ufff...
Ok let me explain a little.
The "outside":
the domain is declared at TLD with the two IP's as nameservers for my domain.
I have two ISP's that have given me two public IP's.
Zentyal is used for the following roles:
DNS; Mail; Webserver; Gateway;
at the network section of zentyal i've declared:
Eth 1 - IP from isp1
Eth 2 - IP from isp2
Eth 0 - Lan ip;
Enabled the wan failover monitor;
Declared the primary gateway from isp1;
Enable load balance on external interfaces with 50/50;
On the DNS section of zentyal:
Create the domain.com;
Add both ip's from ISP to the domain.com;
Add the forwarders from my ISP;
in the host section of the domain (SRV01) i've added the two IP's
In alias section i've added the proper aliases.
Then configured the firewall and that was it ... more or less:)
But now i have wan fail over for my lan subnet.
and the server is reachable from each ISP because it is responding with two IP when domain is asked.
For the rDNS i've asked the IPS's help so that the ip's alocated to me will resove properly on their end. so for example a traceroute will resolve to the proper ip/name from my ISP. (i'm not well versed in rDNS and FCrDNS so that's why i've asked for their help)
I know what BGP stands for and is not so easily to implement. A few years i've did (with outside help of course since i'm not all-knowing ) a BGP configuration with AS and everything, but that was when i needed proper load balancing between 4 ISP and it was for a small neighborhood and I was the local ISP. But this is not the case and Zentyal is perfect for rr loadbalance.
I have both HA for reaching the servers on different isp and wan failover for LAN side.
The round robin is done internaly by zentyal you however can specify if you want, how much of the total queries can be on put on one interface and how much on the other.
My DNS setup is done correct (i hope:) ) on my end but the rdns i've asked for help on my ISP (not registrar since it is registered ar TLD)
Best regards
Bogdan