Setting up Jumbo frames in OSP17.1 is missing NeutronGlobalPhysnetMtu: 9000

Issue

• Following jumbo frames config doc there was no mention of the need to set NeutronGlobalPhysnetMtu: 9000 .

• we are still unable to create external VM networks with MTU 9000 . We are getting below error.

2024-09-26 09:19:54.938 16 WARNING neutron.services.revisions.revision_plugin [req-83d02c2d-e9be-4e30-9119-21d2618615d6 8a21731f2c1a4dde989475c6d7d36129 0d39156f1f6446e5bdb10c63bf26a963 - default default] Could not find related network for resource <neutron.db.rbac_db_models.NetworkRBAC[object at 7f2547bc24c0] {project_id='0d39156f1f6446e5bdb10c63bf26a963', id='6b83dd89-9149-4fc7-831d-0ff5f8a4461a', target_tenant='*', action='access_as_shared', object_id='9b3b28ba-4a18-44cd-9339-e8b883593bee'}> to bump revision.
2024-09-26 09:19:54.973 16 INFO neutron.db.segments_db [req-83d02c2d-e9be-4e30-9119-21d2618615d6 8a21731f2c1a4dde989475c6d7d36129 0d39156f1f6446e5bdb10c63bf26a963 - default default] Added segment 968f31a2-0a10-4f4f-b815-2dede91f71e6 of type vlan for network 9b3b28ba-4a18-44cd-9339-e8b883593bee
2024-09-26 09:19:54.975 16 INFO neutron.pecan_wsgi.hooks.translation [req-83d02c2d-e9be-4e30-9119-21d2618615d6 8a21731f2c1a4dde989475c6d7d36129 0d39156f1f6446e5bdb10c63bf26a963 - default default] POST failed (client error): The server could not comply with the request since it is either malformed or otherwise incorrect.
2024-09-26 09:19:54.981 16 INFO neutron.wsgi [req-83d02c2d-e9be-4e30-9119-21d2618615d6 8a21731f2c1a4dde989475c6d7d36129 0d39156f1f6446e5bdb10c63bf26a963 - default default] 10.198.22.41,192.168.131.191 "POST /v2.0/networks HTTP/1.1" status: 400  len: 326 time: 0.3349776