“CURL ERROR 7 Failed to connect to Permission denied” error is caused, when for any reason curl request is blocked by some firewall or similar thing.
you will face this issue when ever the curl request is not with standard ports.
for example if you do curl to some URL which is on port 1234, you will face this issue where as URL with port 80 will give you results easily.
Most commonly this error has been seen on CentOS and any other OS with ‘SElinux’.
you need to either disable or change ‘SElinux’ to permissive
locate following line
Change this to
reboot is needed