Layer 3 Handoff
Location in GUI: Provision
» SD-Access
» Fabric Sites
» Fabric Infrastructure
» Border Node
» Configure
» Layer 3 Handoff
Diagram
Section titled “Diagram”Classes
Section titled “Classes”border_devices (catalyst_center.fabric)
Section titled “border_devices (catalyst_center.fabric)”Name | Type | Constraint | Mandatory | Default Value |
---|---|---|---|---|
l3_handoffs | List | [l3_handoffs] | No |
l3_handoffs (catalyst_center.fabric.border_devices)
Section titled “l3_handoffs (catalyst_center.fabric.border_devices)”Name | Type | Constraint | Mandatory | Default Value |
---|---|---|---|---|
name | String | Yes | ||
interfaces | List | [interfaces] | Yes |
interfaces (catalyst_center.fabric.border_devices.l3_handoffs)
Section titled “interfaces (catalyst_center.fabric.border_devices.l3_handoffs)”Name | Type | Constraint | Mandatory | Default Value |
---|---|---|---|---|
name | String | Yes | ||
virtual_networks | List | [virtual_networks] | Yes |
virtual_networks (catalyst_center.fabric.border_devices.l3_handoffs.interfaces)
Section titled “virtual_networks (catalyst_center.fabric.border_devices.l3_handoffs.interfaces)”Name | Type | Constraint | Mandatory | Default Value |
---|---|---|---|---|
name | String | Yes | ||
local_ip_address | IP | No | ||
peer_ip_address | IP | No | ||
peer_ipv6_address | IP | No | ||
local_ipv6_address | IP | No | ||
tcp_mss_adjustment | Integer | min: 500 , max: 1440 | No | |
vlan | Integer | min: 2 , max: 4093 | Yes |
Examples
Section titled “Examples”Example-1: Basic Layer 3 Handoff with Multiple Virtual Networks
This example demonstrates how to configure a basic Layer 3 handoff on an SD-Access border device for connecting fabric virtual networks to external Layer 3 infrastructure. Layer 3 handoffs enable routing between SD-Access fabric virtual networks and external networks through IP Transit connections.
The Layer 3 handoff configuration includes:
- Border device specification (BR01) with Layer 3 and Layer 2 functionality
- IP Transit name (IP_TRANSIT) for external connectivity identification
- Physical interface assignment (TenGigabitEthernet1/1/4) for high-bandwidth connectivity
- Multiple virtual network mappings with dedicated IP addressing and VLAN segmentation
- Point-to-point IP addressing for each virtual network (local and peer IP addresses)
- VLAN tagging (120, 121, 122) for traffic segregation across virtual networks
catalyst_center: fabric: border_devices: - name: BR01 border_types: - LAYER_3 - LAYER_2 default_exit: true import_external_routes: false local_autonomous_system_number: 65001 l3_handoffs: - name: IP_TRANSIT interfaces: - name: TenGigabitEthernet1/1/4 virtual_networks: - name: SDA_VN_USERS local_ip_address: 10.0.0.1/24 peer_ip_address: 10.0.0.2/24 vlan: 120 - name: SDA_VN_PRINTERS local_ip_address: 11.0.0.1/24 peer_ip_address: 11.0.0.2/24 vlan: 121 - name: SDA_VN_CORPORATE local_ip_address: 12.0.0.1/24 peer_ip_address: 12.0.0.2/24 vlan: 122
Note
The l3_handoffs name
must match the name of the IP Transit.
