MySQL Instance Bind IP vs Port

[Kevin Riley]

I have inherited a number of MySQL installations which are configured with bound IP addresses to allow multiple instances to exist on an individual Linux server. I would have expected to use different ports rather than IPs to achieve the same result.

Is there a benefit to using the bind-address method of installing multiple MySQL instances on a single server, and is this ever a best practice? Would the preferred method be to assign unique port numbers to each instance, and allow them all to respond to the default IP address for the server? Are there any configuration or use-case considerations that might favor the multiple IP address configuration?

Thank you for any information you can provide.