MySQL Replication, failover to read-only and EE

Client is hosting their own sites on W2kServer with IIS. I have already discussed the EngineHosting option and they prefer to manage their own hosting. They want to use 2 servers; one to host and one to replicate. I am guessing load balance, etc. I am NOT a server admin so I am only relaying as much as I am able.

We have already developed one EE 2.0 site using XAMPP as a hosting option but we are changing that, etc. We will be building another EE 2.0 site and they would like to have a situation where they can replicate the databases across 2 servers. One of their IT team had a question I am not sure I can answer.

So what happens if we failover to the read-only copy? What functionality of the site writes information to the database? If it’s a small amount of the site that needs the write functionality this configuration may work well enough until we get the master back online. Most of the time we are talking only a few min for maintenance purposes. I think we can probably live with the few issues it may have until we either get the master back up or promote the slave to be the master. I am working with our network team to provide the hardware load balancer for the mysql servers. This will provide a way to failover to the slave database in the event the master is ever down. I still need to know what happens when it does failover to the read only copy, will the site really work well enough to get by until the master is brought back up?

Can anyone help me with this question?

Thanks …