iptables has been a part of linux for over 20 years now, and it’s starting to show its age. In fact, it has already been replaced by nftables as of kernel 3.13. As a consequence of this transitional period, you might run into some bumps along the road while maintaining your iptables based firewall. Here are a few examples Bailey and I discovered the other day while messing around with it on Kali.<\/p>\n
Updating iptables on Kali will do far more than you might expect. In addition to installing nftables, you’ll also get something called iptables-legacy. This wouldn’t be so big of a deal if it weren’t for the fact that updating with iptables rules in place then kicks them all into iptables-legacy (still active) and clears your regular iptables. Just to add to the potential confusion, rebooting with netfilter-persistent enabled then restores those legacy rules into your regular ruleset.<\/p>\n
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So far these behaviors have only been observed on Kali and were not found when checked for on Debian and Ubuntu. If I find them anywhere else, I’ll post an update.<\/p>\n","protected":false},"excerpt":{"rendered":"