I have only recently noticed our Ironport devices are several minutes out of sync with the atomic clock. After investigating the issue i found that although they are pointed to the time.ironport.com NTP server, our firewall is currently blocking this traffic.
Before making any firewall changes, i was wondering are there any big concerns or security vulnerabilities i should know about over allowing this kind of traffic through udp port 123 on our firewall? Or is it recommended to just set the time manually?
Any advice/information would be much appreciated