Cirrostratus
NacreousHi
Firstly, are you pool and VS in an Up state? Do they have a green icon next to them which shows that the monitor is marking the service as available?
If they are available, are the clients actually hitting the VS? To check, go and look at the Statistics for the VS - do the numbers increment when you make a call to the site? If they don't then you need to look into why.
If the VS stats do change, go and look at the Pool stats. Again, do the numbers increment when making a client connection? Does the F5 send traffic to the pool members but doesn't receive any return traffic - the Out column stays at 0 whilst the In column goes up - this means that you have a routing issue and probably need to apply SNAT to the VS
If you can prove/disprove basic connectivity then you can start going a little deeper into resolving this