Networking utilities and tools: DNS and addresses

DNS and addresses

Files

Debian family: /etc/network

SUSE family: /etc/sysconfig/network

Basic and omnipresent network utilities

nmtui is the GUI utility independent from the desktop environment, working on the shell.
nmcli is the command line utility.
Ubuntu uses netplan.

IP utility

$ /sbin/ip addr show
Diplays the IP address of the machine

$ /sbin/ip route show
Displays the routing information

Dynamic Host Configuration Protocol Client - dhclient
Utility to set and manage dynamic IP

Route

Route manage the routing table, which displays the correlation of final destinations with the next hop addresses.

$ route –n
or

$ ip route
Shows current routing table

$ route add -net address
or

$ ip route add

Add static route

$ route del -net address

or

$ ip route del

Delete static route

Traceroute

Traceroute inspects the route taken by the data packet to reach the destination host. Used for delays and errors network troubleshooting . It can isolate connectivity issues between hops.

$ traceroute <address>

Other networking tools

ethtool
Queries network interfaces and can also set various parameters such as the speed

netstat
Displays all active connections and routing tables; useful for monitoring performance and troubleshooting

nmap
Scans open ports on a network; important for security analysis

tcpdump
Dumps network traffic for analysis

iptraf
Monitors network traffic in text mode

mtr
Combines functionality of ping and traceroute and gives a continuously updated display

dig
Tests DNS workings; a good replacement for host and nslookup

$ /etc/ifconfig [options]
Visualises and configures network interfaces