diff --git a/vpnsetup.sh b/vpnsetup.sh
index e996aa3..255af9b 100644
--- a/vpnsetup.sh
+++ b/vpnsetup.sh
@@ -45,6 +45,9 @@ VPN_PASSWORD=your_very_secure_password
 # iPhone/iOS users may need to replace this line in ipsec.conf:
 # "rightprotoport=17/%any" with "rightprotoport=17/0".
 
+# If using Amazon EC2, these ports must be open in the security group
+# of your VPN server: UDP ports 500 and 4500, and TCP port 22 (for SSH).
+
 # In Amazon EC2, these two variables will be found automatically
 # For all other servers, you MUST replace them with the actual IPs!
 # If your server only has a public IP, use that IP on both lines