We have tested network accessibility from our test POPs and found that the IP is blocked by GFW.
While the IP is blocked by GFW the VPS stays fully operational, however you will not be able to migrate the VPS to a different datacenter until the ban is removed.
It is quite easy to verify if your VPS IP was banned by the Great Firewall of China. When you use ping.pe to test your VPS IP you may see the following output:
As you can see, the VPS responds normally from all countries except for China, where we observe 100% packet loss. If you open up the mtr report, you will find an output similar to this:
This output may be a bit confusing at first. One would think if an IP was being blocked by a firewall then a traceroute or mtr report would start showing packetloss right after China (where firewalling takes place), however in the above example we can clearly see that only the last hop is affected. This is because GFW is set up so that only return traffic from a certain IP located outside of China is blocked. In other words, GFW does not track packets leaving China; it only tracks packets heading back into China. This means that when you perform a traceroute, only ICMP response packets sent by the last hop (final destination IP) back into China will be affected by firewall. Intermediary hops will not be affected.
We found that generally GFW automatically removes the ban when it can no longer detect the “prohibited” service for a few hours to a few days. The best solution in the case of a ban would be the complete removal of all service(s) that could trigger the ban and waiting for some time for the ban to be lifted.
Please keep in mind that we do not have any control over GFW, and we do not know much about how it works. It is our responsibility to make sure our hardware and network stay fully operational, and GFW-related issues are out of scope of our competence.
Some customers end up requesting a new IP address. Generally we do not offer IP changes, however considering the issue we can change the IP for you. Due to the manual work involved, this request is billable. Your VPS will be assigned a new IP address from the available pool.
Please use the following form to request IP change:
This is an automatic reply. If your request is not properly addressed, please reply in this ticket and one of our engineers will take a look.