Can I change rabbitmq node name?

The following is what should be in the /etc/rabbitmq/rabbitmq-env.conf file (create it):

NODENAME=rabbitNodeName@myServerName

Next restart RabbitMQ:

sudo service rabbitmq-server restart

I think yes, you can configure any of this parameters using environment variables, it's described on RabbitMQ configuration page https://www.rabbitmq.com/configure.html