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Figure 45. FRRP Ring Connecting VLT Devices
You can also configure an FRRP ring where both the VLT peers are connected to the FRRP ring and the VLTi acts as the
primary interface for the FRRP Master and transit nodes.
This active-active FRRP configuration blocks the FRRP ring on a per VLAN or VLAN group basis enabling the configuration to
spawn across different set of VLANs. The FRRP configuration where VLTi nodes act as the primary or secondary interfaces
ensure that all the optics used to connect VLT domains across data centers are fully utilized.
The primary requirement for the active-active FRRP configuration to work is that the VLTi between two VLT peers must act as
the primary interface of the Master and transit nodes of the FRRP ring.
NOTE:
As the secondary interface of the FRRP master node is blocked for member VLAN traffic, VLTi cannot act as the
secondary interface in an FRRP ring topology.
Example Scenario
Following example scenario describes an Active-Active FRRP ring topology where the ring is blocked on a per VLAN or VLAN
group basis allowing active-active FRRP ring for different set of VLANs.
In this scenario, an FRRP ring named R1 is configured with VLT Node1 acting as the Master node and VLT Node2 as the transit
node. Simillary, an FRRP ring named R2 is configured with VLT Node2 as the master node and VLT node1 as the trasit node.
In the FRRP ring R1, the primary interface for VLT Node1 is the VLTi. P1 is the secondary interface, which is an orphan port that
is participating in the FRRP ring topology. V1 is the control VLAN through which the RFHs are exchanged indicating the health
of the nodes and the FRRP ring itself. In addition to the control VLAN, multiple member VLANS are configured (for example, M1
through M10) that carry the data traffic across the FRRP rings. The secondary port P1 is tagged to the control VLAN (V1). VLTi
is implicitly tagged to the member VLANs when these VLANs are configured in the VLT peer.
As a result of the VLT Node1 configuration, the FRRP ring R1 becomes active by blocking the secondary interface P1 for the
member VLANs (M1 to M10).
VLT Node2 is the transit node. The primary interface for VLT Node2 is VLTi. P2 is the secondary interface, which is one of the
orphan port participating in the FRRP ring. V1 is the control VLAN through which the RFHs are exchanged. In addition to the
control VLAN, multiple member VLANS are configured (for example, M1 to M10) that carry the data traffic across the FRRP
rings. The secondary port P2 is tagged to the control VLAN (V1). VLTi is implicitly tagged to the member VLANs when these
VLANs are configured in the VLT peer.
As a result of the VLT Node2 configuration on R2, the primary interface VLTi and the secondary interface P1 act as forwarding
ports for the member VLANs (M1 to M10).
In the FRRP ring R2, the primary interface for VLT Node1 (transit node) is the VLTi. P1 is the secondary interface, which is
an orphan port that is participating in the FRRP ring topology. V1 is the control VLAN through which the RFHs are exchanged
indicating the health of the nodes and the FRRP ring itself. In addition to the control VLAN, multiple member VLANS are
configured (for example, M11 through Mn) that carry the data traffic across the FRRP rings. The secondary port P1 is tagged to
the control VLAN (V1). VLTi is implicitly tagged to the member VLANs when these VLANs are configured in the VLT peer.
As a result of the VLT Node1 configuration on R2, the FRRP ring R2 becomes active. The primary interface VLTi and the
secondary interface P1 act as forwarding ports for the member VLANs (M11 to Mn).
VLT Node2 is the master node. The primary interface for VLT Node2 is VLTi. P2 is the secondary interface, which is one of the
orphan port participating in the FRRP ring. V1 is the control VLAN through which the RFHs are exchanged. In addition to the
Force10 Resilient Ring Protocol (FRRP)
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