ufw-allow

Allow traffic through Uncomplicated Firewall

TLDR

Allow all traffic on a port

$ sudo ufw allow [port]

Allow traffic for a protocol on a port

$ sudo ufw allow [port]/[protocol]

Allow a known application profile

$ sudo ufw allow OpenSSH

Allow all traffic from a source address

$ sudo ufw allow from [source_address]

Allow TCP from one host to another on port 443

$ sudo ufw allow from 192.168.1.12 to 192.168.1.100 port 443 proto tcp

Allow with a comment for documentation

$ sudo ufw allow 5432 comment "PostgreSQL"

Simulate an allow rule without applying it

$ sudo ufw --dry-run allow 80/tcp

SYNOPSIS

ufw [--dry-run] allow [rule]

ufw allow adds an allow rule to Uncomplicated Firewall so matching packets are accepted. Rules can be simple port allows (`ufw allow 22/tcp`), service or application profiles (`ufw allow OpenSSH`), or full five-tuple style rules with source, destination, port, protocol, and interface.Allow rules are typically configured before `ufw enable` on remote hosts so SSH and other admin access remain available. Use `ufw status numbered` to list rules and `ufw delete` to remove them by number.

PARAMETERS

allow

Permit matching traffic (inserts an allow rule)

port[/protocol]

Simple form: port number, optional /tcp or /udp

from address

Match source address or network (CIDR)

to address

Match destination address

port port

Destination port (or range) when using full rule syntax

proto protocol

Protocol: tcp, udp, gre, etc.

in / out

Direction of traffic

on interface

Limit rule to a network interface

comment 'text'

Attach a human-readable comment to the rule

--dry-run

Show what would change without applying it

INSTALL

sudo dnf install ufw

sudo pacman -S ufw

sudo apk add ufw

sudo zypper install ufw

CAVEATS

Requires root or sudo. Order and default policies (`ufw default deny incoming`) matter — an allow rule only helps if the default policy would otherwise block the traffic. Application profile names must match installed profiles under `/etc/ufw/applications.d/`.