Quick Note — Recommend a Load-Balancing and Routing Solution
AZ-305 › Unit 4: Design infrastructure solutions › Design network solutions › Recommend a load-balancing and routing solution
Quick Note — Recommend a Load-Balancing and Routing Solution
A large global retailer's checkout API runs across three Azure regions. The team's first deployment uses one regional Application Gateway per region fronted by Azure Traffic Manager (DNS-based) for global routing across the three regions. A regional outage takes roughly 4 minutes for traffic to fail over — long enough for thousands of users to retry, abandon, and complain on social media. The architect replaces Traffic Manager with Azure Front Door Premium using AnyCast at the global edge: the same regional App Gateways remain behind it, but global edge routing decisions now happen at the network layer rather than via DNS TTL caching.…
Retrieval target
- Recommend a Load-Balancing and Routing Solution
- Closed-book recall
- 5 minutes
- Open the full lesson after a miss
Decision anchors
| Prompt | Compact answer |
|---|---|
Azure Load Balancer (ALB) | Layer-4 (TCP / UDP) regional load balancer. Distributes traffic across VMs / VMSS / containers in one region. Two SKUs: Basic (legacy, no SLA) and Standard (zone-redundant, 99.99% SLA). Supports public (internet-facing) and internal (private VNet-facing) variants. Fast and cheap; no L7 routing, no TLS termination — those go to App Gateway or Front Door. |
Application Gateway (App Gateway) | Layer-7 (HTTP / HTTPS) regional load balancer + WAF. URL-path-based routing, host-header routing, SSL offload, cookie-based session affinity, autoscaling (v2 SKU), zone-redundant. WAF tier adds OWASP CRS + bot protection. Pick for region-scoped web apps that need L7 routing or WAF — without the global edge of Front Door. |
Azure Front Door | Global anycast L7 at Microsoft's edge (200+ POPs). TLS termination, WAF, URL-path routing, geo-failover, edge caching, session affinity. Tiers: Standard (CDN + ingress) and Premium (adds Private Link to origin, managed rule sets, bot protection). The default for any multi-region or globally-served web app. |
Traffic Manager | A DNS-based global load balancer — it answers DNS queries with one of your endpoints' addresses according to a routing method. Doesn't sit in the data path; clients connect directly to the resolved endpoint. Supports TCP / UDP (anything DNS-resolvable, not just HTTP). Cheaper than Front Door; lacks WAF / edge caching / data-plane inspection. |
Read the answers once, then cover the right-hand column and reconstruct each one from the prompt. A useful answer names the requirement, the recommended control or service boundary, and the nearest alternative it rejects. If you can only recognize the answer after seeing it, retrieval is not yet secure.
Ninety-second explanation
Without notes, explain:
- What requirement signals this learning objective rather than a neighbouring one?
- Which two solution families are most likely to be compared?
- Which hard constraint eliminates the strongest distractor?
- What identity, network, data, or failure boundary must appear in the design?
- Which operational test would prove the recommendation works?
Then compare your explanation with the full lesson. Record the missing decision rule—not merely the missed product name—in your error log.
When to open the full lesson
Open the curriculum-linked lesson when you cannot explain a comparison, when a scenario depends on a numeric limit or SKU feature, or when the service is on a retirement path. Use current Microsoft Learn documentation for availability, limits, pricing, naming, and migration milestones; the quick note is intentionally compact.
Source and freshness
Derived from the linked AZ-305 lesson and retrieval deck, grounded in both attached course sources. Reviewed 2026-08-02. Current Microsoft documentation controls changing product contracts.