This is an easy test to verify whether your ports are opened at C-Servers… servers.
Bear in mind that some ports will appear as closed, despite being open, if there is no traffic currently trying to come through them. This is standard practice for many applications, for security reasons.
This is the configuration of our port forwarding services:
HostOne (web hosting) – not supported, with the exception of SFTP;
MultiVPS (main VPS) – restricted by default at port 25 (Standard SMTP), 111 (RPC PortMapper), 465 (SSL, SMTP) and 587 (TLS, SMTP). ICMP communication is restricted from the outside.
MultiNAT (IPv4 NAT VPS) – restricted at all ports below 10000, except 80 and 443.
