Note
This feature is introduced in VAST Cluster 5.3.1.
Overview of Layer 3 Connectivity for Virtual IP Pools
By default data connections between client devices and the VAST Cluster use Layer 2. Layer 2 (Data Link Layer) handles communication within the same network segment using MAC addresses, focusing on local data transfer between devices, such as on a switch.
Alternatively, you can enable Layer 3 for these communications. Layer 3 facilitates communication between different networks using IP addresses, It determines the best path for data across multiple networks, typically through routers. BGP (Border Gateway Protocol), a key Layer 3 protocol, is used for routing between different autonomous systems (ASes) on the internet, helping manage data paths based on network policies and availability. To use this option, switches must be L3 enabled.
Layer 2 should be used if clients connect to the cluster locally, using simple networks. Layer 3, with BGP, should be used if clients are connecting across complex networks, and customer switches support BGP.
Creating a Layer 3 BGP Configuration
Follow these steps to configure a Layer 3 BGP configuration. Only one BGP configuration can be configured for a cluster.
Navigate to the Network Access page, and select the BGP Configurations tab.
Click Create BGP.
Enter these values for the BGP configuration:
Name
The name of the configuration, as it will appear in the table.
VAST ASN
The ASN presented by CNodes to upstream routers.
External ASN
The ASN expected to be presented to CNodes by upstream routers.
Alternatively, you can leave this field blank and toggle the Any External ASN option on.
Subnet bits
The number of bits in the subnet. For IPv4, this should be 32, for IPv6, 128 (i.e., a single address in the subnet)
VIP Grace Period
The period of time after a BGP session is dropped before the virtual IPs advertised in the session link are moved to another CNode.
Click Create. The configuration appears in the list of configuration in the table.
In the Network Access page, select VIP Pools.
Right-click an existing virtual IP pool, and select Edit, or click Create Virtual IP Pool, to create a new one. If you are creating a new virtual IP pool, follow the steps in Managing Virtual IP Pools to define the pool.
In the Advanced section, toggle Enable L3 on.
In the BGP section, select the BGP Configuration from the list.
Click Create or Update.
In the Network Access page, select DNS.
Right-click the existing DNS configuration, and select Edit, or click Create DNS to create a new one. If you are creating a new DNS, follow the steps in Configuring the VAST Cluster DNS Service via VAST Web UI.
In the L3 section, toggle Enable L3 on.
Click Create or Update.
Modifying a Layer 3 BGP Configuration
Navigate to the Network Access page, and select the BGP Configurations tab.
Right-click on the BGP configuration in the list, and select Edit.
Make changes to the configuration as necessary, and click Update.
Deleting a Layer 3 BGP Configuration
Navigate to the Network Access page, and select the BGP Configurations tab.
Right-click on the BGP configuration in the list, and select Remove.
BGP Peering Connections
Once a BGP configuration is created, CNodes in the cluster are connected to the upstream customer switch as BGP peers (the customer switch must support L3 networking for this). You can see the status of these peering connections in the BGP Connections tab on the Network Access page. Each connection listed in this tab shows a CNode, the hardware port on the CNode that is has a BGP peering connection, and the state of the connection.
A valid BGP peer connection state is Established. If a peer is unreachable, state will show Down. If there is a configuration mismatch, it will show Idle.