CloudLinux hides specific processes from users, which results in the FTP Connections not displaying within the cPanel interface. More details can be found about the CloudLinux virtualized /proc mount here:
Other details about this case can be found in our forum here:
The only known workaround at this time is to disable /proc hidepid=2 option or set fs.proc_can_see_other_uid=1 on CloudLinux, but this is NOT RECOMMENDED as it bypasses a significant security feature.
1. Verify this is the case by checking the for the setting 'hidepid=2' in the proc mount.
grep proc /proc/mounts
2. You can correct this by disabling this security setting that was added. This is caused by the following value "fs.proc_can_see_other_uid=0" inside the file '/etc/sysctl.conf' (NOTE: This is a CloudLinux-specific setting and indirectly affects hidepid /proc mount option at boot, the /proc option must be changed directly on CentOS systems).
3. This value cannot be temporarily set, as a remount of Cagefs resets the sysctl settings to the conf. This value needs to be changed inside the file, and of course, we need to make a backup.
sed -i.cpbak 's/fs.proc_can_see_other_uid=0/fs.proc_can_see_other_uid=1/' /etc/sysctl.conf
4. Once the value is changed, we have to apply this to the system and also remount proc. Luckily Cloudlinux provides a py script for the remount.
After performing the above steps, FTP Connections should be displaying properly within the cPanel interface.