Cloud migration: Let’s talk about it
Now a days CLOUD word is commonly used in IT and everyone is talking about it. Isn’t it? Today I am here to talk about cloud but not specific to cloud-cloud. Today’s discussion topic is pure technical prospective that things you need to consider as an SAP Administrator person to be considered prior moving/migrating your systems to hosted solution. I am using word hosted solution because when you migrate your system to any cloud service provider it becomes hosted system. It could be by 3rd parties like Microsoft Azure, GCP, HCP or Amazon
Let’s start talking about it..
Cost of migration: This is nothing to do with you as a SAP Administrator but, you need to convince your manager or infrastructure to move systems in migration. There is always an argument by infrastructure team that “We can do this on premises by deploying physical servers and using VM environment” There is multiple things to be consider when you talk to your infra team about hosting your environment. Very high-level topics are Return of investment and Administration and maintenance cost. I am not arguing that you will save money all the time, but there are possibilities at the end of the day.
Get ready yourself to answer question below to calculate total cost cost….
First thing you need to consider is your existing environment
Get very good inventory of your existing systems and make sure you have technical architecture diagram for your reference with all third-party interfaces…
For example, you can create inventory document as below
|System||Description||OS Version||DB and it’s version||CPUs/Cores||Memory||DB size||Total Disk||IP Address||Host name|
Once you have very high-level information of your systems it will be easy for you to share this information with management team or your migration service provider. Make sure you prepare architecture/landscape/Interface/Networking Diagrams
Technical topics to be consider
Do you want to perform POC (Proof of concept)?
Ask your implementation partner if they can give you some credit to migrate and test one or two systems for free for certain time to prove that you will be fine moving in to hosted solution and result will be satisfying including outage window. Why I am talking about outage window is because it is biggest challenge for any organization to keep their core business system down for longer time. By performing POC you will have an idea that how and what to do in order to migrate systems. What are the necessary steps i.e. backup restore, DB attach detach or system export import etc.
OS & DB considerations:
The question you need to ask your self is as below for OS and DB migration….
- Are we planning to upgrade OS and DBs?
- What will be our target OS and DB?
- Migrating BOBj is tricky and you need to get help with migration experts or third-party tools which are certified by SAP.
- SAP Java based systems need to be exported and imported in to target.
Note: Make sure you have exact count of server to be migrated.
Prepare your existing DR configuration details including network routes. Make sure you have mentioned RTO and RPO for your DR in the document.
How it’s been configured. i.e. SQL is clustered or AlwaysON and multiple App servers are in place. For Tomcat systems hardware load balancer in use etc.
Early Watch Alerts:
Detailed study of you SAP early watch alerts to make any adjustments at the time of migration. This is an outage window and why not take time to adjust some profile parameters or system tunings? Think about it!!!
App Access methods:
What types thick clients are in use to access your system is also more important factor deciding network connectivity from and to your site to hosting provider. For i.e. Web browser apps are very chatty and need more bandwidth. GUI/Web browser?
Ask your provider what types of connectivity and options available?
How are you going to accessing existing SAP servers in hosted solution matters to you? You do not want everyone in your network able to access your all your servers. You can have JUMP Box in hosted environment to remote in or SSH to your servers or run any other tools. This server can be accessed via internet so you can perform your server maintenance too.
Think about SAP Router placement.
Some of the older version of system are still there and you can decide you want to upgrade convert system at the same time or not? For example, Non-Unicode to Unicode?
Simple question about backup will solve your backup storing problems. Retention of backup in hosted solution is little expensive so please ask your self-question below
What current backup retention policy is? What current backup policy is? i.e. log and DB backup schedules. Make sure you also know what backup tools you have and how you want to deploy them?
Number of servers:
Have a good inventory of your virtual and physical server by environment. Number of servers to be migrated?
Have a very good idea about your used storage by environment DEV/QA/Prod/Sandbox. This will allow you to select how much disks you need to span as standard and premium. i.e. DEV and Sandbox generally do not need premium disks or it’s backups
Firewall & networking:
Prepare the list of firewall ports to be open by system so you can decide what ports to be open for public access and what are for internal access. Have very good knowledge of inter connectivity including external systems connectivity of your landscape. Decide on you need DNS server, authentication server hosted solution or not?
List any changes required in OD/DB during migration? If answer is Yes, – Make a list of what type change required. For example, SAP version upgrade during Migration?
Hope this high-level overview document helps you to migrate your systems successfully.
Comments are always welcome.