An AR-R configuration is shown in the following example.
*A:PE-2>config>service>system>vxlan# info
----------------------------------------------
assisted-replication-ip 10.2.2.2
----------------------------------------------
*A:PE-2>config>service>vpls# info
----------------------------------------------
vxlan instance 1 vni 4000 create
assisted-replication replicator
exit
bgp
exit
bgp-evpn
evi 4000
vxlan bgp 1 vxlan-instance 1
no shutdown
exit
<snip>
no shutdown
----------------------------------------------
In this example configuration, the BGP advertises a new inclusive multicast route with tunnel-type = AR, type (T) = AR-R, and tunnel-id = originating-ip = next-hop = assisted-replication-ip (IP address 10.2.2.2 in the preceding example). In addition to the AR route, the AR-R sends a regular IR route if ingress-repl-inc-mcast-advertisement is enabled.
You should disable the ingress-repl-inc-mcast-advertisement command if the AR-R does not have any SAP or SDP bindings and is used solely for Assisted-Replication functions.
The AR-R builds a flooding list composed of ACs (SAPs and SDP bindings) and VXLAN tunnels to remote nodes in the VPLS. All objects in the flooding list are broadcast/multicast (BM) and unknown unicast (U) capable. The following example output of the show service id vxlan command shows that the VXLAN destinations in the flooding list are tagged as ‟BUM”.
*A:PE-2# show service id 4000 vxlan
===============================================================================
Vxlan Src Vtep IP: N/A
===============================================================================
VPLS VXLAN, Ingress VXLAN Network Id: 4000
Creation Origin: manual
Assisted-Replication: replicator
RestProtSrcMacAct: none
===============================================================================
VPLS VXLAN service Network Specifics
===============================================================================
Ing Net QoS Policy : none Vxlan VNI Id : 4000
Ingress FP QGrp : (none) Ing FP QGrp Inst : (none)
===============================================================================
Egress VTEP, VNI
===============================================================================
VTEP Address Egress VNI Num. MACs Mcast Oper L2
State PBR
-------------------------------------------------------------------------------
192.0.2.3 4000 0 BUM Up No
192.0.2.5 4000 0 BUM Up No
192.0.2.6 4000 0 BUM Up No
-------------------------------------------------------------------------------
Number of Egress VTEP, VNI : 3
-------------------------------------------------------------------------------
===============================================================================
When the AR-R receives a BUM packet on an AC, the AR-R forwards the packet to its flooding list (including the local ACs and remote VTEPs).
When the AR-R receives a BM packet on a VXLAN tunnel, it checks the IP DA of the underlay IP header and performs the following BM packet processing.
The AR-R function is only relevant to BM packets; it does not apply to unknown unicast packets. If the AR-R receives unknown unicast packets, it sends them to the flooding list, skipping the VXLAN tunnels.
If the destination IP matches its AR-IP, the AR-R forwards the BM packet to its flooding list (ACs and VXLAN tunnels). The AR-R performs source suppression to ensure that the traffic is not sent back to the originating Leaf.
If the destination IP matches its regular VXLAN termination IP (IR-IP), the AR-R skips all the VXLAN tunnels from the flooding list and only replicates to the local ACs. This is the default Ingress Replication (IR) behavior.