Any way to temporarily make the node under maintenance invisible from "nodetool status" output?
I don't think so.
I would use a different approach like for example only warn/email when the node is down for 30 seconds or a minute depending on how long it takes for your nodes to restart. This way the failure is not invisible, but ignored when only bouncing the nodes.
As a side note, be aware that the 'nodetool status' only give a view of the cluster from a specific node, that can be completely wrong as well :).
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