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kasi suresh
kasi suresh

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When DNS Broke Our Azure App — and Everything Looked Healthy

When DNS Broke Our Azure App — and Everything Looked Healthy

This one was sneaky.
Azure App Gateway — healthy
App Service — running
AFD probes — green
Logs — clean

But users were timing out. Pages were loading slow. Something was off.

The Issue with ?
Private DNS Zone wasn’t linked to the right VNet.
Our backend API (moved behind a Private Endpoint) couldn’t resolve the FQDN.
No error — just quiet timeouts.

Fix Applied:
Linked the right Private DNS Zone to staging VNet
Cleared stale records
Restarted the App Service to reset DNS cache

Learnings:
In Azure, DNS issues don’t always throw errors — sometimes they just break user experience silently.
Always double-check:
DNS zone links
NSG + UDR routing
App-level DNS caching
Have you been bitten by DNS in the cloud? Let’s share battle scars

Azure #KasdevTech #DNSIssue #PrivateEndpoints #AzureWorld #MicrosoftCloud #AppService #DevOps #CloudNetworking #Troubleshooting

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