ZeroMQ favors one IP when DNS name resolves to two IPs

[gitzko]

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Issue description

ZeroMQ seems to favor one IP over the other when DNS name returns two IPs. Like tcp://log_svc:20000 and

nslookup log_svc
Server:         127.0.0.11
Address:        127.0.0.11#53

Non-authoritative answer:
Name:   log_svc
Address: 192.168.6.54
Name:   log_svc
Address: 192.168.6.55

Environment

• libzmq version (commit hash if unreleased): https://github.com/zeromq/libzmq/commit/ecc63d0d3b0e1a62c90b58b1ccdb5ac16cb2400a
• OS: Running in Windows Server 2022 Docker container

Minimal test code / Steps to reproduce the issue

1. send log message using m_socket->send(msg, ZMQ_DONTWAIT);

What's the actual result? (include assertion message & call stack if applicable)

The log messages arrive more often on one IP than the other

What's the expected result?

The log messages are evenly distributed between both IPs