After the upgrade of ARS and Midtier to version 20.02, there is issue on console related to:
..................
ARERR [8790] java.lang.NoClassDefFoundError.
..................

Steps to Reproduce:
1. Upgrade Midtier and AR Server from 18.08 to 20.02 release.
2. Login to the Midtier .
3. Check the SHR:LandingConsole page which comes after we login

ACTUAL RESULTS: Error while accessing console and forms.
..................
ERROR (8790): Unknown system error; java.lang.NoClassDefFoundError: org/bouncycastle/jcajce/provider/asymmetric/rsa/BCRSAPublicKey
Unknown system error :
java.lang.NoClassDefFoundError: com/bmc/arsys/serveradmin/impl/ServerInfoVendorTable$1 (ARERR 8790)
..................

If AR service is restarted everything works well, again after one day or after sometime java.lang.NoClassDefFound Error starts appearing again.
The issue is not seen in environment with fresh install of ARS 2002, but only with upgraded ones.
Impacted modules are: DWP, SRM, SMART IT, ARS, Midtier.

Below are few of the Use cases :

1. SHR:Landing Console not loaded:
.........
ARERR [8790]
Unknown system error : java.lang.NoClassDefFoundError: org/springframework/transaction/aspectj/AbstractTransactionAspect$Rethrower
.........

2. Accessing Server Information page:
.........
Unknown system error : java.lang.NoClassDefFoundError: com/bmc/arsys/serveradmin/impl/ServerInfoVendorTable$1 (ARERR 8790)
.........

3. Access Manage User Licenses:
.........
Unknown system error:java.lang.NoClassDefFoundError: com/bmc/arsys/serveradmin/impl/UserLicenseInfo (ARERR 8790)
.........

4. Saving Workorder or Change:
.........
Unknown system error :java.lang.NoClassDefFoundError: org/eclipse/persistence/expressions/ExpressionMath (ARERR 8790)
.........

5. Other different actions in Midtier:
.........
ARERR [8790] Unknown system error : java.lang.NoClassDefFoundError: com/bmc/arsys/mapping/domain/binding/rpc/RpcHandConverter$1
.........

6. While Accessing ARInput step in Spoon Client:
.........
ERROR (8790): Unknown system error; java.lang.NullPointerException
.........

7. While creating new Work Order through SRM console.
.........
ERROR (8790): Unknown system error; java.lang.NullPointerException
.........
Error Snippet:
.....................
<LEVEL: SEVERE > <Class: com.remedy.arsys.goat.GoatException><Method: <init>><TENANT: null > <USER: ceizelm >
ERROR (8790): Unknown system error; java.lang.NoClassDefFoundError: com/bmc/arsys/mapping/domain/binding/rpc/RpcHandConverter$1
at com.bmc.arsys.apitransport.ApiProxyJRpcBase.arCall(ApiProxyJRpcBase.java:300)
at com.bmc.arsys.apitransport.ApiProxyJRpcBase.arCall(ApiProxyJRpcBase.java:172) at com.bmc.arsys.api.ProxyJRpc.ARGetMultipleFields(ProxyJRpc.java:742)
at com.bmc.arsys.api.ProxyJRpc.ARGetListFieldObjects(ProxyJRpc.java:730) at com.bmc.arsys.api.ARServerUser.getListFieldObjects(ARServerUser.java:3510)
at com.remedy.arsys.goat.service.FormFieldService.getFieldsAsAdmin(FormFieldService.java:111)
at com.remedy.arsys.goat.CachedFieldMapInternal.getFieldsAsAdmin_aroundBody4(CachedFieldMapInternal.java:147)
at com.remedy.arsys.goat.CachedFieldMapInternal$AjcClosure5.run(CachedFieldMapInternal.java:1)
etc....
.....................
 

This knowledge article may contain information that does not apply to version 21.05 or later which runs in a container environment. Please refer to Article Number 000385088 for more information about troubleshooting BMC products in containers.

The behavior is a defect:
............
SW00566967 - After upgrading to 20.02 release, java.lang.NoClassDefFoundError error reported randomly in different workflows. 
............

A Hot Fix is available for v.20.02 and can download from here:
ftp://ftp.bmc.com/pub/ARRecommendedFixes/Server/20.02/


The fix is backported in patch 001 hotfix of v1902. Apply the AR hotfix SR_1902P1_20210507_CU_ALL to fix the issue in 1902 patch 001.

Defect details:
DRSMX-58809  - After applying the HF 9.1.07.001 202101131040 there is a null pointer exception when trying to change the password.