Designing a Resilient BYOC Premise Edge Cluster with Local Survivability for Retail Sites

How-To-Articles
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Designing a Resilient BYOC Premise Edge Cluster with Local Survivability for Retail Sites

What This Guide Covers

  • Architecting a Genesys Cloud BYOC Premise deployment for physical retail or branch locations.
  • Implementing Edge Groups and Edge Clusters for high availability and load balancing.
  • Designing for Local Survivability, ensuring internal calling and basic IVR functionality continue during a WAN (Internet) outage.

Prerequisites, Roles & Licensing

  • Licensing: Genesys Cloud CX 1/2/3 with BYOC Premise.
  • Hardware: Genesys Cloud Edge Appliances (LD/Standard) or Virtual Edge (Hyper-V/VMware).
  • Permissions:
    • Telephony > Edge > Add/Edit
    • Telephony > Edge Group > Add/Edit

The Implementation Deep-Dive

1. The Strategy: The “Offline-First” Branch

For retail locations (like banks or large stores), a lost internet connection shouldn’t mean a total communications blackout. BYOC Premise allows the “Intelligence” to live on-site while the “Management” stays in the cloud.

The Strategy:

  1. The Cluster: Deploy at least two Edge appliances per site.
  2. The Edge Group: Group these Edges together so they share a common pool of trunks and local resources.
  3. The Workflow:
    • Normal Ops: Edges communicate with Genesys Cloud for routing and analytics.
    • WAN Outage: Edges enter Survivable Mode. Internal calls (Extension-to-Extension) and basic SIP trunks continue to function locally.

2. Implementing Edge Grouping and N+1 Redundancy

A single Edge is a single point of failure.

The Implementation:

  1. Navigate to Admin > Telephony > Edge Groups.
  2. Add both on-site Edges to a single group.
  3. Trunk Assignment: Assign your local SIP Trunks (e.g., from a local carrier or a legacy PBX) to the Edge Group, not to individual Edges.
  4. The Benefit: Genesys Cloud will load-balance calls across both Edges. If Edge-01 fails, Edge-02 immediately takes over the active trunk sessions without dropping existing calls.

3. Configuring Local Survivability and Emergency Routing

During a WAN outage, the Edge cannot reach the cloud-based Architect IVR or the global directory.

The Strategy:

  1. Survivable Number Plans: Configure a local number plan that maps extensions to local SIP stations.
  2. Local Trunks: Ensure your SIP trunks are physically connected to the local network (behind the Edge), not just via a cloud peering point.
  3. Emergency Routing: Configure the Edge to prioritize the Local Gateway for emergency calls. Even if the internet is down, the Edge can still push a call out over the local PRI or SIP trunk to the PSAP.
  4. The Trap: Architect flows. Complex flows (data dips, bots) will fail in survivable mode. Create a “Simplified Survivable Flow” that only performs basic transfers to a local Hunt Group or security extension.

4. Architecting Site-to-Site Trunking (Edge Peering)

For multi-site organizations, you can route calls between branches without touching the public PSTN.

The Implementation:

  1. Link your Edge Groups together using Inter-Edge Group Trunks.
  2. The Logic: Use the Edge Phone Trunk type.
  3. The Workflow: A user in the London branch dials a 5-digit extension for the Paris branch. The London Edge identifies the extension, routes it over the Inter-Edge Trunk (via your corporate WAN/MPLS), and the Paris Edge delivers it to the local phone.
  4. The Benefit: This saves thousands of dollars in international toll charges and provides a “Private Network” experience across your global enterprise.

Validation, Edge Cases & Troubleshooting

Edge Case 1: “Split-Brain” Condition

Failure Condition: The link between the two Edges in a cluster fails, but both Edges can still see the cloud. Both try to “claim” the active trunk, causing call drops.
Solution: Ensure you have a dedicated Inter-Edge Heartbeat cable (or a robust low-latency management VLAN) between the appliances. Use a “Quorum” model where an Edge will only go active if it can see its partner or a majority of the cluster.

Edge Case 2: WAN Latency and Media Clipping

Failure Condition: WAN latency exceeds 250ms, causing “Robot Voice” in the IVR prompts, even though the call is on a local Edge.
Solution: Set the Audio Buffet and Jitter Buffer settings on the Edge to “Adaptive High.” This adds slight delay but ensures the audio stream is reconstructed correctly under poor network conditions.

Edge Case 3: Certificate Expiry on Premise Edges

Failure Condition: The Edge stops communicating with the Cloud because its local management certificate expired.
Solution: Enable Automatic Certificate Renewal in the Edge settings. Ensure the Edge has outbound HTTPS access (port 443) to the Genesys Cloud Public API endpoints to fetch new certificates every 60-90 days.

Official References