问题
This is regarding the amazon hosting. Sometimes, the server doesn't respond with packets greater than a specific length (about 1400 characters). So any operation would work if it involve downloading/reading of packets within that length; while the requests greater than these lengths are not received by the client. Every other website works.
For example, if you are making a WinSCP connection, authentication etc. will be done but it won't be able to execute the commands as simple as "ls" or listing the directory contents because of the packet length issues.
This only happens at a few clients, sometimes and starts working when the network is restarted. The behavior is consistent across all the protocols.
来源：https://stackoverflow.com/questions/20812137/packets-of-length-1400-not-being-received-from-a-specific-server