A few days ago I installed Apache on my Ubuntu operating system.
I wanted to make the server public.
Somehow I messed up the settings of the automatic internet connection at start-up.
My printer can't be found anymore.
I thought: OK I killed my Ubuntu account... then I will just create a new one and be more careful from now on ... no chance .. there is also no internet.
Should I reinstall Ubuntu?
Now I have always to do at start-up manually to be connected to the internet.
(update I only did dhclient -v
after reboot)
sudo dhclient -v
# and at first I also used the following cmd, but dhclient seems to be enough.
sudo ufw enable
So if nothing works, could I just switch to another account?
What I tried
- I didn't try much for not messing up that much
- I disabled ufw after enable and the internet still works (not surprising).
Firewall UFW status
sudo ufw status verbose
Status: Aktiv
Protokollierung: on (low)
Voreinstellung: allow (eingehend), allow (abgehend), deny (gesendet)
Neue Profile: skip
Zu Aktion Von
-- ------ ---
80,443/tcp (Apache Full) ALLOW IN Anywhere
137,138/udp (Samba) ALLOW IN Anywhere
139,445/tcp (Samba) ALLOW IN Anywhere
5050 ALLOW IN Anywhere
67,68/udp ALLOW IN Anywhere
69/udp ALLOW IN Anywhere
80,443/tcp (Apache Full (v6)) ALLOW IN Anywhere (v6)
137,138/udp (Samba (v6)) ALLOW IN Anywhere (v6)
139,445/tcp (Samba (v6)) ALLOW IN Anywhere (v6)
5050 (v6) ALLOW IN Anywhere (v6)
67,68/udp (v6) ALLOW IN Anywhere (v6)
69/udp (v6) ALLOW IN Anywhere (v6)
67,68/udp ALLOW OUT Anywhere
69/udp ALLOW OUT Anywhere
67,68/udp (v6) ALLOW OUT Anywhere (v6)
69/udp (v6) ALLOW OUT Anywhere (v6)
Ubuntu Version
lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 22.10
Release: 22.10
Codename: kinetic
Here you can see that on the Ubuntu GUI is no connection logo.

app list
sudo ufw app list
Verfügbare Anwendungen:
Apache
Apache Full
Apache Secure
CUPS
Samba
networkd.conf
GNU nano 6.4 /etc/systemd/networkd.conf
# the networkd.conf.d/ subdirectory. The latter is generally recommended.
# Defaults can be restored by simply deleting this file and all drop-ins.
#
# See networkd.conf(5) for details.
[Network]
#SpeedMeter=no
#SpeedMeterIntervalSec=10sec
#ManageForeignRoutingPolicyRules=yes
#ManageForeignRoutes=yes
#RouteTable=
[DHCPv4]
#DUIDType=vendor
#DUIDRawData=
[DHCPv6]
#DUIDType=vendor
#DUIDRawData=
/etc/netplan/01-network-manager-all.yaml
# Let NetworkManager manage all devices on this system
network:
version: 2
renderer: NetworkManager
dhcp4: true
nameservers:
addresses: [8.8.8.8, 8.8.4.4]
ruleset
sudo nft list ruleset
Here is a link to the output:
https://textdoc.co/KUmuSJRQFTgtPvqL
ip tables: https://justpaste.it/chb5k
$sudo iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
Chain FORWARD (policy DROP)
target prot opt source destination
DOCKER-USER all -- anywhere anywhere
DOCKER-ISOLATION-STAGE-1 all -- anywhere anywhere
ACCEPT all -- anywhere anywhere ctstate RELATED,ESTABLISHED
DOCKER all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere
LIBVIRT_FWX all -- anywhere anywhere
LIBVIRT_FWI all -- anywhere anywhere
LIBVIRT_FWO all -- anywhere anywhere
ufw-before-logging-forward all -- anywhere anywhere
ufw-before-forward all -- anywhere anywhere
ufw-after-forward all -- anywhere anywhere
ufw-after-logging-forward all -- anywhere anywhere
ufw-reject-forward all -- anywhere anywhere
ufw-track-forward all -- anywhere anywhere
