I had a customer yesterday that was trying to set up Asterisk on a Fasthosts dedicated server. This was working well apart from inbound calls from a specific DID/DDI provider. It turned out that the call provider was also using a Fasthosts dedicated server and that traffic between Fasthosts dedicated servers is blocked (although some basic ports are allowed – 22,25,53 and 80 just to confuse things even more!).
This meant that the SIP traffic going from the call provider to the customers Asterisk server was being blocked.
Fasthosts helpdesk confirmed that this is the case and the usual solution suggested is to set up a private LAN between the 2 servers. However this is only possible where both servers are owned by the same customer, which is obviously not the case here.
Does anyone know the reason for this policy? This is the second customer I’ve seen in the past few months where this has caused an issue. I can’t think of a logical reason. Thanks!