Why does iptables/netfilter randomly seem to not accept packets?
Issue
- When using iptables, the front-end to the netfilter module, it appears as if a random packet is seen in a packet capture but it never makes it to the application.
- When viewing this in a packet capture, sometimes an ICMP "Host Prohibited" packet is seen immediately after.
- iptables receiving and rejecting INVALID packets
Environment
- Red Hat Enterprise Linux
- iptables firewall with connection tracking (including firewalld)
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