Page cannot be displayed - intermittent issue

Firstly, if you're using Internet Explorer as your browser, turn off "Show friendly HTTP error messages" (internet options / advanced), so that you have a chance of seeing the actual error returned, instead of that generic error page that IE replaces it with.

If you're still getting the same generic error, then your client is probably getting a TCP RST. When the virtual is in that broken state, I suggest running "curl -vk /" from the commandline of the LTM to eliminate anything between your client and LTM from being the cause, though this might not work well if your application requires cookies or authentication in order to reproduce the issue.

Also confirm whether the problem affects multiple clients simultaneously.

You could also add some logging in irules to try and identify exactly where the failure is occurring, and enable reset packet logging (tmsh modify sys db tm.rstcause.pkt value enable), then check /var/log/ltm to see if that gives you an indication of what the problem is. Remember to disable rstcause logging again later.

You could also get a tcpdump capture of the issue occurring, and then look at it in wireshark to see if the SSL stack is sending any fatal alerts