it could download the database updates for the system packages; but could not retrieve the packages and hung up. I found that
wgetwas able to use the proxy fine. So, I tried
pacman --debug -S mkvtoolnix
to see what was happening and found that it was stuck after detecting the proxy. As
wgetwas working, I tried uncommenting the following line in
#XferCommand = /usr/bin/wget --passive-ftp -c -O %o %u
This time the upgrade was smooth and I upgraded 66 packages.