On which Linux distribution did you find the "This program is obsolete!" note in...

cmurf · on Sept 14, 2017

Fedora 26.

    $ sudo dnf provides /usr/sbin/ifconfig
    net-tools-2.0-0.42.20160912git.fc26.x86_64 : Basic networking tools
    Repo        : @System

jwilk · on Sept 14, 2017

https://git.centos.org/raw/rpms/net-tools.git/c7/SOURCES!net...

I believe this patch originates from Fedora, but I don't know how to get Fedora source for this RPM. :-\

boomboomsubban · on Sept 14, 2017

Go install ifconfig somehow and try again, Debian ships with a wrapper I believe.

kelnos · on Sept 14, 2017

Not a wrapper, it seems:

    $ file /sbin/ifconfig 
    /sbin/ifconfig: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.32, BuildID[sha1]=6bf40c44a9b42715a7670365936e6d0aa16f7bf1, stripped
    $ dpkg -S /sbin/ifconfig
    net-tools: /sbin/ifconfig

And my man page does not show anything about it being obsolete (Debian buster).