Downloading Cntlm Before It Can Help the Package Manager
Break the download dependency by fetching the correct RPM through an already working authenticated client, then account for package-manager dependencies separately.
If the package manager cannot authenticate to the office proxy, asking it to download Cntlm creates a dependency loop: the helper is needed for the route that would fetch the helper.
An already working curl client can provide the first download. For an NTLM proxy, curl’s --proxy-ntlm option selects authentication with the proxy; --ntlm selects authentication with the remote destination instead. Supply the proxy account through curl’s credential configuration.
Fetch the Cntlm RPM built for the installed distribution release and architecture from its trusted package source. A historical answer’s direct Fedora package URL describes that release’s package; it is not a current universal installer address.
A local RPM can still leave network work
Downloading the helper package and resolving its dependencies are separate tasks. Do not infer that the current package has no dependencies because one older RPM did not need additional downloads on another machine.
On a DNF-based system, the documented local-file form is:
dnf install ./cntlm.rpmUse the downloaded file’s actual name and the appropriate installation privileges. DNF can still need repository metadata or missing dependency packages. If that network path remains unavailable, obtain the required packages for the same release through the approved working route, keeping the distribution’s normal package-verification policy.
Once the helper is installed and configured, the package manager can use its local listener for later requests. That listener does not exist merely because an RPM file has been saved, and its loopback address is meaningful only on the machine running the helper.