I've already tired to collect all information at ones (there is about 200 luns), but during heavy load deffered functions are empty, so I'm traying to resolve me problem by calling it in pools of 20 items,
I believe what you're seeing for the next-tag value is correct...it's not something you're expected to do any processing on, just pass it back to the ONTAP system so it knows where to start for the next set of records. I have an example of using a "-iter" api with python here if you're interested.
Hope that helps.
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