Here is what I would do :
First I will do and record all the steps in the Console needed to perform the changes - that would (high level with out knowing your implementation) be something like :
- Identify the old user to be deleted
- For each account - transfer account to new user
- Delete old user
I would then look if something could go wrong in that process (when you transfer an account it should be updated according to policies applying for the new user). I would then look into how I would want to implement it (custom UI, workflow or external e.g. SDI) to size the effort and also evaluate if this SHOULD be implemented or just handled as a manual process. This means looking into what APIs could be used and how to call them etc.
In general my advice is not to implement this as a process - it is not something simple to do unless you have a lot of experience in coding with ISIM internal APIs and there could be a lot problems. Normally the rule should be that a new Identity should NOT inherit another (old) Identities accounts as this may be a security issue on top of the technical challenges...
HTH
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Franz Wolfhagen
WW IAM Consulting Leader - Certified Consulting IT Specialist
IBM Security Expert Labs
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