I am not sure but as per my current job experience you may be asked:
1. What do you understand by Leased License and what is the purpose of leased license?
2. Types of CAL's, and how do you assign them?
3. What is the difference between Server & Publisher product of QlikTech and from where do you managed it?
4. If Server crashes then how do you check the reason behind it, or error log, where will you find that log?
5. If document is dependent on other load and if first load fails then what happens to the next document?
These few were best of my knowledge which I feel could be asked in interview since it co-relates our day to day work in server administration.
Adding to the list of Kumar's Questions.
2. Algorithms on Load Balancing (can be combined with a real time scenario - asking you to suggest the best algorithm)
3. Various Options available to configure users in the system
4. Different distribution options of a QlikView Document
5. Optimal usage of Different CAL based on a specific scenario
Just thought about few - I guess there are more to be added.