OpenSearch Transport Auth/Auth no longer supported - still attempts handshake on 9300

I’m trying to setup an OpenSearch cluster and I’m having an issue adding in a second node. I keep getting the OpenSearchException[Transport client authentication no longer supported.] error on the master node logs and [2022-06-09T16:28:42,799][WARN ][o.o.d.HandshakingTransportAddressConnector] [ngfs-data-ctc] handshake failed for [connectToRemoteMasterNode[XXX.XXX.XXX.XXX:9300]] on the data node. Is there something specific in the config files that I should be changing? Below is what they look like currently:

# --------------------------------- Discovery ----------------------------------
# ngfs-frontend.bldc.XXX.XXX.XXX
discovery.seed_hosts: [ "ngfs-frontend.bldc.XXX.XXX.XXX", "ngfs-data.ctc.XXX.XXX.XXX" ]
cluster.initial_master_nodes: ['ngfs-frontend-bldc', 'ngfs-data-ctc']
# ---------------------------------- Various -----------------------------------
# --------------------- OpenSearch Security Configuration ----------------------
# /etc/opensearch/certificates/fullchain /etc/opensearch/certificates/privkey /etc/opensearch/certificates/root-ca-combined.pem false
# true /etc/opensearch/certificates/fullchain /etc/opensearch/certificates/privkey /etc/opensearch/certificates/root-ca.pem

I saw this article mentioning the removal of support as of 2.x but even though all hosts are on 2.0, they seem to still run into this issue.

Thanks in advance!

We got stuck in the same situation when we were trying to send query from an OS 1.3 cluster to an OS 2.0 cluster.

So what ended up being the issue for me was that the certificate subject names for the TLS transport on each node was not matching the plugins.nodes_dn information I had. Fixing that solved the issue - though it would’ve been useful if the error were to say that that was the issue.