While trying to upgrade cpanel  to new version was getting error

FATAL: Failed to download updatenow.static from server:

The issue was due to corrupt RPM

I used the below fix to resolve this issue

mkdir /root/old_rpm_dbs/

Now move the original RPMs to the new folder

mv /var/lib/rpm/__db* /root/old_rpm_dbs/

Finally rebuild the RPM database

rpm --rebuilddb

Now you can force an update of the cPanel server and it should work again.

/scripts/upcp -force