🐛 Describe the bug

When using nodes connected by IPv6, training proceeds correctly, but emits these misleading messages at log level error:

2024-05-22 06:25:20.552227-04:00 Error From <host>: [W socket.cpp:436] [c10d] The server socket cannot be initialized on [::]:22010 (errno: 97 - Address family not supported by protocol).

There's no good way I know of to filter these out, since they come from C++, and I don't want to ignore error messages.

The logic causing this is in socket.cpp: we try all possible addresses returned by getaddrinfo, logging errors if any of them fail, but returning true if any of them succeed. I think the fix is simple: just move the error message into the failure case of tryListen(int family) instead.

Versions

2.3.1 (and earlier)

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