DDP: errno: 97 - Address family not supported by protocol

I am running distributed training; it works fine but I am getting these annoying warnings:

[W socket.cpp:426] [c10d] The server socket cannot be initialized on [::]:1234 (errno: 97 - Address family not supported by protocol).
[W socket.cpp:601] [c10d] The client socket cannot be initialized to connect to [host]:1234 (errno: 97 - Address family not supported by protocol).
[W socket.cpp:601] [c10d] The client socket cannot be initialized to connect to [::ffff:xx.xx.xx.xx]:1234 (errno: 97 - Address family not supported by protocol).
              ⋮

IPv6 is disabled on all the systems. I guess these warnings are related to IPv6. Is there any way to disable this warning?