You have multiple servers. Despite there being a sync between them, only one can be the master for certain operations. For example, only one server can hold the official invitation list. The other bouncers will have to check the master list. This master is called the FSMO.
So how do you know which server is the FSMO? How do you find the FSMO in your domain?
Here's how:
- open cmd
- type: netdom query fsmo
You can also:
- -open ACTIVE-DIRECTORY-USERS-AND-COMPUTERS.
- -right-click on the domain-name (on the left-hand side).
- -click OPERATIONS MASTER.
- -it should show you there as well. At the different tabs at the top, you can select which OPERATION you are interested in.
There are other ways as well.