their applications and supports common development tools for on-premises and cloud – enabling effective database management with minimal IT resources. |
| Web | SQL Server Web edition is a low total-cost-of-ownership option for Web hosters and Web VAPs to provide scalability, affordability, and manageability capabilities for small to large-scale Web properties. |
| Developer | SQL Server Developer edition lets developers build any kind of application on top of SQL Server. It includes all the functionality of Enterprise edition, but is licensed for use as a development and test system, not as a production server. SQL Server Developer is an ideal choice for people who build and test applications. |
| Express editions | Express edition is the entry-level, free database and is ideal for learning and building desktop and small server data-driven applications. It is the best choice for independent software vendors, developers, and hobbyists building client applications. If you need more advanced database features, SQL Server Express can be seamlessly upgraded to other higher end versions of SQL Server. SQL Server Express LocalDB is a lightweight version of Express that has all of its programmability features, runs in user mode and has a fast, zero-configuration installation and a short list of prerequisites. |
Initial License Cost
This is one time cost you pay when you are purchasing the license from Microsoft on premises. This cost is per core & cost is somewhat same from SQL 2012 to 2019 version,so this is how you can read the below table.
The First column represents the MS-SQL Edition type & second column represents the price per core. CAL stands for Client Access License, which is perfect for small businesses because you know number of clients.
For this study first five models are useful.
On-Premises/EC2
When you decide to go with On-premises MS-SQL you need to pay the upfront cost for on premises license setup. This cost plays a major role in your decision making since it is part of huge cost for enterprise edition & Standard edition also.
In AWS RDS
So when you decide to go in AWS cloud you will not have any upfront cost and you will be paying per hour cost & you won’t be able to take your on-premises license into RDS instance.
Disaster Recovery
Disaster recovery is important coverage from most of the organization’s perspective & Microsoft very well consider this as a part of package for enterprises.
On-Premises/EC2
- Failover servers for high availability – Allows customers to install and run passive SQL Server instances in a separate operating system environment (OSE) or server for high availability on-premises in anticipation of a failover event.
- Failover servers for disaster recovery – Allows customers to install and run passive SQL Server instances in a separate OSE or server on-premises for disaster recovery in anticipation of a failover event
In AWS RDS
When you choose AWS RDS multi-AZ your per hour cost goes high.
Development/Test Environment
Microsoft offers a free developer edition for lower environment.
On-Premises/EC2
This is included in your enterprise license.
In AWS RDS
You again pay hourly, mostly in lower environment you will be using standard edition.This cost again need to be considred since in on premises this is included in your lower environment.
Read Only or Reporting Instances
On-Premises/EC2
This is included in your enterprise license & you can have as many read only instances as you want these you can use it for reporting purposes also.
In AWS RDS
You again pay hourly, mostly in lower environment you will be using standard edition.This cost again need to be considered since in on premises this is included in your lower environment.
Software Assurance/Support Package
This is another important cost which most of the enterprises need to bear. The defination around this package is vague but it is essential and as an organization I hardly believe why one should not purchase it.
On-Premises/EC2
This cost is not fixed & it comes close to 25% of your original license, this covers you from below things
- Reduce software and services costs with rights to new software releases and cost-efficient upgrades.
- Use consulting services to plan new, on-premises deployments.
- Improve operational efficiency through access to unique technologies and licensing rights.
- Increase overall user productivity with instructor-led technical training.
- Maintain an available and responsive IT infrastructure with as-needed support.
In RDS
This cost is covered in your hourly usage charges. I assume you will get similar type of support.
SSRS -Reporting Module Access
On-Premises/EC2
On premises MS-SQL server has direct access to all the modules related SQL Server Reporting Services.
In RDS
Till June 2020 AWS RDS did not use to give access to SQL Server Reporting Services but for MS SQL 2017 onwards you can have it on the same server.
Starting today, Amazon RDS for SQL Server supports SQL Server Reporting Services (SSRS), giving you the ability to host the report server web portal on the same Amazon RDS DB instance as your SQL Server database. There is no additional cost to install SSRS directly on your Amazon RDS DB instance.
Human Effort
This is no brainer but as you know if you move onto EC2, it becomes your responsibility of maintaining & keeping it on all the time. This is not the case when you move on to RDS.
Conclusion:
These are some of the points, I will suggest to consider when you go in AWS with SQL Server. If you are planning on sticking with SQL Server for a longer duration then don’t fall into Sunk Cost fallacy paradigm, it is one time repurchase cost but I see major benefit in long term perspective.
Sachin Kapale 