This question already has an answer here:
Currently I have the following setup with two hostnames and two ips:
cheeze1.mydomain.com IN A 22.214.171.124 126.96.36.199.in-addr.arpa IN PTR cheeze1.mydomain.com cheeze2.mydomain.com IN A 188.8.131.52 184.108.40.206.in-addr.arpa IN PTR cheeze2.mydomain.com
I want to change to having a round-robin dns for a single hostname using the two ips. Are the following PTR records valid? Can a host have multiple IPs and with each having valid reverse dns resolution?
cheezeonly.mydomain.com IN A 220.127.116.11 cheezeonly.mydomain.com IN A 18.104.22.168 22.214.171.124.in-addr.arpa IN PTR cheezeonly.mydomain.com 126.96.36.199.in-addr.arpa IN PTR cheezeonly.mydomain.com
EDIT: Please note that this question isn't asking the same as suggested in comments.
I'm going to answer this one myself, you guys are no help marking it as duplicate and not reading the question properly. Hopefully this answer will help others.
Yes, it is valid, and yes it will pass a FcRDNS check.
From the "Pro DNS and BIND" book: http://www.zytrax.com/books/dns/ch9/rr.html
An alternate approach is to define multiple A records with the same mail server name: ; zone file fragment IN MX 10 mail.example.com. .... mail IN A 192.168.0.4 IN A 192.168.0.5 IN A 192.168.0.6
In this case the load-balancing effect is under the control of BIND and the rrset-order record. In order to avoid problems if the receiving mail system does reverse look-up as a spam check then the PTR records for 192.168.0.4, 192.168.0.5, 192.168.0.6 above must all define (resolve to) mail.example.com.
And from RFC1912: Common DNS Operational and Configuration Errors
"For every IP address, there should be a matching PTR record in the in-addr.arpa domain. If a host is multi-homed, (more than one IP address) make sure that all IP addresses have a corresponding PTR record (not just the first one). Failure to have matching PTR and A records can cause loss of Internet services similar to not being registered in the DNS at all. " –
Therefor this configuration is valid and passes FcRDNS checks.