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
Chain DOCKER (1 references)
target prot opt source destination
Chain DOCKER-ISOLATION-STAGE-1 (1 references)
target prot opt source destination
DOCKER-ISOLATION-STAGE-2 all -- anywhere anywhere
RETURN all -- anywhere anywhere
Chain DOCKER-ISOLATION-STAGE-2 (1 references)
target prot opt source destination
DROP all -- anywhere anywhere
RETURN all -- anywhere anywhere
Chain DOCKER-USER (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere
Chain LIBVIRT_FWI (1 references)
target prot opt source destination
ACCEPT all -- anywhere localhost/24 ctstate RELATED,ESTABLISHED
REJECT all -- anywhere anywhere reject-with icmp-port-unreachable
Chain LIBVIRT_FWO (1 references)
target prot opt source destination
ACCEPT all -- localhost/24 anywhere
REJECT all -- anywhere anywhere reject-with icmp-port-unreachable
Chain LIBVIRT_FWX (1 references)
target prot opt source destination
ACCEPT all -- anywhere anywhere
Chain LIBVIRT_INP (0 references)
target prot opt source destination
ACCEPT udp -- anywhere anywhere udp dpt:domain
ACCEPT tcp -- anywhere anywhere tcp dpt:domain
ACCEPT udp -- anywhere anywhere udp dpt:bootps
ACCEPT tcp -- anywhere anywhere tcp dpt:67
Chain LIBVIRT_OUT (0 references)
target prot opt source destination
ACCEPT udp -- anywhere anywhere udp dpt:domain
ACCEPT tcp -- anywhere anywhere tcp dpt:domain
ACCEPT udp -- anywhere anywhere udp dpt:bootpc
ACCEPT tcp -- anywhere anywhere tcp dpt:68
Chain ufw-after-forward (1 references)
target prot opt source destination
Chain ufw-after-input (0 references)
target prot opt source destination
ufw-skip-to-policy-input udp -- anywhere anywhere udp dpt:netbios-ns
ufw-skip-to-policy-input udp -- anywhere anywhere udp dpt:netbios-dgm
ufw-skip-to-policy-input tcp -- anywhere anywhere tcp dpt:netbios-ssn
ufw-skip-to-policy-input tcp -- anywhere anywhere tcp dpt:microsoft-ds
ufw-skip-to-policy-input udp -- anywhere anywhere udp dpt:bootps
ufw-skip-to-policy-input udp -- anywhere anywhere udp dpt:bootpc
ufw-skip-to-policy-input all -- anywhere anywhere ADDRTYPE match dst-type BROADCAST
Chain ufw-after-logging-forward (1 references)
target prot opt source destination
LOG all -- anywhere anywhere limit: avg 3/min burst 10 LOG level warning prefix "[UFW BLOCK] "
Chain ufw-after-logging-input (0 references)
target prot opt source destination
LOG all -- anywhere anywhere limit: avg 3/min burst 10 LOG level warning prefix "[UFW BLOCK] "
Chain ufw-after-logging-output (0 references)
target prot opt source destination
Chain ufw-after-output (0 references)
target prot opt source destination
Chain ufw-before-forward (1 references)
target prot opt source destination
ACCEPT all -- anywhere anywhere ctstate RELATED,ESTABLISHED
ACCEPT icmp -- anywhere anywhere icmp destination-unreachable
ACCEPT icmp -- anywhere anywhere icmp time-exceeded
ACCEPT icmp -- anywhere anywhere icmp parameter-problem
ACCEPT icmp -- anywhere anywhere icmp echo-request
ufw-user-forward all -- anywhere anywhere
Chain ufw-before-input (0 references)
target prot opt source destination
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere ctstate RELATED,ESTABLISHED
ufw-logging-deny all -- anywhere anywhere ctstate INVALID
DROP all -- anywhere anywhere ctstate INVALID
ACCEPT icmp -- anywhere anywhere icmp destination-unreachable
ACCEPT icmp -- anywhere anywhere icmp time-exceeded
