Postdoc exploring tenure track faculty jobs against the wish of mentor I have been a postdoc for a year and half with a good number of publications. I feel it is the time for seriously exploring the TT faculty positions. However, my mentor wants me to work for a few more years in the current position. Though I have good rapport with my mentor, I dont know if it is ethical and practically possible for me to  proceed with applying without taking his reference. Advice will be appreciated.
It's your future and not that of your adviser, so I'm surprised that an adviser would say that they want you to work as a postdoc "for a few more years" -- which sounds far beyond the usual 3-year postdoc period.

My recommendation is essentially the same as for at least half of the questions on this forum: Communicate with your adviser. Have an honest talk about your future, why you desire to look for tenure track jobs, what you need from him in this regard, etc. You will very likely need your adviser's support (through letters, introductions, and in other ways), and the only way you'll get that is if you have honest conversations about what each of you want to get out of your current relationship.