Forum Cannot Login to Forum w/o Check to Remember Following DNS Change
 

I am having an issue where I changed the @ and www records in my DNS zone file to a new IP. The old IP was to a DDOS service that stood in front of my forum and the new IP is the outside IP of my Varnish cache server that is in front of my two webservers. Before the change, logins worked with and without using www and without requiring the checkmark to remember. After the change in IP in DNS, the only way to login is to use the checkmark option at login. All servers are the same, no change in domain name and the only change was to remove the old DDOS service IP from RPAF in the httpd.conf file. I have tried toggling the settings in cookie domain with no change. I'm pretty certain this is a cookie issue, but am not sure where to find or correct the issue. Has anyone seen this? Any help or direction is greatly appreciated.