Multicast in VXLAN with BGP EVPN control-plane

 Hello, We are trying to run multicast in data center overlay network. In our data centers we are using L3 leaf-spine topology with VXLAN. For the control plane BGP EVPN is used.  Leaf switches are deployed in an MLAG configuration. We want to run multicast between hosts that are on same vlan across switches in different MLAG domains. Multiple multicast receivers, as well as multiple senders are connected to different MLAG domains and are all in the same VLAN. Multicast receiver can receive m-c stream from the sender if both of them are in the same MLAG domain. But if receiver is connected to...
Continue reading →

Alert for multicast routing table overflow?

I have a customer with an Arista-DCS-7150S-52-CL-R running 4.15.9M code.  They have a fairly complex set of hosts and a large number of multicast groups.  Occasionally, one host will become deaf to a group.  A “netstat -ng” on the host indicates that the operating system still thinks it is subscribed to the group. Is there any way to determine if the routing table is overflowing and multicast routes are being trimmed?  Or if other limited multicast resources are being exhausted? I suspect the solution is to reduce the number of multicast groups being used, but we would like to determine the root...
Continue reading →

MBR (Multicast Border Router)

Intro Enabling PIM MBR on an interface (where we don’t have an upstream PIM neighbor) will allow multicast traffic from remote sources that are outside of our PIM domain to be treated as locally connected sources. We typically see this scenario when we are receiving multicast feeds from a remote Exchange and a PIM neighbourship is not established on our upstream links. In the current PIM implementation (EOS 4.14.0F and later) EOS will drop multicast traffic that is not considered to be locally connected by default and we need to configure MBR to allow this multicast data. In the interfaces...
Continue reading →

show ip mfib output – “notify”

Hi, can anyone tell me what “notify” means in the following output, does it relate to MSDP? (note MSDP not running on the device): sh ip mfib g.g.g.gActivity poll time: 60 secondsg.g.g.g s.s.s.s Vlan256 (iif) Vlan152 (notify) Vlan251 Activity 0:17:20 agog.g.g.g 0.0.0.0/0 Vlan256 (iif) Vlan251  

VXLAN to VLAN trunk port – multiple multicast-groups?

Hello everybody, I have configured the following VXLAN networks using VMware vShield which should be mapped to VLANs on a virtual Arista Switch (vEOS 4.15.OF): VNI5000 / Multicast 225.1.1.1 / Map to VLAN 500 VNI5001 / Multicast 225.1.1.2 / Map to VLAN 501 VNI5002 / Multicast 225.1.1.3 / Map to VLAN 503 But on the interface vxlan 1, I can only set one multicast-group on the interface vxlan 1. Is there the possibility to set multiple multicast-group on this interface (one multicast-group per VNI)? I also cannot create more than one VXLAN interface – is this a general limitation or...
Continue reading →

Layer 3 Leaf-Spine – Rendezvous Point Placement?

Hello everybody, I have configured a leaf-spine architecture (4 leafs, 2 spines), see attached image. L3 routing is enabled on leafs and spines and eBGP is used between them. To enable VXLAN (from VMware Hosts), multicast needs to be configured. So far, ip multicast-routing and ip pim sparse-mode is set. Where do I configure the rendezvous point (RP) and which method would I use? I would prefer to place it on the spine switches using anycast-rp, but one spine switches does not reach the other spine switch (as the route to spine1 is not announced to spine2 by the leafs...
Continue reading →