We have a domain controller setup which also holds our roaming profiles and home directories.... DNS/DHCP... we also have an Exchange server which is a domain controller as well, also running DNS and both machines are Global Catalogs.
My question is, basically we are trying to build a more fault tolerant system and have some sort of backup should one machine go down where people can still work. At the moment if the "primary" domain controller goes down the network seems to slow down and people have a lot of problems logging on and having unresponsive systems.
As far as I'm aware they should still be able to be authenticated by the exchange server should the domain controller go down, all clients have secondary DNS set as the exchange server so this should still be ok also. The only problem is that they will not have access to their profile directory or their home directory, would this be the sole reason why machines appear so unreponsive? Or is it to do with the other server roles as these can only be applied to one server?
Was just wondering as our domain controller has gone down a couple of times recently out of hours when it is difficult to resolve the issue and thinking of ways we can minimise downtime for the people we have who have to work out of normal hours (we have a 24 hour department)