Linux maintains bugs: The real reason ifconfig on Linux is deprecated (2018)
Huh?!?<p>I use multiple addresses a lot, and recall having used them through ifconfig for years, probably well over a decade.
Anyway, at least on Debian, the package net-tools brings ifconfig it back, again with full multiple addresses support.<p><pre><code>  # uname -v
  #1 SMP Debian 5.4.19-1 (2020-02-13)


  # ifconfig
  enp2s0: flags=4163&lt;UP,BROADCAST,RUNNING,MULTICAST&gt;  mtu 1500
        inet 192.168.10.42  netmask 255.255.255.0  broadcast 192.168.10.255
        inet6 fe80::2e4d:54ff:fed8:7b59  prefixlen 64  scopeid 0x20&lt;link&gt;
        ether 2c:4d:54:d8:7b:59  txqueuelen 1000  (Ethernet)
        RX packets 1162942  bytes 1627138668 (1.5 GiB)
        RX errors 0  dropped 42049  overruns 0  frame 0
        TX packets 546159  bytes 41181499 (39.2 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

  lo: flags=73&lt;UP,LOOPBACK,RUNNING&gt;  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10&lt;host&gt;
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 16  bytes 818 (818.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 16  bytes 818 (818.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0


  # ifconfig enp2s0:1 192.168.1.42

  # ifconfig
  enp2s0: flags=4163&lt;UP,BROADCAST,RUNNING,MULTICAST&gt;  mtu 1500
        inet 192.168.10.42  netmask 255.255.255.0  broadcast 192.168.10.255
        inet6 fe80::2e4d:54ff:fed8:7b59  prefixlen 64  scopeid 0x20&lt;link&gt;
        ether 2c:4d:54:d8:7b:59  txqueuelen 1000  (Ethernet)
        RX packets 1163011  bytes 1627147417 (1.5 GiB)
        RX errors 0  dropped 42089  overruns 0  frame 0
        TX packets 546185  bytes 41184061 (39.2 MiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

  enp2s0:1: flags=4163&lt;UP,BROADCAST,RUNNING,MULTICAST&gt;  mtu 1500
        inet 192.168.1.42  netmask 255.255.255.0  broadcast 192.168.1.255
        ether 2c:4d:54:d8:7b:59  txqueuelen 1000  (Ethernet)

  lo: flags=73&lt;UP,LOOPBACK,RUNNING&gt;  mtu 65536
        inet 127.0.0.1  netmask 255.0.0.0
        inet6 ::1  prefixlen 128  scopeid 0x10&lt;host&gt;
        loop  txqueuelen 1000  (Local Loopback)
        RX packets 16  bytes 818 (818.0 B)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 16  bytes 818 (818.0 B)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0</code></pre>