So I was banging my head on the common issue of:
ERROR: Installation can not proceeed. Please fix your /etc/hosts file to contain:
127.0.0.1 localhost.localdomain localhost
I had followed all the set up recommendations
hostname --fqdn ... was fine
/etc/hosts .. was fine the localhost entry was correct, the format was fqdn shortname
/etc/resolv.conf .. was good with my split dns first
dig yourdomain.com mx .. fine
dig yourdomain.com any ... fine
host `hostname` ... fine
I was pulling out my hair wondering what the heck it was.
So I looked at the code and saw that what the script checks for is getent hosts.
So I ran the command and saw some weird entries...
So that put me on the right track... The issue was that I was running nscd, and it had cached old values of my hosts file.
I flushed nscd with nscd -i hosts, and it works like a charm.
I figured that might save someone a few headaches down the road