i have an issue on my Moodle 31 (which installed on CentOS 6.8, PHP 5.6) and enabled https in side Moodle server itself and using essential theme.
my Moodle is working fine without any problem when accessing it directly, but the issue came when redirecting the connections to be via F5 BIG IP. we have created vIP address and when changing DNS to new vIP (which will rout the connections from client browser --> F5 --> web server and vise versa) some images in Moodle are disappeared.
here is an example of images which disappeared
Before redirecting
After redirecting via F5
when I checked the URL of those hidden images it shows me those links
https://mymoodle.com/theme/image.php/essential/core/1507105255/t/block_to_dock
https://mymoodle.com/theme/image.php/essential/core/1507105255/t/switch_plus
https://mymoodle.com/theme/image.php/essential/core/1507105255/t/switch_minus
If I copy and paste the above URL in new tab, it shows me the following page
any clues to solve this problem ??