Local internet breakout is a key feature of modern SD-WAN solutions, allowing direct access to cloud applications without hairpinning through a data centre. It improves performance, reduces latency, and keeps traffic off expensive MPLS links. But what happens when that breakout fails? If your network relies purely on a local internet path, you might be in for a nasty surprise.
The Reality of Local Breakout Failures š„šØ
Imagine this: Youāve got a VMware SD-WAN Edge (VeloCloud) deployed at a branch, happily sending cloud-bound traffic via a local internet breakout. No tunnels, no detoursājust clean, direct internet access. Then, without warning, the internet path dies. Maybe itās an ISP outage, maybe itās an upstream routing failure, or maybe itās just gremlins in the network. The result? Your cloud applications are dead in the water.
What Happens Next?
1. If Thereās an Alternative WAN Link ā”ļøš
If youāre lucky enough to have a secondary internet link, the SD-WAN Edge should fail over automatically. VMware SD-WAN continuously monitors link health, and if one path degrades or drops, traffic is steered to the next best path. This failover happens within 700ms to 1 second, keeping disruptions minimal.
However, not all applications handle failover gracefully. Some cloud services, like Microsoft 365 or Zoom, might drop sessions when the source IP changes, leading to a temporary service disruption.
2. If Local Breakout Fails Completely š«šØ
Now, hereās where things get messy. If thereās no backup ISP and local breakout fails, all direct-to-internet traffic is dead. What happens next depends on how your SD-WAN is configured:
Using Cloud Gateways? Youāre Safe. š”ļø If the SD-WAN Edge has an active tunnel to a VMware SD-WAN Gateway, the network can dynamically reroute traffic via the cloud backbone. Instead of using local breakout, traffic will now hairpin through the SD-WAN fabric before exiting to the internet. This keeps services alive but adds latency.
No Backup Path? Game Over. šµ If thereās no backup ISP and no active SD-WAN tunnels, youāre toast. Traffic will simply fail, users will complain, and IT will be scrambling for a fix.
Why Fusionās SD-WAN Solves This Problem šš
Fusion SD-WAN eliminates these pain points with a smarter, more resilient approach:
Multi-Path Load Balancing & Failover ā Fusion dynamically bonds multiple WAN links, so failover is seamless and instant, without session drops.
ISP-Agnostic Performance Monitoring ā Unlike traditional setups, Fusion actively probes upstream paths and detects failures before they cause disruptions.
Automatic Policy-Based Routing ā Instead of relying solely on local breakout, Fusion can dynamically shift traffic between direct breakout, cloud VPN, or backbone paths based on real-time conditions.
The Bottom Line: Donāt Rely on a Single Breakout ā ļøš
Local breakout is greatāuntil it isnāt. Without redundancy, a single failure can bring your cloud access to a grinding halt. SD-WAN solutions like Fusion provide intelligent failover, ensuring that your network remains resilient even when the unexpected happens. If youāre running business-critical applications, having a backup plan isnāt optionalāitās essential.
So, next time someone suggests relying purely on local breakout, ask them: What happens when it fails?
