The administrator can add a stretched VLAN in NDB using either static or dynamic VLANs. A stretched VLAN is a VLAN that spans across multiple Nutanix clusters, and allows the NDB-managed databases to communicate and migrate between different clusters. A static VLAN is a VLAN that is manually configured and assigned to the database server VMs and the databases by the administrator. A dynamic VLAN is a VLAN that is automatically configured and assigned to the database server VMs and the databases by the NDB instance, using the Nutanix Calm orchestration service. Both static and dynamic VLANs can be used to create a stretched VLAN in NDB, as long as they have the same VLAN ID and network configuration across the clusters.
The administrator cannot add a stretched VLAN in NDB using only VLANs that are not managed in NDB. A VLAN that is not managed in NDB is a VLAN that is configured and assigned to the database server VMs and the databases outside of the NDB instance, using the Nutanix Prism web console or other tools. A VLAN that is not managed in NDB cannot be used to create a stretched VLAN in NDB, as it is not recognized or controlled by the NDB instance.
References:
* Nutanix Database Management & Automation Training Course, Module 4: Nutanix Era Configuration, Lesson 4.1: Nutanix Era Configuration, slide 8.
* Nutanix Database Management & Automation Training Course, Module 6: Nutanix Era Disaster Recovery, Lesson 6.1: Nutanix Era Disaster Recovery, slides 6-7.