Luigi Iotti: > > I wonder if the machine is running something that slows down traffic > > that looks "suspicious" to a data rate of 1 byte/s. > > But the same behaviour is exhibited by two machines, connected to the > Internet by completely different carriers with different service agreements.
In the first post you mentioned that both machines are operated by you. Begin speculation: You configured both systems in a similar way. End speculation. One of my experiences with Postfix is that people cut-and-paste configurations from elsewhere, and that they do not always fully understand the consequences. I would not be surprised if there was some network rate limiting feature that you inadvertantly turned on, and that limits the data rate to 1 byte/second under some conditions. Wietse