diff --git a/CHANGELOG.md b/CHANGELOG.md
index 67560868..857d504c 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [2.26.1] - 2024-08-22
+### Fixed
+- Fix boot set schema validation bug preventing valid session templates from being created
+
 ## [2.26.0] - 2024-08-20
 ### Added
 - BOS automatically tags IMS images with the 'sbps-project: true' tag when using SBPS as the rootfs provider.
diff --git a/api/openapi.yaml.in b/api/openapi.yaml.in
index 2587147d..b32c6955 100644
--- a/api/openapi.yaml.in
+++ b/api/openapi.yaml.in
@@ -497,7 +497,7 @@ components:
             A null value means the Session has not encountered an error.
           maxLength: 65536
       additionalProperties: false
-    V2BootSetData:
+    V2BootSet:
       description: |
         A Boot Set is a collection of nodes defined by an explicit list, their functional
         role, and their logical groupings. This collection of nodes is associated with one
@@ -543,13 +543,6 @@ components:
           $ref: '#/components/schemas/BootSetRootfsProviderPassthrough'
       additionalProperties: false
       required: [path, type]
-    V2BootSet:
-      allOf:
-        - $ref: '#/components/schemas/V2BootSetData'
-        - anyOf:
-          - required: [node_list]
-          - required: [node_roles_groups]
-          - required: [node_groups]
     V2SessionTemplateArray:
       description: An array of Session Templates.
       type: array
diff --git a/src/bos/server/controllers/v2/sessiontemplates.py b/src/bos/server/controllers/v2/sessiontemplates.py
index 043b5dc0..681c8c61 100644
--- a/src/bos/server/controllers/v2/sessiontemplates.py
+++ b/src/bos/server/controllers/v2/sessiontemplates.py
@@ -54,6 +54,7 @@
     "enable_cfs": True,
     "name": "name-your-template"}
 
+BOOT_SET_NODE_FIELDS = [ "node_list", "node_roles_groups", "node_groups" ]
 
 def _sanitize_xnames(st_json):
     """
@@ -79,10 +80,10 @@ def _validate_sanitize_session_template(session_template_id, template_data):
     # The boot_sets field is required.
     if "boot_sets" not in template_data:
             raise ParsingException("Missing required 'boot_sets' field")
-
-    # All keys in the boot_sets mapping must match the 'name' fields in the
-    # boot sets to which they map (if they contain a 'name' field).
+    
     for bs_name, bs in template_data["boot_sets"].items():
+        # All keys in the boot_sets mapping must match the 'name' fields in the
+        # boot sets to which they map (if they contain a 'name' field).
         if "name" not in bs:
             # Set the field here -- this allows the name to be validated
             # per the schema later
@@ -91,6 +92,11 @@ def _validate_sanitize_session_template(session_template_id, template_data):
             raise ParsingException(f"boot_sets key ({bs_name}) does not match 'name' "
                                    f"field of corresponding boot set ({bs["name"]})")
 
+        # Also, validate that each boot set has at least one of the BOOT_SET_NODE_FIELDS
+        if not any(field_name in bs for field_name in BOOT_SET_NODE_FIELDS):
+            raise ParsingException(f"Boot set {bs_name} has none of the following "
+                                   f"fields: {BOOT_SET_NODE_FIELDS}")
+
     # Convert the JSON request data into a SessionTemplate object.
     # Any exceptions raised here would be generated from the model
     # (i.e. bos.server.models.v2_session_template).
@@ -130,6 +136,7 @@ def put_v2_sessiontemplate(session_template_id):  # noqa: E501
     except Exception as err:
         LOGGER.error("Error creating session template '%s': %s", session_template_id,
                      exc_type_msg(err))
+        LOGGER.debug("Full template: %s", template_data)
         return connexion.problem(
             status=400, title="The session template could not be created.",
             detail=str(err))