All about Local Host Cache.

What is the refresh time for Local host cache. And what is the reset time for LHC.

LHC is refreshed every 30 minutes
you can refresh/recreate manually when IMA is stopped:
"dsmaint recreatelhc" or "dsmaint refreshlhc" -> restart IMA

And, when the citrix license server is down, how long will the existing citrix session work, with the information >from the LHC.

Licensing information is not in LHC - Grace Period fpr License Server is 30 days
It is stores in c:\program files\citrix\MPS-WSXICA_MPS-WSXICA.ini

Is it possible to view the LHC information. Where do i find it?.

File is located in c:\program files\citrix\independent management architecture\imalhc.mdb

Every citrix server has a copy of the LHC, and works as a backup, if the datastore goes down.

LHC is a subset of the IMA Datastore, yes

If the datastore goes down. Is it possible to launch the CMC, from the information in the LHC.

You can launch PSC und AMC but changes are not possible