How to determine the correct component combination in ESS WD JAVA

Please use the maintenance optimizer (MOPZ) to determine the packages which fit together:
Please check http://service.sap.com/solman-mopz for further information.

What to do if the frontend and backend EHP is not the same?
If you are not on the same EHP in frontend and backend, please keep in mind that every EHP stack is related to an ECC 6.0 stack.
The detailed connection between the stacks can be found in note 1064635.
Important is to stay in one stack (or in the same stack compared to ECC 6.0 in case you mix the EHPs)So, even if the mopz won't allow to mix EHPs, you may do this as long as you do not activate Business Functions in R/3 for EHPs which are not available in your frontend.

Which influence has the NW release?
The NW releases 7.0* are slightly different, but there shouldn't be an influence on the on the HR functionality.
An upgrade of the NW release shouldn't have an influence on the HR functionality, beside release NW 7.3.

Upgrade to  NW7.3:
On NW 7.3 the old JAVA application packages won't run. You need to use the JAVA packages for NW 7.3: ESS 633, MSS 630, PCUI_GP 633 (or upgrade to WDA). The business package for 7.30 based on Web Dynpro ABAP (WDA) is called BPERPESSWDA 1.50

ESS/MSS Business Packages. Portal 7.3 Upgrade / Migration ---------- (2)

We had the above challenge when we upgraded to 7.3 and EHP5 at the same time. I have also seen a few post on SCN on this subject so hopefully this blog can help someone in the same situation. The information below is based on my own findings so I can't guarantee its correctness - so please write a comment to the blog if you have any corrections or clarifications

Let’s get to the point! If you are upgrading to SAP NW Portal 7.3 and currently using Web Dynpro Java (WDJ) based ESS/MSS (XSS from now on), you need to consider what to do. There are different options available depending on which EHP your ECC 6.0 HR system is on (EA-HR component):

 

1. Keep using the “old” WDJ XSS services by upgrading them. If you are on EHP4 this is your only option but you can also use this approach if you are on
   EHP5 or above.
2. Use the new Web Dynpro ABAP (WDA) XSS services. This is an option from EHP5.
3. Use a combination of the old WDJ and the new WDA XSS services. This is an option from EHP5.
4. If you are on EHP3 or below your options are a bit more complex. I'll try to explain them in the bottom of this post.

  

I will now explain the 4 options above in a bit more detail.

Option 1

ESS/MSS Business Packages. Portal 7.3 Upgrade / Migration ---------- (1)

Upgrade to EHP5 and/or NW7.3:

With EHP5 SAP delivers the new WebDynpro ABAP related services. These services can be called directly in NWBC or may be called in the portal with the EHP5 Business Packages.
As these services are WebDynpro ABAP based there is no need for application packages anymore.

Be careful if you use EHP5 and still the JAVA based services:

- the EHP5 Business Packages call the WD ABAP services, so if you want to use WD JAVA you need to use EHP4 BPs, even if your backend is on EHP5.

Be careful if you use NW 7.3 and still the JAVA based services:

- on NW 7.3 the old JAVA application packages won't run. You need to use the JAVA packages for NW 7.3: ESS 633, MSS 630, PCUI_GP 633

The business package for 7.30 based on Web Dynpro ABAP (WDA) is called BPERPESSWDA 1.50.  More about switching to ESS WDA in the SAP Note 1450179 (CA-ESS-WD) ESS Based on Web Dynpro ABAP Available as of EHP5.