Once upon a time, Jonathan Billings billings@negate.org said:
'iptables' and 'nftables' are competing technologies. In CentOS 8, firewalld's backend was switched from iptables to nftables. So it would be expected that the iptables command wouldn't have any rules defined, it isn't being used by firewalld.
That is partially incorrect. While iptables and nftables are two different in-kernel firewalls, the iptables CLI command is now a wrapper that can translate to the nftables backend for compatibility.
However, it can only manage a subset of nftables information (basically what it can create in the iptables back-compat mode). The nftables rules created by firewalld don't fall into that category, so can't be viewed by iptables.
Instead, use the nft command, like "nft list ruleset" to see a dump of all current rules.