When do you need EVPN type 5 routes?
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A type 5 route carries an IP prefix in a tenant VRF, not tied to any MAC, with the L3VNI as its label and the router MAC of the advertising leaf. I use it for external routes from a border leaf (a default route, WAN or firewall prefixes), for subnet routes so leaves without a VLAN can still reach it, for reaching silent hosts, and for routed connectivity between fabrics or sites without stretching layer 2.
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Typical uses
- Border leaf. Learns 0.0.0.0/0 from a firewall or WAN router over eBGP in the VRF (VRF-lite handoff) and re-advertises it as type 5 to every leaf.
- Subnet routes. Each leaf advertises its SVI subnets. A leaf that does not have VLAN 20 routes toward 10.10.20.0/24 using the type 5, and the receiving leaf ARPs for the host.
- Silent hosts. A host that never sends has no type 2. The type 5 gets traffic to a leaf that owns the subnet, which then resolves the host.
- Layer 3 only tenants and DCI, including summaries between sites.
Config sketch
router bgp 65001
vrf TENANT-A
address-family ipv4 unicast
advertise l2vpn evpn
redistribute direct route-map RM-TENANT-SUBNETSrouter bgp 65001
vrf TENANT-A
rd 10.0.0.11:50001
route-target import evpn 65000:50001
route-target export evpn 65000:50001
redistribute connectedType 2 and type 5 together
A /32 host route from a type 2 is more specific than the /24 type 5, so longest match sends traffic straight to the leaf where the host really is. The type 5 is the fallback.
They will ask next
Can a type 5 route carry a /32?
Yes. Loopbacks, service VIPs and host routes exported toward another site are often type 5 /32s.
Traps
- Expecting type 5 to help bridging inside a subnet. It is layer 3 only.
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