Replaced my RAID card in my Dell R710, and imported the foreign configuration from the last RAID card, ESXi started normally but the VMs are invalid and the datastore is gone. I'm going to guess that this is because of the new RAID card. But how do i retrieve the datastore that I had my VMs on?
From vSphere you can choose to add a data store, you should be able to select Disk/LUN then select the LUN that has the datastore name listed in the "VMFS Label" column. That should tell you this was previously a Datastore. Once you hit next it should give you the option to keep the existing signature and add it back as a datastore. Here is an article I found on the topic as well for more supporting information: