The Core Flow: Multicast Setup & IGMP in ST 2110

STEP 1 — Define Overall Fabric Architecture

What you’re deciding:
• Leaf/spine topology
• Non-blocking bandwidth
• Port speeds (25/40/100/200G)

Best references:
• Cisco IP Fabric for Media Design Guide – “IP Fabric Architecture” (~pp. 6–12)
• Arista Networks ST 2110 Deployment Guide – “Leaf-Spine Architecture” (~pp. 3–6)

Key takeaway: Build a non-blocking leaf/spine fabric first—everything else depends on it.

STEP 2 — Define Addressing Plan (Unicast + Multicast)

What you’re deciding:
• Subnets per VLAN
• Multicast address ranges (239.x.x.x structure)
• Source-specific vs ASM

Key takeaway: Bad addressing = unfixable later.

STEP 3 — Configure VLANs and Underlay Routing

Key takeaway: Multicast rides on a clean, deterministic underlay.

STEP 4 — Enable IGMP Snooping (Layer 2 control)

Key takeaway: IGMP = who gets the stream.

STEP 5 — Configure IGMP Querier

Key takeaway: No querier = multicast eventually breaks.

STEP 6 — Configure PIM-SM (Layer 3 multicast routing)

Key takeaway: PIM = how multicast moves between subnets.

STEP 7 — Define Rendezvous Point (RP)

Key takeaway: RP is the control anchor for multicast trees.

STEP 8 — Configure QoS (absolutely critical)

Key takeaway: No QoS = packet loss = visible artifacts.

STEP 9 — Configure PTP (timing layer)

Key takeaway: Timing failure = total system failure.

STEP 10 — Enable Redundancy (ST 2022-7)

Key takeaway: Broadcast assumes zero packet loss tolerance.

STEP 11 — Deploy NMOS / Control Layer

Key takeaway: NMOS = what connects streams (not multicast itself).

STEP 12 — Monitoring & Telemetry

Key takeaway: You don’t “set and forget” multicast — you continuously observe it.

The Whole System in One Line:
Fabric → Addressing → Underlay → IGMP → PIM → QoS → PTP → Redundancy → NMOS → Monitoring

What You Just Built

• Network = highway
• IGMP = subscription
• PIM = routing map
• NMOS = control brain
• PTP = timing reference