1. Do you see the HTTPS web service logging anything for the requests? - Did not see this but from F5 using tcpdump i can see response coming on port 443 from both the DIPsit is health monitor traffic, isn't it? it is not tcp reset, is it?
2.The monitor status for https for the 2 DIPs shows as Inactive, Down. - Is it necessary that DIPs gateway should be F5 for monitor to work?if pool member is able to return health monitor traffic to bigip, it is fine.
3.There is no receive string configured on the monitor? - Is the receive string mandatory to be defined?it is not mandatory.
4. Can you use " openssl s_client -connect 1.1.1.1:443" - you mean execute this cmd from the F5 prompt ?yes
and for sending request, are you suggesting i use only, " GET /HeartBeat/Heartbeat.htm" and NOT the part "HTTP/1.0\r\n\r\n" ?you have to put HTTP/1.0 but \r\n\r\n is just hitting enter twice.
openssl s_client -connect 1.1.1.1:443
GET /HeartBeat/Heartbeat.htm HTTP/1.0
is the curl command supported on LTM with version 10.2.1?yes
by the way, can you also show us the https_default_mn health monitor configuration?