Once again it was related to hostname configuration (I remember had problem with this multiple times before even on different applications), this time the root cause was a typo in one of multiple config files for hostname (different name on /etc/hostname with /etc/hosts)! I fixed that and now there is no problem.
I wonder how Cassandra-3.11 worked?! P.S: Default dc name in version 4 was changed to datacenter1 (from dc1) and it seems to cause a bit of problem with previous configs(default one in rack-dc conf still is dc1). Thank you Best Regards Sent using https://www.zoho.com/mail/ ============ Forwarded message ============ From: Erick Ramirez <erick.rami...@datastax.com> To: <user@cassandra.apache.org> Date: Mon, 31 Jan 2022 15:06:21 +0330 Subject: Re: Problem on setup Cassandra v4.0.1 cluster ============ Forwarded message ============ TP stats indicate pending gossip. Check that the times are synchronised on both nodes (use NTP) since it can prevent gossip from working. I'd also suggest looking at the logs on both nodes to see what other WARN and ERROR messages are being reported. Cheers!