Update cheatsheets

linux/nft

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+---
+syntax: markdown
+tags: [tldr, linux]
+source: https://github.com/tldr-pages/tldr.git
+---
+# nft
+
+> Allows configuration of tables, chains and rules provided by the Linux kernel firewall.
+> Nftables replaces iptables.
+> More information: <https://wiki.nftables.org/wiki-nftables/index.php/Main_Page>.
+
+- View current configuration:
+
+`sudo nft list ruleset`
+
+- Add a new table with family "inet" and table "filter":
+
+`sudo nft add table {{inet}} {{filter}}`
+
+- Add a new chain to accept all inbound traffic:
+
+`sudo nft add chain {{inet}} {{filter}} {{input}} \{ type {{filter}} hook {{input}} priority {{0}} \; policy {{accept}} \}`
+
+- Add a new rule to accept several TCP ports:
+
+`sudo nft add rule {{inet}} {{filter}} {{input}} {{tcp}} {{dport \{ telnet, ssh, http, https \} accept}}`
+
+- Add a NAT rule to translate all traffic from the `192.168.0.0/24` subnet to the host's public IP:
+
+`sudo nft add rule {{nat}} {{postrouting}} ip saddr {{192.168.0.0/24}} {{masquerade}}`
+
+- Show rule handles:
+
+`sudo nft --handle --numeric list chain {{family}} {{table}} {{chain}}`
+
+- Delete a rule:
+
+`sudo nft delete rule {{inet}} {{filter}} {{input}} handle {{3}}`
+
+- Save current configuration:
+
+`sudo nft list ruleset > {{/etc/nftables.conf}}`