Rules for (G)UFW

UFW anschalten

ufw enable

UFW abschalten

ufw disable

Status überprüfen

ufw status

To                         Action      From--                         ------      ----80/tcp                     ALLOW IN    Anywhere80                         ALLOW IN    Anywhere443                        ALLOW IN    Anywhere22                         ALLOW IN    Anywhere80/tcp (v6)                ALLOW IN
Anywhere (v6)80 (v6)                    ALLOW IN    Anywhere (v6)443 (v6)                   ALLOW IN
Anywhere (v6)22 (v6)                    ALLOW IN    Anywhere (v6)443/tcp                    ALLOW OUT
Anywhere22/tcp                     ALLOW OUT   Anywhere80,443/tcp                 ALLOW OUT
Anywhere443/tcp (v6)               ALLOW OUT   Anywhere (v6)22/tcp (v6)                ALLOW OUT
Anywhere (v6)80,443/tcp (v6)            ALLOW OUT   Anywhere (v6)

Spezifische Ports

Teamviewer:

5938                       ALLOW OUT   Anywhere5938 (v6)                  ALLOW OUT   Anywhere (v6)

KDEConnect / GSConnect:

1714 bis 1764                       ALLOW OUT   Anywhere1714 bis 1764 (v6)                  ALLOW OUT   Anywhere (v6)

Neuen/Anderen SSH-Port öffnen:

ufw allow xxxx/tcp

detailed source:

https://community.teamviewer.com/t5/Knowledge-Base/Which-ports-are-used-by-TeamViewer/ta-p/4139

https://www.digitalocean.com/community/tutorials/how-to-set-up-a-firewall-with-ufw-on-ubuntu-18-04

https://linuxize.com/post/how-to-setup-a-firewall-with-ufw-on-ubuntu-18-04/

https://www.linode.com/docs/security/firewalls/configure-firewall-with-ufw/

https://help.ubuntu.com/lts/serverguide/firewall.html.de

https://www.tecmint.com/setup-ufw-firewall-on-ubuntu-and-debian/

https://www.cyberciti.biz/faq/howto-configure-setup-firewall-with-ufw-on-ubuntu-linux/

root@___:~# ufw show listening

root@___:~# grep 'DEFAULT_' /etc/default/ufw

DEFAULT_INPUT_POLICY="DROP"DEFAULT_OUTPUT_POLICY="ACCEPT"DEFAULT_FORWARD_POLICY="DROP"DEFAULT_APPLICATION_POLICY="SKIP"