Ubuntu Unleashed 2019 Edition: Covering 18.04, 18.10, 19.04

Set NIC

promiscuous

[-]promisc ifconfig eth0    promisc mode

on  [off]

[ifconfig   eth0    -

promisc]

Set

multicasting

mode

[-]allmulti ifconfig    eth0_on [off]

allmulti    [ifconfig   eth0    -

allmulti]

Enable  or

disable

[-]pointopoint

[address]

eth0_pointopoint

ifconfig_point-to-point

address 10.10.10.20

[ifconfig   eth0

pointopoint_10.10.10.20]

The ifconfig man page shows other options that enable your machine to
interface with a number of network types, such as AppleTalk, Novell, IPv6,
and others. Again, read the man page for details on these network types.

NOTE

Promiscuous mode    causes  the NIC to  receive all packets on  the network.    It

is  often   used    to  sniff   a   network.    Multicasting    mode    enables the NIC to

receive all multicast   traffic on  the network.

If no argument is given, ifconfig displays the status of active interfaces.
For example, the output of ifconfig, without arguments and one active and
configured NIC, looks similar to this:

Click here to view code image
matthew@seymour:~$ ifconfig
eth0 Link encap:Ethernet HWaddr 00:90:f5:8e:52:b5
UP BROADCAST MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)
Interrupt:30 Base address:0xc000
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:314 errors:0 dropped:0 overruns:0 frame:0
TX packets:314 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:25204 (25.2 KB) TX bytes:25204 (25.2 KB)