We just got back from the Naval Weapons Base in Seal Beach, CA. The access for on base RV parks is usually for Active, Retired (Military or DOD), or 100% Disabled Veterans. Typically if you do not have a military/DOD identification card it is difficult to get on base because of the security issues. A DD214 will not get you access.
We just bought our RV so we are newbies. We bought a 2016 - 36' LA Allegro Open Road Class A coach. We're at the learning stage.