DNS resolver should not be case sensitive
I'm totally new here, so I'd like to say kindly hello to the project team in first.
I installed foreman on a bare metal installed CentOS7 like described in your documentation and faced against a minor bug in foreman-installer prerequsites.
The installer already fails if the hostname is case-sensitive for forward and reverse resolution only.
[root@FOREMAN ~]# foreman-installer -i
Reverse DNS foreman.testlab.site.example.local does not match hostname FOREMAN.testlab.site.example.local
Your system does not meet configuration criteria
[root@FOREMAN ~]# host FOREMAN.testlab.site.example.local
FOREMAN.testlab.site.example.local has address 10.20.30.40
[root@FOREMAN ~]# host 10.20.30.40
22.214.171.124.in-addr.arpa domain name pointer foreman.testlab.site.example.local.
DNS names should not be case sensitive.
See also here
http :// tools.ietf.org/html/draft-vixie-dnsext-dns0x20-00
https :// developers.google.com/speed/public-dns/docs/security?csw=1#randomize_case
As a workaround I added following line to /etc/hosts
10.20.30.40 esh-mgmtsrv01-t foreman.testlab.site.example.local
After the workaround the installer succeeded
#1 Updated by Ewoud Kohl van Wijngaarden over 2 years ago
- Triaged changed from No to Yes
- Category set to foreman-installer script
- Found in Releases 1.20.0 added
The offending check appears to be https://github.com/theforeman/foreman-installer/blob/575a642380833b4a4b1ca9d186e8ded26b4fd831/checks/dns.rb#L29
If you wrap the hostnames in Resolv::DNS::Name.create() you use Ruby's DNS-aware comparisons:
 pry(main)> Resolv::DNS::Name.create("y.z") == Resolv::DNS::Name.create("Y.Z") => true
This would be a great first contribution :)
Note we recently added a check to prevent uppercase hostnames. This was mostly motivated by Katello because these kind of bugs show up in more places.
That said, IMHO we should support this because the RFCs allow it.