I just tried a CentOS server, new install. Same error. :\
I just tried a CentOS server, new install. Same error. :\
I install ZCS on CentOS (various flavours and architectures) on a regular basis without problems, it's one of the easier installations. Do you actually have SElinux & the firewall disabled on this server (you should)? Do you have the current ZCS 8.x installed and by implication this would be a 64bit server? Is this a VM and if so, which hypervisor? Is this a hosted server somewhere and if so, who is the hosting provider? Just for confirmation, go to the Split DNS article and provide the output from all the commands in the 'Verify....' section.
[EDIT]Do you also have IPv6 enabled on this server? Also provide the status of the ZCS services and any errors you see in the log files when ZCS starts.
That doesn't make any difference, the MX record then points to an A record which can be a different IP address than your web server (forum?) IP address. I've also just noticed that your external DNS records have changed and they are now incorrect for the mail server (MX record). I've already asked you this but can you confirm if your server is actually behind a NAT router or is it just on a Public IP and does it have the firewall enabled?
Seems that you have the same problem as me if you have apache server installed is not going to function, I've try several time with ubuntu 10.04 12.xx and so on as soon I've got back to the 32 bits server and zimbra 7.2 everything is working without problem. As soxfan explain to me in that threat http://www.zimbra.com/forums/install...ng-apache.html isn't going to function in the new versions. I've asked for help to solve that problem but nobody has answered.