Important Points To Remember - Dell S3048-ON Configuration Manual

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 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 secondary interface P2 is blocked for the member VLANs (M11 to Mn).
Following figure illustrated the FRRP Ring R1 topology:
Figure 32. FRRP Ring using VLTi links

Important Points to Remember

• VLTi can be configured only as the primary interface for the primary interface of any FRRP ring.
• Only RSTP and PVST are supported in the VLT environment. Enabling either RSTP or PVST effects FRRP functionality even though
these features are disabled on FRRP enabled interfaces.
• Dell Networking OS does not support coexistence of xSTP and FRRP configurations. Meaning, if there is any active FRRP ring in the
system, then you cannot enable xSTP in the system globally or at the interface level. Similarly, if xSTP is enabled, then you cannot
configure FRRP in the system.
• You cannot configure VLT LAG interfaces as FRRP ring interfaces.
• When ICL is configured as an FRRP ring interface, you cannot remove ICL and VLT domain configurations.
• When FRRP is enabled on a VLT domain, you cannot enable any flavor of the spanning tree protocol (STP) concurrently on the nodes
corresponding to that VLT domain. Meaning, FRRP and xSTP cannot coexist in a VLT environment.
282 Force10 Resilient Ring Protocol (FRRP)