Problem:

when users open the netscaler link, it doesnt open at all, or it takes very long time to open. If opened, it wont show any applications. It says webpage not available kind of errors.

Solution:

Checked the vServers and found that one of the vserver is down. I have manaully opened the web server link and it is opening as expected. So, came to a conclusion that, the vServer that is pointing to this web server is causing the problem. When checked the vServer details, https monitor, which was configured to this vServer was down and that caused the problem.