The paths are like this: https://example.com/10001/5235723gdh.jpg
https://example.com/10007/836789370md.jpg We want to extract the number in the middle and compare. I tried with acl image1 path_reg \/[0-9]*\/.* le 10005 acl image2 path_reg \/[0-9]*\/.* ge 10006 use_backend image1 if image1 use_backend image2 if image2 But it is not working. How can I make this working? I know i can probably use lua script but I rather want to achieve this using ACL only if that is possible. Thank You.