BPFILTER: the next-generation Linux firewall

Last updated on July 10th, 2018The Linux community has a continuous drive to enhance the GNU/Linux kernel. When we look at network traffic filtering, we moved from ipchains to iptables. More recently we saw the introduction of nftables. Next in line is BPFILTER, part of the development work for the Linux 4.18 kernel. What is BPFILTER? BPFILTER is short for BPF based packet filtering framework. In other words, it is a framework that does packet filtering and is based on BPF. […]

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Beginners Guide to nftables Traffic Filtering

Last updated on April 24th, 2017Traffic filtering with nftables Many Linux administrators became familiar with iptables and ip6tables. Less familiar are tools like arptables and ebtables. Meet the successor of them all: nftables, a packet filtering framework, with the goal to replace all the previous ones. After reading this guide you will be able to configure your own firewall configuration. Step by step we will show how nftables work. Although no knowledge of iptables is needed, we will share some […]

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Differences Between iptables and nftables Explained

Last updated on October 10th, 2016iptables VS nftables The seasoned Linux administrator will be familiar with iptables, the network traffic filter. If you ever configured a Linux system with an ethernet bridge configuration, you might even have worked with ebtables. Or possibly you wanted to filter ARP traffic and used arptables? Newcomer nftables has arrived, with the purpose to replace iptables, ip6tables, ebtables and arptables. As with every big upcoming change, it is good to know the differences. We explain […]

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Block IP addresses in Linux with iptables

Last updated on December 16th, 2017Blocking IP addresses and subnets with ipset Most system administrators will already be familiar with iptables. It is around for quite a while and is enabled by default within the Linux kernel. We can use iptables to block one, multiple IP addresses, or even full networks. This may come in handy when you get repeating port scans or see failed login attempts in your log files. Time to get started and block some IP addresses! Check existing iptables configuration […]

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Exporting nftables rules and configuration

Last updated on November 23rd, 2016Exporting nftables rules The usage of nftables will slowly grow in the upcoming years, with the goal to become the successor of iptables. Where iptables rules are harder to parse, nftables comes by default with an exporting facility. Exports formats include JSON and XML. Command syntax When using the command line utility nft for the first time, it looks a little bit unfriendly to the user. No suggestions on what to do, nor clear help […]

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