Unix and Linux Stack Exchange
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Questions tagged [nftables]

nftables is the successor of iptables/ip6tables and available since Linux kernel version 3.13

nftables is a facility in the Linux kernel which replaces the older iptables infrastructure and makes it somewhat easier to express rules for both IPv4 and IPv6 in parallel, where the same rule is desired.

Its CLI frontend tool is named nft.

Further reading

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Can nftables and iptables/ip6tables rules be applied at the same time? If so: what's the order of precedence?

The question is pretty much already in the title: Can nftables and iptables/ip6tables rules be applied at the same time? If so: what's the order of precedence? The reason I ask is this: plenty of tools - especially from the realm of containerization…
0xC0000022L
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nftables rule: No such file or directory error

I am trying to apply below nftables rule which I adopted from this guide: nft add rule filter INPUT tcp flags != syn counter drop somehow this is ending up with: Error: Could not process rule: No such file or directory Can anyone spot what…
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Packet processing order in nftables

I am moving from iptables to nftables. I have a basic questions about the packet processing order in nftables. Since one can create multiple tables of same type, say inet, and also chains can be created inside each table with different or the same…
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When and how to use chain priorities in nftables

When configuring a chain in nftables, one has to provide a priority value. Almost all online examples set a piority of 0; sometimes, a value of 100 gets used with certain hooks (output, postrouting). The nftables wiki has to say: The priority can…
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CentOS 8 firewalld + nftables or just nftables

I've been on CentOS 7 for a long time and was used to building my custom iptables configurations on a variety of both personal and business boxes. I've recently started working with CentOS 8 and learned of the move from iptables to nftables and so…
oucil
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How to match both UDP and TCP for given ports in one line with nftables

How can i do this in a single line? tcp dport 53 counter accept comment "accept DNS" udp dport 53 counter accept comment "accept DNS"
Microsoft Linux TM
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How to do Masquerading with NFTables

How would I implement a masquerading rule like this iptables one in NFTables: iptables -t nat -A POSTROUTING -s 10.5.6.0/24 -o eth0 -j MASQUERADE I've looked for it, but couldn't find out how to set the output interface
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nftables remove all rules in chain

I have a number of rules in table mytable chain mychain: > sudo nft -a list table mytable table ip mytable { # handle 8 chain mychain { # handle 1 type filter hook input priority filter; policy accept; tcp…
Sergey
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How to prevent iptables and nftables rules from running simultaneously?

I'm trying to set up a firewall on my own desktop (currently I'm tinkering with a Fedora 29 virtual machine). I would like to have it on the "deny-everything-by-default" basis. Almost immediately I decided to disable and mask the firewalld.service,…
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Multicast ICMPv6 comes back with conntrack state invalid

I was playing arround with the Multicast feature of IPv6. $ ping ff02::2%wlp3s0 This should normally result in an echo-reply from all the routers on your local network segment (Wikipedia - IPv6). So in my case my home router. However, I found out…
Hermilton
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nftables ip set multiple tables

Use case: I have a home router using iptables today. I'm researching converting over to nftables, as it looks to be much more manageable for a lot of rules. One thing I have setup today under iptables is a 'country-block' ipset which contains…
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What is the relationship or difference among iptables, xtables, iptables-nft, xtables-nft, nf_tables, nftables

I have been reading for a while now. What I understood is: nftables is the modern Linux kernel packet classification framework. nftables is the successor to iptables. It replaces the existing iptables, ip6tables, arptables, and ebtables…
Ahmad Ismail
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nftables map `port` to `ip:port` for DNAT

Is it possible to have an nftables map which maps port to ipv4_addr:port, where port and ipv4_addr:port have different TCP port numbers? For example, I want to dnat all incoming packets on port 80 to a container running a web server on port 8080…
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Check whether iptables or nftables are in use

Given a host that is in an unknown state of configuration, I would like to know if there is an effective way of non-interactively determining if the firewall rule set in place is managed by iptables or nftables. Sounds pretty simple and I've given…
Pedro
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What is the difference between NFTables and BPFilter?

I trying to secure my home network with OpenWRT routers. In this context I started to customize my iptables rules to my needs and found some iptables concepts hard to understand. I've discovered that nftables is the NEXT big change in firewall…
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