ACCEPT icmp -- anywhere anywhere icmp parameter-problem
ACCEPT icmp -- anywhere anywhere icmp echo-request
ACCEPT udp -- anywhere anywhere udp spt:bootps dpt:bootpc
ufw-not-local all -- anywhere anywhere
ACCEPT udp -- anywhere 224.0.0.251 udp dpt:mdns
ACCEPT udp -- anywhere 239.255.255.250 udp dpt:1900
ufw-user-input all -- anywhere anywhere
Chain ufw-before-logging-forward (1 references)
target prot opt source destination
Chain ufw-before-logging-input (0 references)
target prot opt source destination
Chain ufw-before-logging-output (0 references)
target prot opt source destination
Chain ufw-before-output (0 references)
target prot opt source destination
ACCEPT all -- anywhere anywhere
ACCEPT all -- anywhere anywhere ctstate RELATED,ESTABLISHED
ufw-user-output all -- anywhere anywhere
Chain ufw-logging-allow (0 references)
target prot opt source destination
LOG all -- anywhere anywhere limit: avg 3/min burst 10 LOG level warning prefix "[UFW ALLOW] "
Chain ufw-logging-deny (2 references)
target prot opt source destination
RETURN all -- anywhere anywhere ctstate INVALID limit: avg 3/min burst 10
LOG all -- anywhere anywhere limit: avg 3/min burst 10 LOG level warning prefix "[UFW BLOCK] "
Chain ufw-not-local (1 references)
target prot opt source destination
RETURN all -- anywhere anywhere ADDRTYPE match dst-type LOCAL
RETURN all -- anywhere anywhere ADDRTYPE match dst-type MULTICAST
RETURN all -- anywhere anywhere ADDRTYPE match dst-type BROADCAST
ufw-logging-deny all -- anywhere anywhere limit: avg 3/min burst 10
DROP all -- anywhere anywhere
Chain ufw-reject-forward (1 references)
target prot opt source destination
Chain ufw-reject-input (0 references)
target prot opt source destination
Chain ufw-reject-output (0 references)
target prot opt source destination
Chain ufw-skip-to-policy-forward (0 references)
target prot opt source destination
DROP all -- anywhere anywhere
Chain ufw-skip-to-policy-input (7 references)
target prot opt source destination
DROP all -- anywhere anywhere
Chain ufw-skip-to-policy-output (0 references)
target prot opt source destination
ACCEPT all -- anywhere anywhere
Chain ufw-track-forward (1 references)
target prot opt source destination
Chain ufw-track-input (0 references)
target prot opt source destination
Chain ufw-track-output (0 references)
target prot opt source destination
ACCEPT tcp -- anywhere anywhere ctstate NEW
ACCEPT udp -- anywhere anywhere ctstate NEW
Chain ufw-user-forward (1 references)
target prot opt source destination
Chain ufw-user-input (1 references)
target prot opt source destination
ACCEPT tcp -- anywhere anywhere tcp dpt:ssh
ACCEPT tcp -- anywhere anywhere tcp dpt:http
ACCEPT tcp -- anywhere anywhere tcp dpt:https
Chain ufw-user-limit (0 references)
target prot opt source destination
LOG all -- anywhere anywhere limit: avg 3/min burst 5 LOG level warning prefix "[UFW LIMIT BLOCK] "
REJECT all -- anywhere anywhere reject-with icmp-port-unreachable
Chain ufw-user-limit-accept (0 references)
target prot opt source destination
ACCEPT all -- anywhere anywhere
Chain ufw-user-logging-forward (0 references)
target prot opt source destination
Chain ufw-user-logging-input (0 references)
target prot opt source destination
Chain ufw-user-logging-output (0 references)
target prot opt source destination
Chain ufw-user-output (1 references)
target prot opt source destination