Topic 205: Networking Configuration

Kursvorgaben LPI:

Topic 205: Networking Configuration

205.1 Basic networking configuration (weight: 3)

Candidates should be able to configure a network device to be able to connect to a local, wired or wireless, and a wide-area network. This objective includes being able to communicate between various subnets within a single network including both IPv4 and IPv6 networks.

Key Knowledge Areas

• Utilities to configure and manipulate ethernet network interfaces
• Configuring basic access to wireless networks with iw, iwconfig and iwlist

The following is a partial list of the used files, terms and utilities

quagga

frrouting

• /etc/frr/frr.conf

BIRD

RIPng ist RIP für ipv6

• layer
• 1 Betriebssystem
• lsmod lspci dmesg ip link
• 2 Etherntet Wifi PPP...
• ip link
• ethtool
• iw
• AP, MAC, Paket
• 2,5 ARP
• ip -4 neighbor show
• 3
• IP Adress, Subnetz, Router
• v6
• ip route -6
• fe80 link local adresses
• ff02::2 nächste router // ist admin spezifisch. fest vergeben.  kein std
• 2600::
• ULA fc und fd
• radvd // router advertisement deamon
• v4
• ip address
• ip route
• ip
• ip link
• ip --br link // single line version
• ifconfig
• route
• arp
• iw
• iwconfig
• iwlist
• iwl??
• nmcli device set wlp... managed no
• rfkill
• rfkill list
• soft block
• hard block
• rfkill unblock 1
• ip link set up dev wlp...
• iw dev wlp... scan
• iw dev ... connectt -w linuxhotel

Beispiele

• netzwerk
• ipv6
• three-subnets
• wlan
• routing

205.2 Advanced Network Configuration (weight: 4)

Candidates should be able to configure a network device to implement various network authentication schemes. This objective includes configuring a multi-homed network device and resolving communication problems.

Key Knowledge Areas

• Utilities to manipulate routing tables
• Utilities to configure and manipulate ethernet network interfaces
• Utilities to analyse the status of the network devices
• Utilities to monitor and analyse the TCP/IP traffic

The following is a partial list of the used files, terms and utilities

• ip
• ifconfig
• route
• arp
• ss
• netstat
• lsof
• ping, ping6
• nc
• tcpdump
• nmap

Beispiele

• tcpdump
• netstat / ss

205.3 Troubleshooting network issues (weight: 4)

Candidates should be able to identify and correct common network setup issues, to include knowledge of locations for basic configuration files and commands.

Key Knowledge Areas

• Location and content of access restriction files
• Utilities to configure and manipulate ethernet network interfaces
• Utilities to manage routing tables
• Utilities to list network states.
• Utilities to gain information about the network configuration
• Methods of information about the recognised and used hardware devices
• System initialisation files and their contents (Systemd and SysV init)
• Awareness of NetworkManager and its impact on network configuration

The following is a partial list of the used files, terms and utilities

• ip
• ifconfig
• route
• ss
• netstat
• /etc/network/, /etc/sysconfig/network-scripts/
• ping, ping6
• traceroute, traceroute6
• traceroute -T -p 80
• -I icmp
• mtr
• hostname
• System log files such as /var/log/syslog, /var/log/messages and the systemd journal
• dmesg
• /etc/resolv.conf
• /etc/hosts
• /etc/hostname, /etc/HOSTNAME
• /etc/hosts.allow, /etc/hosts.deny
• cat /etc/nsswitch.conf | grep hosts
• libnss_files.so.2
• libnns_dns << ließt die /etc/resolv.conf
• getent hosts www.linuxhotel.de
• getent ahosts
• getent ist immer lokal; dig verwenden nicht die nsswitch bibo
• nss-myhostname
• mdns
• hosts: files myhostname mdns_minimal [NOTFOUND=return] mymachines dns
• dig nimmt als fallback /etc/resolf.conf
• getent hält sich an die einstellungen /etc/nsswitch.conf
• .internal einzige die nicht irgendwann verkauft wird

Beispiele

• tcpwrapper
• netstat
• udev
• netzwerk
• dns

205.1 Basic networking configuration

WIFI

nmcli device set wlp0s20f3 managed no

root@notebook24:~# rfkill list
0: tpacpi_bluetooth_sw: Bluetooth
	Soft blocked: no
	Hard blocked: no
1: hci0: Bluetooth
	Soft blocked: no
	Hard blocked: no
2: phy0: Wireless LAN
	Soft blocked: no
	Hard blocked: no

Connect geht nur mit iwl oder wpa_supplicant, da iw ausschließlich unverschlüsselte WLANs verbinden kann.

Arbeiten mit der VM3

IPv4 Konfiguration

Diese gesetzte Konfiguration ist NICHT reboot fest!

Jetzt ist es reboot fest :D Interfaces, weil Debian 12!

Routing

Für das LAB mit FRR einen RIP Router konfiguriert:

IPv6 Konfiguration

ULA

RADVD

Auf dem Notebook:

apt install radvd

wichtige Ergänzung, damit beim shutdown des RADVD die Präfixe verworfen werden:

DeprecatePrefix on; # Beim Stoppen von radvd soll das Prefix auf eine Lifetime=0 gesetzt werden und beim Client auf deprecated markiert werden.

Auf der VM:

apt install ndisc6