Hi,
By default dnf assumes that you have internet access from the AIX.
Either there is no proxy configured in /opt/freeware/etc/dnf/dnf.conf or you have to create a local RPM repo either by "dnf createrepo" or mirroring aixtoolbox to a local server, when you have RPM packages on the server, then you have configure some http daemon on that server.
Both Apache httpd and nginx are available in the AIX toolbox.
There was a discussion regarding RPM repos in AIX Open source group.
Br. Esa
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Esa Kärkkäinen
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