Example-2: Single Virtual Network Layer 3 Handoff
This example shows how to configure a simplified Layer 3 handoff with a single virtual network for environments with basic external connectivity requirements and single-tenant scenarios including tcp-mss adjustment.
catalyst_center: fabric: border_devices: - name: BR01 border_types: - LAYER_3 default_exit: true import_external_routes: true local_autonomous_system_number: 65001 l3_handoffs: - name: CORPORATE_TRANSIT interfaces: - name: GigabitEthernet1/0/1 virtual_networks: - name: CORPORATE_VN local_ip_address: 192.168.1.1/30 peer_ip_address: 192.168.1.2/30 vlan: 100 tcp_mss_adjustment: 1400
Example-3: High-Availability Layer 3 Handoff with Redundant Interfaces
This example demonstrates how to configure Layer 3 handoffs across multiple physical interfaces for high availability and load balancing in critical network environments.
catalyst_center: fabric: border_devices: - name: BR01 border_types: - LAYER_3 - LAYER_2 default_exit: true import_external_routes: false local_autonomous_system_number: 65001 l3_handoffs: - name: PRIMARY_TRANSIT interfaces: - name: TenGigabitEthernet1/1/1 virtual_networks: - name: PRODUCTION_VN local_ip_address: 10.1.1.1/30 peer_ip_address: 10.1.1.2/30 vlan: 101 - name: TenGigabitEthernet1/1/2 virtual_networks: - name: PRODUCTION_VN local_ip_address: 10.1.2.1/30 peer_ip_address: 10.1.2.2/30 vlan: 102
Example-4: Multi-Border Layer 3 Handoff Configuration
This example shows how to configure Layer 3 handoffs across multiple border devices for distributed fabric architecture with redundant external connectivity points.
catalyst_center: fabric: border_devices: - name: BR01 border_types: - LAYER_3 - LAYER_2 default_exit: true import_external_routes: false local_autonomous_system_number: 65001 l3_handoffs: - name: NORTH_TRANSIT interfaces: - name: TenGigabitEthernet1/1/1 virtual_networks: - name: ENTERPRISE_VN local_ip_address: 172.16.1.1/30 peer_ip_address: 172.16.1.2/30 vlan: 201 - name: BR02 border_types: - LAYER_3 - LAYER_2 default_exit: false import_external_routes: false local_autonomous_system_number: 65001 l3_handoffs: - name: SOUTH_TRANSIT interfaces: - name: TenGigabitEthernet1/1/1 virtual_networks: - name: ENTERPRISE_VN local_ip_address: 172.16.2.1/30 peer_ip_address: 172.16.2.2/30 vlan: 202
Example-5: Layer 3 Handoff with External Route Import
This example demonstrates how to configure a Layer 3 handoff with external route import enabled for learning routes from external networks and propagating them throughout the SD-Access fabric.
catalyst_center: fabric: border_devices: - name: BR01 border_types: - LAYER_3 - LAYER_2 default_exit: true import_external_routes: true local_autonomous_system_number: 65001 l3_handoffs: - name: WAN_TRANSIT interfaces: - name: TenGigabitEthernet1/1/3 virtual_networks: - name: BRANCH_CONNECTIVITY_VN local_ip_address: 203.0.113.1/30 peer_ip_address: 203.0.113.2/30 vlan: 300 - name: INTERNET_ACCESS_VN local_ip_address: 198.51.100.1/30 peer_ip_address: 198.51.100.2/30 vlan: 301
Example-6: Service Provider Layer 3 Handoff Configuration
This example shows how to configure Layer 3 handoffs for service provider environments with customer-specific virtual networks and multi-tenant isolation requirements.
catalyst_center: fabric: border_devices: - name: SP_BR01 border_types: - LAYER_3 - LAYER_2 default_exit: true import_external_routes: false local_autonomous_system_number: 65100 l3_handoffs: - name: CUSTOMER_A_TRANSIT interfaces: - name: TenGigabitEthernet1/1/5 virtual_networks: - name: CUSTOMER_A_PROD_VN local_ip_address: 10.100.1.1/30 peer_ip_address: 10.100.1.2/30 vlan: 1001 - name: CUSTOMER_A_DEV_VN local_ip_address: 10.100.2.1/30 peer_ip_address: 10.100.2.2/30 vlan: 1002 - name: CUSTOMER_B_TRANSIT interfaces: - name: TenGigabitEthernet1/1/6 virtual_networks: - name: CUSTOMER_B_PROD_VN local_ip_address: 10.200.1.1/30 peer_ip_address: 10.200.1.2/30 vlan: 2001