I've resolved all the critical Upgrade Assistant issues in prep for a 7.17 -> 8 upgrade, including removing 'freeze' steps from my ILM policies. But there are nearly 150 "Freezing indices is deprecated" warnings left.
My current understanding is that for each index I could use the rest api to _unfreeze, and then push a blob with a read only attribute, and then another to move the index to cold storage.
That's 450 curls... Obviously this could be done in a script, but am I missing something? Is there some 'fix it' button somewhere that I haven't noticed in Kibana? Or will that automatically happen once the cluster is brought up to v8 on all nodes?