How do you implement a front end for Nway LDAP in Mirror Mode

From the documentation...
In MirrorMode two providers are set up to replicate from each other (as a multi-master configuration), but an external frontend is employed to direct all writes to only
one of the two servers. The second provider will only be used for writes if the first provider crashes, at which point the frontend will switch to directing all writes to the second provider. When a crashed provider is repaired and restarted it will automatically catch up to any changes on the running provider and resync.

My question(s)
- could someone provide guidance or a link to any system they have implemented to "direct writes to only one server" while theoretically allowing reads from either provider. We typically use the F5 in round robin but am not sure how to set it up to to differentiate between writes and reads.
- Should I just avoid the complication and just use the F5 to provide simple failover?