With Win2003, it was pretty easy for us to get started. We fixed the registry-based discovery to allow multiple license servers and to be applied in the admin tools too.
We also reduced network traffic a few ways:
First check the registry – if we’ve been told what LS to use, why look anywhere else?
Next try discovery via Active Directory – one LDAP query is faster than many RPCs to domain controllers.
For Domain discovery, first try local (on-site) DCs. Only if everything else fails should we try contacting off-site DCs.
Stop the discovery process as soon as we find the first LS. Don’t do any further discovery unless the LS we’ve found is no longer available.
Finally, we allowed LSs to be installed on any server, not just DCs.
Windows 2003 SP1
After Win2003 shipped we had some time to sit down and look at customer data, to try to fix the top issues that were causing customers to have to call in.
We finally made Registry Discovery a first-class citizen. Why not prompt at install time for the LS name, and populate the registry then? How about a WMI provider and a Group Policy to populate the registry too?
We also made a troubleshooting tool that ran through the whole discovery process and logged everything that happened:
Finally, we added something that should have been obvious from the start: why not check the TS to see if it’s also an LS? After all, a single-TS deployment is pretty common.
We’re waiting to see how all the changes we’ve made are received, so we haven’t made any discovery changes in Longhorn.
Of course Longhorn Server isn’t done yet. Is there anything else we’ve missed? Please let me know – either commenting here or using the Email link at the top-right corner.
So where did we go wrong? In part, our original design was incomplete. We should have realized that no automated configuration works 100% of the time. Even DNS allows manual configuration at the client!
Secondly, we should have consulted more with customers before we shipped the original design. That would have uncovered the problem with installing everything on a domain controller. Likewise, talking with the Active Directory team here at Microsoft (back when they were the sole AD experts) would have clued us in on the Site concept, and the fact that inter-Site network traffic is expensive.
What did we do right? Well, the fact that we’ve made continual improvements is a good thing.
Here are some links for more licensing information: