After installing WHM on EC2 I started to setup the individual CPanel accounts with FTP accounts.
When trying to connect via FTP with a new account I got the following error with Filezilla:
‘Failed to Retrieve Directory Listing’
From carrying out some research it turns out that a range of passive ports need to be added to your Security Group. To find the passive port range used by Pure-FTP, shell into the servers and run the following:
Search for Passive and you should see (version 60 of WHM):
PassivePortRange 49152 65534
Add this port range (49152 – 65534) to your Security Group and test with FileZilla.
* Make sure ForcePassiveIP is set to the correct external IP
**Try to lock down the passive port range to an IP range where possible