= Ubuntu Uncomplicated Firewall (ufw) cookbook of configuration examples Author: Yuri Slobodyanyuk, https://www.linkedin.com/in/yurislobodyanyuk/ <> + <> + <> + <> + <> + == Disable/unload the firewall Beware: after running this command all access restrictions imposed by ufw rules will be gone. `*ufw disable*` == Verify status of the ufw firewall `*# ufw status*` - Show short status. + .... Status: active To Action From -- ------ ---- 22 ALLOW Anywhere Anywhere ALLOW 10.10.10.0/24 22 (v6) ALLOW Anywhere (v6) .... `*ufw status verbose*`- Show all rules, including the default ones, and logging level. ---- Status: active Logging: on (low) Default: deny (incoming), allow (outgoing), allow (routed) New profiles: skip To Action From -- ------ ---- 22 ALLOW IN Anywhere Anywhere ALLOW IN 10.10.10.0/24 22 (v6) ALLOW IN Anywhere (v6) ---- `*ufw status numbered*` - Show rules with their sequence numbers, that we can later use to delete some specific rule. ---- Status: active To Action From -- ------ ---- [ 1] 22 ALLOW IN Anywhere [ 2] Anywhere ALLOW IN 10.10.10.0/24 [ 3] 22 (v6) ALLOW IN Anywhere (v6) ---- == Enable ufw firewall *ufw enable* - Enable _ufw_ firewall and load the default rules, as well as user created if any in the `/etc/ufw/user.rules`. == Allow SSH access to this server from Any IP source `*ufw allow 22*` - Add port 22 to the `filter` table with action of `allow`. The rule will be added to the `/etc/ufw/user.rules` file and will survive reboot. == Delete a rule by its number `*ufw delete *` + First, see the rule numbers with `*ufw status numbered*`. Let's say I want to delete rule number 2: ---- # ufw delete 2 Deleting: allow from 10.10.10.0/24 Proceed with operation (y|n)? y Rule deleted ---- On deleting a rule, the ufw moves rules up, taking place of the removed rule in sequencing. That is, the rule that was numbered 3 before the deletion of rule 2, will become new rule number 2.