diff --git a/releasenotes/notes/cell-id-db-sync-nova-manage-8504b54dd115a2e9.yaml b/releasenotes/notes/cell-id-db-sync-nova-manage-8504b54dd115a2e9.yaml
index 8c616dcc8b18..d68c5a57abfb 100644
--- a/releasenotes/notes/cell-id-db-sync-nova-manage-8504b54dd115a2e9.yaml
+++ b/releasenotes/notes/cell-id-db-sync-nova-manage-8504b54dd115a2e9.yaml
@@ -3,6 +3,7 @@ upgrade:
   - |
     'nova-manage db sync' can now sync the cell0 database.
     The cell0 db is required to store instances that cannot be scheduled to
-    any cell. Before the 'db sync' command is called a cell mapping
-    for cell0 must have been created using 'nova-manage cell_v2 map_cell0'.
+    any cell. Before the 'db sync' command is called, the cell0 database
+    must be created by the operator and a cell mapping for cell0 must be
+    created using 'nova-manage cell_v2 map_cell0'.
     This command only needs to be called when upgrading to CellsV2.
diff --git a/releasenotes/notes/cells-single-migration-command-0e98d66e31e02a50.yaml b/releasenotes/notes/cells-single-migration-command-0e98d66e31e02a50.yaml
index def0454664b1..4e9a52764be5 100644
--- a/releasenotes/notes/cells-single-migration-command-0e98d66e31e02a50.yaml
+++ b/releasenotes/notes/cells-single-migration-command-0e98d66e31e02a50.yaml
@@ -10,4 +10,9 @@ upgrade:
     The new command is
     "nova-manage cell_v2 simple_cell_setup --transport_url <transport_url>"
     where transport_url is the connection information for the current message
-    queue used by Nova.
+    queue used by Nova. Operators must create a new database for cell0 before
+    running `cell_v2 simple_cell_setup`. The simple cell setup command expects
+    the name of the cell0 database to be `<API database name>_cell0` as it will
+    create a cell mapping for cell0 based on the API database connection, sync
+    the cell0 database, and associate existing hosts and instances with the
+    single cell.
diff --git a/releasenotes/notes/ocata-requires-cellv2-96bd243be874d77f.yaml b/releasenotes/notes/ocata-requires-cellv2-96bd243be874d77f.yaml
index 189e496a6fdd..ad0f39ec33d4 100644
--- a/releasenotes/notes/ocata-requires-cellv2-96bd243be874d77f.yaml
+++ b/releasenotes/notes/ocata-requires-cellv2-96bd243be874d77f.yaml
@@ -4,4 +4,9 @@ upgrade:
     cell and host mappings in Newton. If you have not done
     this, Ocata's `db sync` command will fail. Small deployments
     will want to run `nova-manage cell_v2 simple_cell_setup`
-    on Newton before upgrading.
+    on Newton before upgrading. Operators must create a new database for cell0
+    before running `cell_v2 simple_cell_setup`. The simple cell setup command
+    expects the name of the cell0 database to be `<API database name>_cell0` as
+    it will create a cell mapping for cell0 based on the API database
+    connection, sync the cell0 database, and associate existing hosts and
+    instances with the single cell.