Mysterious crash when website initialises

Question

We are running CF8 Enterprise over the top of cf7. Windows
and SQL server.
When we deploy a new site it will crash with a 500 error
usually complaining about he first database query in the page.
After this point the website runs fine.
If the website is inactive for a few hours the first time you
go there you will get the error again and then on refresh it will
work fine. The websites works fine on our development machine. We
have also moved one of our sites to our other cf7 machine and it
works fine on there.
The application imports quite a few function libraries then
runs the query which crashes. To debug I have tried cfdumping the
query and then aborting the application. I get the same result. If
I comment out half my function libraries the application works then
I see my dump. I have changed which function libraries are imported
but it is usually the same result too many functions and the
application crashes.
If I just run the database query on its own it runs fine.
I'm thinking of uninstalling cf 7 and 8 and reinstalling 8.
It is a little daunting as as there are 20 live sites on there at
the moment. Is it a good start or could it be something else? Any
help / ideas will be appreciated.
Andrew

Answer 1

Have you done any of the JRun updaters since you installed
CF7? If not, you might want to look at those.
In short, I'd recommend a fresh CF8 install. I've had 7 and 8
running on a cf7 install of JRun and things just weren't right.
You could also check out the JDBC drivers. A upgrade of those
might be in order as well.