There seems to be an awful lot of the same types of errors in the forums pertaining to DNS, SSL, etc.
It might be handy to have scripts built-in that diagnose these types of issues. It would simply report if your /etc/hosts is wrong or if split-DNS is improperly configured or if SSH keys don't match or if there is no SSL cert or the SSL certs don't match or whatever. I had an issue where the passwords in LDAP weren't what were in the config file. Easy to check for, but takes a long time to get to that point when digging through dozens of the same forum posts that aren't the issue.