On the question related to the etcd installation in the controlplane node of the one of the cluster of the pool, I follow the official procedure described on the official etcd documentation for v3.5.0 and can’t be run since the GO version installed is too old to support that. It could be possible to get the GOP versions updated to minimum 1.16.0. and fore in order to simplify the steps and optimize time?
Here is the link referred above: Install | etcd