====== Ubuntu ======


===== User administrieren =====

<code bash>
#create new user 'newuser'
sudo adduser newuser 

#show current groups
groups newuser

#Public Key in ''~/.ssh/authorized_keys'' eintragen

#grand sudo rights (by adding user to group sudo)
sudo usermod -aG sudo newuser

#deletes user and removes home directory
sudo deluser --remove-home newuser
</code>


===== Hostname ändern =====

<code bash>
sudo hostnamectl set-hostname NEUERNAME
</code>

===== Manuelle Netzwerkonfiguration (Netplan) =====

1. Netzwerkinterface herausfinden (:!:muss in der Config angepasst werden!):
<code bash>
ip link
</code>

2. Datei ''/etc/netplan/01-netcfg.yaml'' anlegen/bearbeiten:
<code yaml>
network:
  version: 2
  renderer: networkd
  ethernets:
    ens3:
      dhcp4: no
      addresses:
        - 141.45.184.42/25
      routes:
        - to: default
          via: 141.45.184.1
      nameservers:
          addresses: [8.8.8.8, 9.9.9.9]
</code>

3. Zugriff beschränken:
<code bash>
chmod 600 /etc/netplan/01-netcfg.yaml
</code>

3. Netplan anwenden und Config überprüfen:
<code bash>
sudo netplan apply
ip addr show dev ens3
</code>

===== DNS-Server konfigurieren (ohne Netplan) =====

Create:
<code bash>
sudo mkdir /etc/systemd/resolved.conf.d/
sudo vim /etc/systemd/resolved.conf.d/dns_servers.conf
</code>

Insert lines into ''dns_servers.conf'':
<code bash>
[Resolve]
DNS=9.9.9.9 8.8.8.8
</code>

Restart ''systemd-resolved'':
<code bash>
sudo systemctl restart systemd-resolved
</code>

Source: https://askubuntu.com/questions/1406827/how-to-set-dns-on-ubuntu-22-04-when-you-have-no-netplan-config


===== Wake-on-LAN konfigurieren =====

  * https://kodi.wiki/view/HOW-TO:Set_up_Wake-on-LAN_for_Ubuntu#cite_note-1
:!: WoL als Systemd - Service (16.04): 
  * https://askubuntu.com/questions/764158/how-to-enable-wake-on-lan-wol-in-ubuntu-16-04
  * [[https://apple.stackexchange.com/questions/95246/wake-other-computers-from-mac-osx|Python Script für MagicPacket]]

===== Verschlüsselung der Home-Partition aufheben: =====

  * https://askubuntu.com/questions/107410/can-you-unencrypt-remove-encryption-from-a-user-home-folder
  * http://virtually-a-machine.blogspot.com/2010/08/howto-disable-ecryptfs.html
:!: vor dem Kopieren muss das Home-Verzeichnis schreibbar gemacht werden (Permissions: 700)


===== Hardening Ubuntu: =====

  * https://gist.github.com/lokhman/cc716d2e2d373dd696b2d9264c0287a3
  * https://bookofzeus.com/harden-ubuntu/hardening/sysctl-conf/
===== IPv6 in Ubuntu manuell konfigurieren =====
==== Zielkonfiguration ====


''2001:db8:333::2/64 auf eth0\\ 
2001:db8:333::1/64 ist der Router/Gateway''

==== IPv6-Adresse an Interface binden ====

Enable IPv6 (wenn nötig): ''$ sudo modprobe ipv6''

<code bash>sudo ip addr add 2001:db8:333::3/64 dev eth0</code>
oder:
<code bash>sudo ip -f inet6 address add 2001:db8:333::3/64 dev eth0</code>


==== Default Route eintragen ====

<code bash>sudo ip -6 route add ::/0 via 2001:db8:333::1</code>

==== Konfiguration prüfen ====
Anzeigen der an die Interfaces gebundenen Adressen:
<code bash>ip a</code>
Anzeigen der Routen
<code bash>netstat -6nr # IPv6 Routen
netstat -nr # IPv4 Routen</code>