Unity doesn't have it's own database, we really do store all our stuff directly into the Exchange directory, no synchronization going on in that respect. We punch the information into the Exchange server on our box and let Exchange take care of syncing it around to the other servers in the site if necessary.
The Unity system has to cache some information from the Exchange directory into memory so we can get close to real time performance at a respectable number of ports. Exchange is a lot of things, but screaming fast real time access is isn't.
The cache writes through to Exchange right away so any change you make in the Unity SA will show up immediately in the Exchange directory (i.e. if you change the display name of a user in the SA you should see this in Exchange right away). Changes made in Exchange get picked up at the synchronization cycle time which is every 10 minutes by default but is adjustable up and down in the registry. I don't reccomend changing this, however... 10 minutes is about right. It'd be handy if we could register with Exchange to get notification when changes occur on a record we're interested in and pick them up on the fly, but unfortunately that's not possible at this point so we're stuck with the resync option. On the plus side it is very quick to pick up the deltas from the last directory sweep.
Our technicians can kick off a resync manually using a tool on the box called DOHPropTest, however this is password protected since it's a fairly dangerous utility if you don't know what you're doing with it.... and no, I'm not going to give out the password ;->
It would be kinda handy to have this option on the SA or something so in the case you make a change in Exchange you don't have to wait 10 minutes for it to be picked up. This is an outstanding feature request in the tracking system already.
Jeff Lindborg
Unity Product Architect
Active Voice Corp
jlindborg@activevoice.com
