Update admin arch to be able to access ephemeral storage and use AZone1 by default.

cloudformation_templates/edx-admin-reference-architecture.json

@@ -230,7 +230,7 @@
           "Fn::FindInMap":[
             "MapRegionsToAvailZones",
             { "Ref":"AWS::Region" },
-            "AZone0"
+            "AZone1"
           ]
         },
         "Tags":[
@@ -252,7 +252,7 @@
           "Fn::FindInMap":[
             "MapRegionsToAvailZones",
             { "Ref":"AWS::Region" },
-            "AZone0"
+            "AZone1"
           ]
         },
         "Tags":[
@@ -874,7 +874,23 @@
               ]
             ]
           }
-        }
+        },
+        "BlockDeviceMappings": [
+          {
+            "DeviceName": "/dev/sda1",
+            "Ebs":{
+              "VolumeSize": 100
+            }
+          },
+          {
+            "DeviceName": "/dev/sdb",
+            "VirtualName": "ephemeral0"
+          },
+          {
+            "DeviceName": "/dev/sdc",
+            "VirtualName": "ephemeral1"
+          }
+        ]
       }
     },
     "AdminSecurityGroup":{