An outage will be required for any method you use to migrate. Since you are already on external storage the best solution is to replicate the volumes to the new storage, including the load source. When everything is in sync, power down the LPAR, change the HMC profile to point to new load source and IPL. No need to do a load source migration in DST. There is additional work required for zoning and host mapping for the new storage.
I use the load source migration when moving customer from internal to external storage and have been told then same thing. The process is documented but not supported because of the risk of customers losing data.
From: Mitchell, Dana via MIDRANGE-L<mailto:midrange-l@xxxxxxxxxxxxxxxxxx>
Sent: Friday, November 8, 2019 11:46 AM
To: Midrange Systems Technical Discussion<mailto:midrange-l@xxxxxxxxxxxxxxxxxx>
Cc: Mitchell, Dana<mailto:dmitche@xxxxxxxxxx>
Subject: IBM supported doc
We have to move several LPAR's external storage LUNs to a different storage subsystem. It seems fairly straightforward to move most of them, I was hoping to be able to move the load source LUNs somehow without taking an outage too (using mirroring or something ?), I thought perhaps some recent developments might make that possible. After Googling I found a Redbook from 2009 that addressed IBMi and external storage, and a few hits in Knowledge Center about moving the loadsource using DST. So I opened a case with IBM to ask.
The first response I got was: 'The recommended support process is to do a clean installation on the new disk configuration.'
Me: Isn't this process IBM supported?: https://apc01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.ibm.com%2Fsupport%2Fknowledgecenter%2Fen%2Fssw_ibm_i_74%2Frzaly%2Frzalylsnprot.htm&data=02%7C01%7C%7C2dd3ef2c57694e8671fb08d7646b29a3%7C84df9e7fe9f640afb435aaaaaaaaaaaa%7C1%7C0%7C637088283730044886&sdata=W0liAUZ9uyll0TAEaDBAT3yohrcDUAVMH%2FR0byGTEfU%3D&reserved=0
IBM: 'No, it was provided by the lab as a testing example. We are working to clarify the documentation to make the distinction between lab documentation and supported processes more readily apparent to readers'.
Me: So articles in the 'Information Center' isn't all IBM supported???
IBM: I believe that is correct.
Does that bother anyone but me?
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