A rally which is broad based is a healthier one and is more sustainable. One way of measuring the breadth is to check the % of stocks trading above the 200 day moving average (MA).
See the chart below:
The chart shows the % of Nifty 500 stocks trading above the 200 day MA . The number is 95%. This means 95% of stocks are bullish. While this may be a bit overheated, it shows the rally is broad based.
The rally can continue. There may be pullbacks. But there is a high probability that this trend is here to stay and can continue for few years more.