OD and replicas

We are going to be setting up an OD Master with many (>80) replicas. We have successfully done this in a test environment, however, several questions leap out at us:

1. What happens if the OD master fails? Is there any easy way to “promote” one of the replicas to be a master?

2. If not, can we have two masters?

3. If we want all users to be able to login in at all sites, then the database will be huge (>10000 users). Is there a way to copy the database to a CD then populate the new replica with the CD instead of having the entire database flow over the network? Some of these locations have VERY slow links. I was thinking we could then rsync or something with the Master.

4. What happens if the link goes down for a replica for some long period, and many changes take place to the master. I assume that when the link comes back, the changes would update the replica at that point?

5. If I have to rebuild the master, does that then mean I have to visit each site and setup the replication again? Doesn’t that mean it will have to download the entire database? Yikes!

What other surprises await us? I am sure there are others out there already doing this.

Thanks for your time.

Mike